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Mechanism of inhibition of experimental inflammation by antidepressant drugs
EUROPEAN JOURNAL OF PHARMACOLOGY 2 (1967) 229-233. NORTH-HOLLAND PUBL. COMP., AMSTERDAM
MECHANISM OF INHIBITION OF EXPERIMENTAL INFLAMMATION BY ANTIDEPRESSANT DRUGS E. ARRIGONI MARTELLI, E. T()TH, A. D. SEGRE and N. CORSICO Department of Pharmacology, Istituto Biologico Chemioterapico "ABC", Turin, Italy Accepted 3 November 1967
E. ARRIGONI MARTELLI, E. TOTH, A.D. SEGRE and N. CORSICO, Mechanisr~ of inhibition of experimental inflammation by antidepressant drugs, European J. Pharmacol. 2 (1967) 229-233. Desipramine, nortriptyline, amitriptyline and imipramine inhibit in decreasing order of potency the carrageenin-, dextran- and formalin-induced edema in rat paws. This effect is antagonized by adrenaleetomy, demedullation, pretreatment of rats with reserpine, guanethidine or inhibitors of noradrenaline biosynthesis. It is concluded that the anti-inflammatory effect of antidepressant drugs is due to the inhibition of catecholamine uptake and that it is a particular aspect of the potentiation of cateeholamine response by antidepressant drugs. Antidepressant drugs
Antiphlogistic activity
i . INTRODUCTION
A well known and p o s s i b l y the most i m p o r t a n t p h a r m a c o l o g i c a l p r o p e r t y of t r i c y c l i c a n t i d e p r e s s a n t drugs is t h e i r influence on n o r a d r e n a line mediated effects. This was f i r s t r e p o r t e d by Sigg (1959) who d e m o n s t r a t e d that the effects of injected n o r a d r e n a l i n e w e r e potentiated by i m i p r a m i n e a n d w a s then c o n f i r m e d in v a r i o u s in v i vo and in vitro t e s t s ( B o n a c c o r s i and G a r a t t i n i , 1966; B o n a c c o r s i and Hrdina, 1967; K a u m a n n , Basso and A r m a n d i a , 1995; Loew, 1964). The b i o c h e m i c a l explanation for the potentiation of c a t e c h o l a m i n e r e s p o n s e s is provided by r e s u l t s , u s i n g v a r i o u s methods which show that i m i p r a mine inhibits the uptake of exogenous and endogenous c a t e c h o l a m i n e s , p a r t i c u l a r l y n o r a d r e n a line, at the n e r v e endings (Axelrod, Whitby and Hertting, 1961; Glowinski and Axelrod, 1964; I v e r s e n , 1965). This inhibition would be expected to r e s u l t in an i n c r e a s e in the c o n c e n t r a t i o n of the c a t e c h o l a m i n e s available for the r e c e p t o r sites. E x p e r i m e n t a l evidence is also a c c u m u l a t i n g that c a t e c h o l a m i n e s , r e l e a s e d by s t i m u l i , p o s s i bly through a double vicious c i r c l e which also leads to the f o r m a t i o n of p l a s m a k i n i n s (Rocha Silva, 1964), inhibit p a r t i a l l y or c o m p l e t e l y the acute i n f l a m m a t o r y r e s p o n s e , probably by acting
Blockade of catecholamine uptake
as local a n t i - i n f l a m m a t o r y h o r m o n e s (Spector and Willoughby, 1964). It t h e r e f o r e s e e m e d of i n t e r e s t to investigate the influence of t r i c y c l i c a n t i d e p r e s s a n t drugs on some e x p e r i m e n t a l models of acute i n f l a m m a tion.
2. METHODS Sprague-Dawley female r a t s , 90-120 g, were used. I n f l a m m a t i o n of the rat paws was provoked by i n j e c t i n g into the p l a n t a r t i s s u e s through a 26 gauge needle: c a r r a g e e n i n (Genulacta C a r r a g e e nan, type LO 100, A/S KCbenhavns Pektinfabrik, Lille Skensved, Denmark), 0.1 ml, 1% solution; d e x t r a n (obtained f r o m BDH, m.w. = 170.000), 0.1 ml, 0.5% solution; or f o r m a l i n , 0.1 ml, 2% solution. The i n t e n s i t y of the edema was evaluated as p r e v i o u s l y d e s c r i b e d ( A r r i g o n i M a r t e l l i and Conti, 1964). Imipramine, desipramine, amitriptyline, nortriptyline were administered intraperitoneally dissolved in s a l i n e in a volume not exceeding 0.3 m l / 1 0 0 g, 1 hr before the injection of c a r r a geenin, d e x t r a n or f o r m a l i n . Control r a t s r e ceived s a l i n e alone. A d r e n a l e c t o m y and r e m o v a l of a d r e n a l medullae w e r e p e r f o r m e d u n d e r ether
230
A. ARRIGONI MARTELLI, E. T()TH, A. D. SEGRE and N. CORSICO
a n a e s t h e s i a by d o r s a l approach, the induction of i n f l a m m a t i o n .
72 hr before
3. RESULTS D e s i p r a m i n e (0.625-5 m g / k g i.p.), n o r t r i p tyline (0.625-10 m g / k g i.p.), a m i t r i p t y l i n e (1.2510 mg/kg) and i m i p r a m i n e (2.5-25 m g / k g i.p.) inhibit, in d e c r e a s i n g o r d e r of potency, the c a r r a g e e n i n , d e x t r a n and f o r m a l i n edema of r a t paws. Fig. 1 shows the d o s e / e f f e c t r e l a t i o n s h i p s . % Inhabitmn
7D 60
CARRAGEENIN EDEMA /
50
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40
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20
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50. 4O 30. 20 10_
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FORI~I.~ EDEMA
40. 30 20 10
Fig. 1. Effect of imipramine (e--. . .e), desiprarnine (. .), amitriptyline (x. . . . x}, nortriptyline (o . . . . o) on dextran, carrageenin and formalin edema in rat paws. Each value is the mean of the results obtained in 4 groups of 10 rats each.
The r a n g e of dose levels is quite s i m i l a r to that known to e x e r t a c l e a r a n t i d e p r e s s a n t effect ( A s kew, 1963; Sigg, 1959) and to block the r e - e n t r y of n o r a d r e n a l i n e into the s t o r a g e pools (Axelrod et al., 1961; Glowinski and Axelrod, 1964). The inhibition of local i n f l a m m a t i o n does not s e e m to be dependent upon an i r r i t a n t effect of the drugs, s i n c e t h e r e is no evidence of leakage into the p e r i t o n e a l cavity of Azovan blue injected i n t r a venou sly. In o r d e r to a s c e r t a i n the i m p o r t a n c e of the blocking of catecholamine uptake by a n t i d e p r e s sant drugs in the inhibition of the i n f l a m m a t o r y r e a c t i o n , the effects of these compounds have been evaluated in a d r e n a l e c t o m i z e d and d e m e d ullated r a t s , and in r a t s p r e t r e a t e d with r e s e r pine, guanethidine, or i n h i b i t o r s of n o r a d r e n a line b i o s y n t h e s i s . A d r e n a l e c t o m y and r e m o v a l of the a d r e n a l medullae p a r t i a l l y p r e v e n t s the a n t i - i n f l a m m a tory effect of d e s i p r a m i n e , n o r t r i p t y l i n e , a m i t r i p t y l i n e and i m i p r a m i n e (table 1). The r e s u l t s obtained in r a t s p r e t r e a t e d with r e s e r p i n e (10 m g / k g i.p,, 16 hr before drug a d m i n i s t r a t i o n ) a r e shown in table 2; they show that r e s e r p i n i z a tion c o n s i d e r a b l y r e d u c e s the effect of a n t i d e p r e s s a n t drugs. The t r e a t m e n t of r a t s with guanethidine (10 m g / k g i.p,, 24 and 6 hr before drug a d m i n i s t r a tion} c a u s e s a depletion of c a t e c h o l a m i n e s only at the a d r e n e r g i c n e u r o n e level leaving unaffected those of the a d r e n a l medullae (Chang, Costa and Brodie, 1965). Such a t r e a t m e n t a n t a g o n i z e s the inhibition of i n f l a m m a t o r y r e a c t i o n s by a n t i d e p r e s s a n t drugs (table 3). If a n t i d e p r e s s a n t drugs inhibit the i n f l a m m a tory r e s p o n s e through an i n c r e a s e d c a t e c h o l a mine activity the effect of these compounds should be r e d u c e d in a n i m a l s p r e t r e a t e d with i n h i b i t o r s of n o r a d r e n a l i n e b i o s y n t h e s i s . Support for this hypothesis is provided by drugs such as o l - m e t h y l - p - t y r o s i n e , an inhibitor of t y r o s i n e h y d r o x y l a s e (Specter, S j o e r d s m a and Udenfriend, 1965), and d i e t h y l d i t h i o c a r b a m a t e (DDTC), an inhibitor of d o p a m i n e - ~ - o x i d a s e (Collins, 1965) which a r e able to reduce in n o r m a l r a t s , and to inhibit a l m o s t completely in r e s e r p i n i z e d r a t s , the effect of d e s i p r a m i n e and n o r t r i p t y l i n e (fig. 2). The effects of phenylbutazone and c h l o r p r o m a z i n e a r e not affected by a d r e n a l e c t o m y or by p r e t r e a t m e n t of r a t s with r e s e r p i n e , or r e s e r pine plus d i e t h y l d i t h i o c a r b a m a t e (DDTC). The a n t i h i s t a m i n e s behave in a different m a n n e r : the inhibitory effect of c h l o r p h e n i r a m i n e is reduced by these p r e t r e a t m e n t s w h e r e a s the effect of m e p y r a m i n e is unchanged (fig. 3).
231
A N T I P H L O G I S T I C A C T I V I T Y OF A N T I D E P R E S S A N T DRUGS Table 1 E f f e c t of a d r e n a l e c t o m y and d e m e d u l l a t i o n on the a n t i p h l o g i s t i c a c t i v i t y of a n t i d e p r e s s a n t d r u g s * Treatment dose mg/kgi.p.
Carrageenin A ~ D $
Imipramine 10 Imipramine 25 Desipramine 1.25 Desipramine 5.0 A m i t r i p t y l i n e 2.5 A m i t r i p t y l i n e 10 N o r t r i p t y l i n e 1.25 N o r t r i p t y l i n e 5.0
41.5 47.2 30.9 32.8 35.2 36.8 32.5 35.2
± 5.2 ± 3.9 • 4.1 =L 3.6 ± 3.2 ± 5.3 ± 4.1 ± 3.2
39.5 42.6 26.6 21.7 29.5 32.8 26.4 29.9
Dextran A $ D $
± 4.2 =~ 5.3 ± 3.9 ±3.8 ± 5.4 ~: 4.8 • 6.9 ± 5.8
49.2 43.6 32.5 31.7 33.9 38.5 34.2 35.9
± ± ± • ± ± ± ±
3.6 3.1 4.8 5.3 3.1 4.5 3.8 4.4
Formalin A $ D :~
38.2 ± 5.2 35.3 ± 3.8 25.6 • 2.4 2 3 . 7 ± 3.9 27.2 ± 3.4 29.5 ± 3.8 25.1 ± 8.1 24.8 =L 3.9
36.1 35.2 27.3 28.5 30.1 31.4 28.5 30.6
~= 3.9 ± 4.2 ± 3.6 ±4.3 ± 3.5 :e 4.3 =e 3.8 ± 4.4
35.2 ± 3.9 32.4 =e 4.8 23.2 ~- 3.2 24.3±4.7 27.1 ± 3.9 28.3 ± 4.3 25.2 ~: 4.7 26.3 ± 3.1
* The f i g u r e s r e p r e s e n t t h e % r e d u c t i o n of e d e m a i n h i b i t i o n in " p r e t r e a t e d " r a t s c o m p a r e d w i t h n o r m a l a n i m a l s . E a c h v a l u e i s t h e m e a n :L S.E. of the r e s u l t s o b t a i n e d in 4 g r o u p s of 10 r a t s e a c h . $ A = a d r e n a l e c t o m i z e d 72 h r b e f o r e d r u g s a d m i n i s t r a t i o n ; D = d e m e d u l l a t e d 72 h r b e f o r e d r u g s a d m i n i s t r a t i o n . Table 2 E f f e c t of r e s e r p i n e on the a n t i p h l o g i s t i c e f f e c t of a n t i depressant drugs * Treatment d o s e m g / k g i.p. Imipramine 10 Imipramine 25 Desipramine 1.25 Desipramine 5.0 A m i t r i p t y l i n e 2.5 A m i t r i p t y l i n e 10 N o r t r i p t y l i n e 1.25 N o r t r i p t y l i n e 5.0
Carrageenin 71.6 63.8 65.0 60.3 59.3 58.2 62.3 64.8
Table 3 E f f e c t of g u a n e t h i d i n e on t he a n t i p h l o g i s ~ i c a c t i v i t y of antidepressant drugs * Treatment d o s e m g / k g i.p.
Dextran
=e 7.2 ± 6.8 ± 6.9 = 6.5 ± 7.3 ± 6.8 ± 7.1 =~ 6.1
65.3 63.0 60.5 62.7 63.2 67.4 57.8 54.1
± 2.4 ± 5.3 ± 6.2 ± 7.0 ± 4.3 ± 6.8 ± 8.1 =e 9.2
Imipramine 10 Imipramine 25 Desipramine 1.25 Desipramine 5.0 A m i t r i p t y l i n e 2.5 A m i t r i p t y l i n e 10 N o r t r i p t y l i n e 1.25 N o r t r i p t y l i n e 5.0
* See t a b l e 1.
* See t a b l e 1.
R e s e r p i n e , 10 m g / k g i.p., w a s g i v e n 16 h r b e f o r e d r u g s .
Guanethidine, fore drugs.
~,inhibition
NORTRIPTYLINE
2,5 mg/kg i.p. 0 20 40 O0
2.5 mg/kg i.p.
Reserpine
Reser~ne
*
DDTC
Reser~ne
÷
~-M-p-tyrosine
80
0
20
40
I "C"
± 7.2 ± 6.8 ± 6.9 =e 6.5 • 7.3 J= 6.8 ± 7.1 ± 6.1
65.3 63.0 60.5 62.7 63.2 67.4 57.8 54.1
± 2.4 ± 5.3 ± 6.2 • 7.0 • 4.3 =~ 6.8 ± 8.1 ± 9.2
80
I
ira.. I
II-
I"
•
II"
c~-M-p-tyrosine ~ -
60
l
m
DDTC
71.6 63.8 65.0 60.3 59.3 58.2 62.3 64.8
Dextran
10 m g / k g i.p. w a s g i v e n 24 a n d 6 h r b e -
DESIPRAHINE
Normal
Carrageenin
I U*=
P
I
L I
F i g . 2. E f f e c t of p r e t r e a t m e n t w i t h r e s e r p i n e , DDTC, a - M - p - t y r o s i n e , r e s e r p i n e + DDTC, o r r e s e r p i n e + a - M - p t y r o s i n e on a n t i p h l o g i s t i e a c t i v i t y of d e s i p r a m i n e and n o r t r i p t y l i n e ( c a r r a g e e n i n e d e m a } . E a c h v a l u e i s t h e m e a n of the r e s u l t o b t a i n e d in 4 g r o u p s of 10 r a t s e a c h . R e s e r p i n e - 10 m g / k g i.p. - w a s g i v e n 16 h r b e f o r e d r u g s , o t - m e t h y l p - t y r o s i n e ( a - M - p - t y r o s i n e ) - 80 m g / k g i.p. - and d f e t h y l d i t h i o c a r b a m a t e (DDTC) - 300 m g / k g i.p. - w e r e g i v e n 2 hr before drugs.
232
A. ARRIGONI MARTELLI, E. TOTH, A. D. SEGRE and N. CORSICO
Phenylbutazone Ctt~promazine ChlorpheniramineHepyramine 60rng/kg i.p. lOrng/kg i.p. 15mg/kg i.p. 15rag/l( 9 i.p. Inhibition
0 20406080
0 20406080
0 20406080
mE-
~ -
I,=,
Ad,-ena,ectom.iBN- ml-
B
II=-
Reserpine
B
Normal
020406080
Im
Reserpine
÷ INDDTC Fig. 3. Effect of phenylbutazone, chlorpromazJne, chlorpheniramine and mepyramine on carrageenin edema in normal and adrenalectomized rats and in rats pretreated with reserpine or reserpine + DDTC. Each value is the mean of the results obtained in 4 groups of 10 rats each. !
4. DISCUSSION
The r e s u l t s support the hypothesis that the inhibition of catecholamine uptake by a n t i d e p r e s s a n t drugs, making a v a i l a b l e m o r e c a t e c h o l a m i n e s at the r e c e p t o r s i t e s , i n i t i a t e s a n u m b e r of r e a c t i o n s which u l t i m a t e l y lead to an inhibition of the i n f l a m m a t o r y r e s p o n s e . This might t h e r e f o r e be c o n s i d e r e d as a p a r t i c u l a r a s p e c t of the potentiation of c a t e c h o l a m i n e r e sponse by a n t i d e p r e s s a n t drugs. I n d i r e c t support for such an explanation is obtained f r o m the r e s u l t s o b s e r v e d when the c a t e c h o l a m i n e s t o r e s have been depleted a n d / o r n o r a d r e n a l i n e b i o s y n t h e s i s has been inhibited. The p r e t r e a t m e n t of r a t s with r e s e r p i n e (10 m g / k g i.p. 16 hr before the experiment) or guanethidine (10 m g / k g i.p., 24 and 6 hr before the e x p e r i m e n t ) r e d u c e s the i n t e n s i t y of c a r r a g e e n i n - or d e x t r a n - i n d u c e d paw edema by about 20 or 30~o r e s p e c t i v e l y . Such a r e d u c t i o n s e e m s r e l a t i v e l y u n i m p o r t a n t in evaluating the a n t i - i n f l a m m a t o r y effect of a n t i d e p r e s s a n t drugs in r e s e r p i n e - or guanethidine pretreated animals. The actual degree of potentiation will u l t i mately depend upon the r e l a t i v e efficacy of the v a r i o u s compounds as i n h i b i t o r s of uptake and the blockade of r e c e p t o r s . This would explain the difference between a n t i d e p r e s s a n t drugs and phenothiazines: both groups of drugs a r e i n h i b i t o r s of uptake but only phenothiazines a r e a d r e n olytic agents at low doses (Thoenen, H u r l i m a n n and H~fely, 1964). Since i m i p r a m i n e and r e l a t e d compounds cause a marked inhibition of h i s t a m i n e (Theobald, B~ich and Kunz, 1965) it may be suggested that this property is r e s p o n s i b l e for the effect observed. However, in this instance it would be
difficult to explain the s h a r p r e d u c t i o n of the a c tivity of a n t i d e p r e s s a n t drugs in a d r e n a l e c t o mized or d e m e d u l l a t e d r a t s and in r a t s p r e t r e a t e d with guanethidine, r e s e r p i n e and i n h i b i t o r s of n o r a d r e n a l i n e b i o s y n t h e s i s . F u r t h e r m o r e r e c e n t findings of Gbzsy (GSzsy, Kat6 and S t . - J e a n , 1967) d e m o n s t r a t e that i m i p r a m i n e and d e s i p r a m i n e do not antagonize the i n c r e a s e d v a s c u l a r p e r m e a b i l i t y induced by h i s t a m i n e but enhance the a n t a g o n i s t i c effect of exogenous n o r a d r e n a l i n e . The r e s u l t s obtained in r e s e r p i n i z e d r a t s with c h l o r p h e n i r a m i n e and m e p y r a m i n e s u p p o r t the view that the inhibition of the i n f l a m m a t o r y r e action is mediated through c a t e c h o l a m i n e s . It has been shown that c h l o r p h e n i r a m i n e but not m e p y r a m i n e is able to potentiate c a t e c h o l a m i n e induced p h a r m a c o l o g i c a l r e s p o n s e s (Innes, 1958) probably by inhibiting the c a t e c h o l a m i n e uptake (Isac and Goth, 1965). The r e s u l t s with a n t i h i s t a m i n e s may t h e r e f o r e be used to support the h y pothesis which p r o p o s e s the i n t e r a c t i o n with c a t e c h o l a m i n e s as an explanation for the a n t i p h l o gistic a c t i v i t y of a n t i d e p r e s s a n t drugs. However, the p o s s i b i l i t y cannot be excluded that the sedative action of a n t i d e p r e s s a n t d r u g s may contribute, at l e a s t in part, to t h e i r a n t i phlogistic effect since the i r r i t a n t - i n d u c e d paw swelling is r e d u c e d in sedated a n i m a l s . REFERENCES Arrigoni Martelli, E. and I. Conti, 1964, Ricerche su un nuovo metodo di infiammazione sperimentale: l'edema subplantare da earragenina, 11 Farmaeo ed. prat. 19, 134. Askew, B.M., 1963, A simple screening procedure for imipramine-like antidepressant agents, Life Sci. 10, 725.
ANTIPHLOGISTIC ACTIVITY OF ANTIDEPRESSANT DRUGS Axelrod, J . , L.G. Whitby and G. Hertting, 1961, Effect of psychotropie drugs on the uptake of H - n o r e p i nephrine by t i s s u e s , Science 133, 383. Bonaccorsi, A. and S. Garattini, 1966, Effect of DMI on directly or indirectly elicited cateeholamine p r e s s o r r e s p o n s e in pithed r a t s , J. Pharm. P h a r maeol. 13, 993. Bonaccorsi, A. and P. Hrdina, 1967, Interaction between d e s i p r a m i n e and sympathomimetic agents on the c a r d i o v a s c u l a r s y s t e m , Proc. Ist Int. Symp. on a n t i d e p r e s s a n t drugs (North Holland Publ. Comp., Amsterdam) 149. Chang, C.C., E. Costa and B. B.Brodie, 1965, I n t e r a c tion of guanethidine with adrenergic neurones, J. Pharmaeol. Exp. Ther. 147, 303. Collins, G. G. S., 1965, Inhibition of dopamine f~-oxidase by diethyl-dithiocarbamate, J. Pharm. Pharmacol. 17, 526. Glowinski, J. and J . A x e l r o d , 1964, Inhibition of uptake of tritiated noradrenaline in the intact rat brain by imipramine and related compounds, Nature 204, 1318. GSzsy, B., L.Katb and A. St.-Jean, 1967, Effect of i m i pramine on the norepinephrine and h i s t a m i n e - i n duced capillary r e s p o n s e in the rat, Experientia 23, 211. Innes, I.R., 1958, Sensitization of the h e a r t and nictitating m e m b r a n e of the cat to sympathomimetic amines by antihistamine drugs, Brit. J. Pharmacol. 13, 6. Isac, L. and A. Goth, 1965, Interaction of antihista-
233
m i n i c s with norepinephrine uptake: a cocaine-like effect, L q e Sci. 4, 1898. Iversen, L . L . , 1965, Inhibition of noradrenaline uptake by drugs, J. P h a r m . Pharmacol. 17, 62. Kaumann, A., N. Basso and P. Armandia, 1965, The c a r d i o v a s c u l a r effect of N-~(methylamino-propylaminodibenzyl) HCL (DMI) and guanethidine, J. Pharmacol. Exp. Ther. 147, 54. Loew, D., 1964, Untersuchungen tiber die aminopotenzierenden Wirkungen yon a n t i d e p r e s s i v wirkenden Stoffen am Kaninehen, Med. Exp. 11, 333. Rocha Silva, M., 1964, Chemical m e d i a t o r s of the acute inflammatory reaction, Ann. N.Y. Ac. Sci. 116, 899. Sigg, E. B., 1959, Pharmacological studies with Tofra~ nil, Canad. Psyehiat. A s s . 4, 75. Spector, S., A. Sjoerdsma and S. Udenfriend, 1965, Blockade of endogenous norepinephrine synthesis by Ot-methyl-tyrosine, an inhibitor of t y r o s i n e hydroxylase, J. P h a r m . Exp. Ther. 147, 86. Spector, W.S. and D.A. Willoughby, 1964, Vasoactive amines in acute inflammation, Ann. N.Y. Ac. Sci. 116, 839. Theobald, W., O. Btich and H.A. Kunz, 1965, V e r g l e i chende Untersuchungen fiber die Beeinflussing vegetativer Funktionen durch P s y c h o p h a r m a e a in akuten T i e r v e r s u e h , A r z n e i m . - F o r s c h . 15, 117. Thoenen, H., A. Hurlimann and W. Hiifely, 1964, On the mode of action of c h l o r p r o m a z i n e on p e r i p h e r a l a d r e n e r g i c m e c h a n i s m s , Int. J. Neuropharmacol. 4, 79.
MECHANISM OF INHIBITION OF EXPERIMENTAL INFLAMMATION BY ANTIDEPRESSANT DRUGS E. ARRIGONI MARTELLI, E. T()TH, A. D. SEGRE and N. CORSICO Department of Pharmacology, Istituto Biologico Chemioterapico "ABC", Turin, Italy Accepted 3 November 1967
E. ARRIGONI MARTELLI, E. TOTH, A.D. SEGRE and N. CORSICO, Mechanisr~ of inhibition of experimental inflammation by antidepressant drugs, European J. Pharmacol. 2 (1967) 229-233. Desipramine, nortriptyline, amitriptyline and imipramine inhibit in decreasing order of potency the carrageenin-, dextran- and formalin-induced edema in rat paws. This effect is antagonized by adrenaleetomy, demedullation, pretreatment of rats with reserpine, guanethidine or inhibitors of noradrenaline biosynthesis. It is concluded that the anti-inflammatory effect of antidepressant drugs is due to the inhibition of catecholamine uptake and that it is a particular aspect of the potentiation of cateeholamine response by antidepressant drugs. Antidepressant drugs
Antiphlogistic activity
i . INTRODUCTION
A well known and p o s s i b l y the most i m p o r t a n t p h a r m a c o l o g i c a l p r o p e r t y of t r i c y c l i c a n t i d e p r e s s a n t drugs is t h e i r influence on n o r a d r e n a line mediated effects. This was f i r s t r e p o r t e d by Sigg (1959) who d e m o n s t r a t e d that the effects of injected n o r a d r e n a l i n e w e r e potentiated by i m i p r a m i n e a n d w a s then c o n f i r m e d in v a r i o u s in v i vo and in vitro t e s t s ( B o n a c c o r s i and G a r a t t i n i , 1966; B o n a c c o r s i and Hrdina, 1967; K a u m a n n , Basso and A r m a n d i a , 1995; Loew, 1964). The b i o c h e m i c a l explanation for the potentiation of c a t e c h o l a m i n e r e s p o n s e s is provided by r e s u l t s , u s i n g v a r i o u s methods which show that i m i p r a mine inhibits the uptake of exogenous and endogenous c a t e c h o l a m i n e s , p a r t i c u l a r l y n o r a d r e n a line, at the n e r v e endings (Axelrod, Whitby and Hertting, 1961; Glowinski and Axelrod, 1964; I v e r s e n , 1965). This inhibition would be expected to r e s u l t in an i n c r e a s e in the c o n c e n t r a t i o n of the c a t e c h o l a m i n e s available for the r e c e p t o r sites. E x p e r i m e n t a l evidence is also a c c u m u l a t i n g that c a t e c h o l a m i n e s , r e l e a s e d by s t i m u l i , p o s s i bly through a double vicious c i r c l e which also leads to the f o r m a t i o n of p l a s m a k i n i n s (Rocha Silva, 1964), inhibit p a r t i a l l y or c o m p l e t e l y the acute i n f l a m m a t o r y r e s p o n s e , probably by acting
Blockade of catecholamine uptake
as local a n t i - i n f l a m m a t o r y h o r m o n e s (Spector and Willoughby, 1964). It t h e r e f o r e s e e m e d of i n t e r e s t to investigate the influence of t r i c y c l i c a n t i d e p r e s s a n t drugs on some e x p e r i m e n t a l models of acute i n f l a m m a tion.
2. METHODS Sprague-Dawley female r a t s , 90-120 g, were used. I n f l a m m a t i o n of the rat paws was provoked by i n j e c t i n g into the p l a n t a r t i s s u e s through a 26 gauge needle: c a r r a g e e n i n (Genulacta C a r r a g e e nan, type LO 100, A/S KCbenhavns Pektinfabrik, Lille Skensved, Denmark), 0.1 ml, 1% solution; d e x t r a n (obtained f r o m BDH, m.w. = 170.000), 0.1 ml, 0.5% solution; or f o r m a l i n , 0.1 ml, 2% solution. The i n t e n s i t y of the edema was evaluated as p r e v i o u s l y d e s c r i b e d ( A r r i g o n i M a r t e l l i and Conti, 1964). Imipramine, desipramine, amitriptyline, nortriptyline were administered intraperitoneally dissolved in s a l i n e in a volume not exceeding 0.3 m l / 1 0 0 g, 1 hr before the injection of c a r r a geenin, d e x t r a n or f o r m a l i n . Control r a t s r e ceived s a l i n e alone. A d r e n a l e c t o m y and r e m o v a l of a d r e n a l medullae w e r e p e r f o r m e d u n d e r ether
230
A. ARRIGONI MARTELLI, E. T()TH, A. D. SEGRE and N. CORSICO
a n a e s t h e s i a by d o r s a l approach, the induction of i n f l a m m a t i o n .
72 hr before
3. RESULTS D e s i p r a m i n e (0.625-5 m g / k g i.p.), n o r t r i p tyline (0.625-10 m g / k g i.p.), a m i t r i p t y l i n e (1.2510 mg/kg) and i m i p r a m i n e (2.5-25 m g / k g i.p.) inhibit, in d e c r e a s i n g o r d e r of potency, the c a r r a g e e n i n , d e x t r a n and f o r m a l i n edema of r a t paws. Fig. 1 shows the d o s e / e f f e c t r e l a t i o n s h i p s . % Inhabitmn
7D 60
CARRAGEENIN EDEMA /
50
/,/'/
/
40
o,,
i/
,,'./,
/
./
/(
30
",,: /
20
/.
10
o~
2 ,mg/Kg i.p. 2:s Eo lo.b 2~0
~
% Inilbition 70 DEXTRAN ~EMA I 80
//" / ¢
.//'/ /"
//:/./
50. 4O 30. 20 10_
0~ 70 60 50
~
~5 ~0 lo:o 2,~" ~ ' ~
FORI~I.~ EDEMA
40. 30 20 10
Fig. 1. Effect of imipramine (e--. . .e), desiprarnine (. .), amitriptyline (x. . . . x}, nortriptyline (o . . . . o) on dextran, carrageenin and formalin edema in rat paws. Each value is the mean of the results obtained in 4 groups of 10 rats each.
The r a n g e of dose levels is quite s i m i l a r to that known to e x e r t a c l e a r a n t i d e p r e s s a n t effect ( A s kew, 1963; Sigg, 1959) and to block the r e - e n t r y of n o r a d r e n a l i n e into the s t o r a g e pools (Axelrod et al., 1961; Glowinski and Axelrod, 1964). The inhibition of local i n f l a m m a t i o n does not s e e m to be dependent upon an i r r i t a n t effect of the drugs, s i n c e t h e r e is no evidence of leakage into the p e r i t o n e a l cavity of Azovan blue injected i n t r a venou sly. In o r d e r to a s c e r t a i n the i m p o r t a n c e of the blocking of catecholamine uptake by a n t i d e p r e s sant drugs in the inhibition of the i n f l a m m a t o r y r e a c t i o n , the effects of these compounds have been evaluated in a d r e n a l e c t o m i z e d and d e m e d ullated r a t s , and in r a t s p r e t r e a t e d with r e s e r pine, guanethidine, or i n h i b i t o r s of n o r a d r e n a line b i o s y n t h e s i s . A d r e n a l e c t o m y and r e m o v a l of the a d r e n a l medullae p a r t i a l l y p r e v e n t s the a n t i - i n f l a m m a tory effect of d e s i p r a m i n e , n o r t r i p t y l i n e , a m i t r i p t y l i n e and i m i p r a m i n e (table 1). The r e s u l t s obtained in r a t s p r e t r e a t e d with r e s e r p i n e (10 m g / k g i.p,, 16 hr before drug a d m i n i s t r a t i o n ) a r e shown in table 2; they show that r e s e r p i n i z a tion c o n s i d e r a b l y r e d u c e s the effect of a n t i d e p r e s s a n t drugs. The t r e a t m e n t of r a t s with guanethidine (10 m g / k g i.p,, 24 and 6 hr before drug a d m i n i s t r a tion} c a u s e s a depletion of c a t e c h o l a m i n e s only at the a d r e n e r g i c n e u r o n e level leaving unaffected those of the a d r e n a l medullae (Chang, Costa and Brodie, 1965). Such a t r e a t m e n t a n t a g o n i z e s the inhibition of i n f l a m m a t o r y r e a c t i o n s by a n t i d e p r e s s a n t drugs (table 3). If a n t i d e p r e s s a n t drugs inhibit the i n f l a m m a tory r e s p o n s e through an i n c r e a s e d c a t e c h o l a mine activity the effect of these compounds should be r e d u c e d in a n i m a l s p r e t r e a t e d with i n h i b i t o r s of n o r a d r e n a l i n e b i o s y n t h e s i s . Support for this hypothesis is provided by drugs such as o l - m e t h y l - p - t y r o s i n e , an inhibitor of t y r o s i n e h y d r o x y l a s e (Specter, S j o e r d s m a and Udenfriend, 1965), and d i e t h y l d i t h i o c a r b a m a t e (DDTC), an inhibitor of d o p a m i n e - ~ - o x i d a s e (Collins, 1965) which a r e able to reduce in n o r m a l r a t s , and to inhibit a l m o s t completely in r e s e r p i n i z e d r a t s , the effect of d e s i p r a m i n e and n o r t r i p t y l i n e (fig. 2). The effects of phenylbutazone and c h l o r p r o m a z i n e a r e not affected by a d r e n a l e c t o m y or by p r e t r e a t m e n t of r a t s with r e s e r p i n e , or r e s e r pine plus d i e t h y l d i t h i o c a r b a m a t e (DDTC). The a n t i h i s t a m i n e s behave in a different m a n n e r : the inhibitory effect of c h l o r p h e n i r a m i n e is reduced by these p r e t r e a t m e n t s w h e r e a s the effect of m e p y r a m i n e is unchanged (fig. 3).
231
A N T I P H L O G I S T I C A C T I V I T Y OF A N T I D E P R E S S A N T DRUGS Table 1 E f f e c t of a d r e n a l e c t o m y and d e m e d u l l a t i o n on the a n t i p h l o g i s t i c a c t i v i t y of a n t i d e p r e s s a n t d r u g s * Treatment dose mg/kgi.p.
Carrageenin A ~ D $
Imipramine 10 Imipramine 25 Desipramine 1.25 Desipramine 5.0 A m i t r i p t y l i n e 2.5 A m i t r i p t y l i n e 10 N o r t r i p t y l i n e 1.25 N o r t r i p t y l i n e 5.0
41.5 47.2 30.9 32.8 35.2 36.8 32.5 35.2
± 5.2 ± 3.9 • 4.1 =L 3.6 ± 3.2 ± 5.3 ± 4.1 ± 3.2
39.5 42.6 26.6 21.7 29.5 32.8 26.4 29.9
Dextran A $ D $
± 4.2 =~ 5.3 ± 3.9 ±3.8 ± 5.4 ~: 4.8 • 6.9 ± 5.8
49.2 43.6 32.5 31.7 33.9 38.5 34.2 35.9
± ± ± • ± ± ± ±
3.6 3.1 4.8 5.3 3.1 4.5 3.8 4.4
Formalin A $ D :~
38.2 ± 5.2 35.3 ± 3.8 25.6 • 2.4 2 3 . 7 ± 3.9 27.2 ± 3.4 29.5 ± 3.8 25.1 ± 8.1 24.8 =L 3.9
36.1 35.2 27.3 28.5 30.1 31.4 28.5 30.6
~= 3.9 ± 4.2 ± 3.6 ±4.3 ± 3.5 :e 4.3 =e 3.8 ± 4.4
35.2 ± 3.9 32.4 =e 4.8 23.2 ~- 3.2 24.3±4.7 27.1 ± 3.9 28.3 ± 4.3 25.2 ~: 4.7 26.3 ± 3.1
* The f i g u r e s r e p r e s e n t t h e % r e d u c t i o n of e d e m a i n h i b i t i o n in " p r e t r e a t e d " r a t s c o m p a r e d w i t h n o r m a l a n i m a l s . E a c h v a l u e i s t h e m e a n :L S.E. of the r e s u l t s o b t a i n e d in 4 g r o u p s of 10 r a t s e a c h . $ A = a d r e n a l e c t o m i z e d 72 h r b e f o r e d r u g s a d m i n i s t r a t i o n ; D = d e m e d u l l a t e d 72 h r b e f o r e d r u g s a d m i n i s t r a t i o n . Table 2 E f f e c t of r e s e r p i n e on the a n t i p h l o g i s t i c e f f e c t of a n t i depressant drugs * Treatment d o s e m g / k g i.p. Imipramine 10 Imipramine 25 Desipramine 1.25 Desipramine 5.0 A m i t r i p t y l i n e 2.5 A m i t r i p t y l i n e 10 N o r t r i p t y l i n e 1.25 N o r t r i p t y l i n e 5.0
Carrageenin 71.6 63.8 65.0 60.3 59.3 58.2 62.3 64.8
Table 3 E f f e c t of g u a n e t h i d i n e on t he a n t i p h l o g i s ~ i c a c t i v i t y of antidepressant drugs * Treatment d o s e m g / k g i.p.
Dextran
=e 7.2 ± 6.8 ± 6.9 = 6.5 ± 7.3 ± 6.8 ± 7.1 =~ 6.1
65.3 63.0 60.5 62.7 63.2 67.4 57.8 54.1
± 2.4 ± 5.3 ± 6.2 ± 7.0 ± 4.3 ± 6.8 ± 8.1 =e 9.2
Imipramine 10 Imipramine 25 Desipramine 1.25 Desipramine 5.0 A m i t r i p t y l i n e 2.5 A m i t r i p t y l i n e 10 N o r t r i p t y l i n e 1.25 N o r t r i p t y l i n e 5.0
* See t a b l e 1.
* See t a b l e 1.
R e s e r p i n e , 10 m g / k g i.p., w a s g i v e n 16 h r b e f o r e d r u g s .
Guanethidine, fore drugs.
~,inhibition
NORTRIPTYLINE
2,5 mg/kg i.p. 0 20 40 O0
2.5 mg/kg i.p.
Reserpine
Reser~ne
*
DDTC
Reser~ne
÷
~-M-p-tyrosine
80
0
20
40
I "C"
± 7.2 ± 6.8 ± 6.9 =e 6.5 • 7.3 J= 6.8 ± 7.1 ± 6.1
65.3 63.0 60.5 62.7 63.2 67.4 57.8 54.1
± 2.4 ± 5.3 ± 6.2 • 7.0 • 4.3 =~ 6.8 ± 8.1 ± 9.2
80
I
ira.. I
II-
I"
•
II"
c~-M-p-tyrosine ~ -
60
l
m
DDTC
71.6 63.8 65.0 60.3 59.3 58.2 62.3 64.8
Dextran
10 m g / k g i.p. w a s g i v e n 24 a n d 6 h r b e -
DESIPRAHINE
Normal
Carrageenin
I U*=
P
I
L I
F i g . 2. E f f e c t of p r e t r e a t m e n t w i t h r e s e r p i n e , DDTC, a - M - p - t y r o s i n e , r e s e r p i n e + DDTC, o r r e s e r p i n e + a - M - p t y r o s i n e on a n t i p h l o g i s t i e a c t i v i t y of d e s i p r a m i n e and n o r t r i p t y l i n e ( c a r r a g e e n i n e d e m a } . E a c h v a l u e i s t h e m e a n of the r e s u l t o b t a i n e d in 4 g r o u p s of 10 r a t s e a c h . R e s e r p i n e - 10 m g / k g i.p. - w a s g i v e n 16 h r b e f o r e d r u g s , o t - m e t h y l p - t y r o s i n e ( a - M - p - t y r o s i n e ) - 80 m g / k g i.p. - and d f e t h y l d i t h i o c a r b a m a t e (DDTC) - 300 m g / k g i.p. - w e r e g i v e n 2 hr before drugs.
232
A. ARRIGONI MARTELLI, E. TOTH, A. D. SEGRE and N. CORSICO
Phenylbutazone Ctt~promazine ChlorpheniramineHepyramine 60rng/kg i.p. lOrng/kg i.p. 15mg/kg i.p. 15rag/l( 9 i.p. Inhibition
0 20406080
0 20406080
0 20406080
mE-
~ -
I,=,
Ad,-ena,ectom.iBN- ml-
B
II=-
Reserpine
B
Normal
020406080
Im
Reserpine
÷ INDDTC Fig. 3. Effect of phenylbutazone, chlorpromazJne, chlorpheniramine and mepyramine on carrageenin edema in normal and adrenalectomized rats and in rats pretreated with reserpine or reserpine + DDTC. Each value is the mean of the results obtained in 4 groups of 10 rats each. !
4. DISCUSSION
The r e s u l t s support the hypothesis that the inhibition of catecholamine uptake by a n t i d e p r e s s a n t drugs, making a v a i l a b l e m o r e c a t e c h o l a m i n e s at the r e c e p t o r s i t e s , i n i t i a t e s a n u m b e r of r e a c t i o n s which u l t i m a t e l y lead to an inhibition of the i n f l a m m a t o r y r e s p o n s e . This might t h e r e f o r e be c o n s i d e r e d as a p a r t i c u l a r a s p e c t of the potentiation of c a t e c h o l a m i n e r e sponse by a n t i d e p r e s s a n t drugs. I n d i r e c t support for such an explanation is obtained f r o m the r e s u l t s o b s e r v e d when the c a t e c h o l a m i n e s t o r e s have been depleted a n d / o r n o r a d r e n a l i n e b i o s y n t h e s i s has been inhibited. The p r e t r e a t m e n t of r a t s with r e s e r p i n e (10 m g / k g i.p. 16 hr before the experiment) or guanethidine (10 m g / k g i.p., 24 and 6 hr before the e x p e r i m e n t ) r e d u c e s the i n t e n s i t y of c a r r a g e e n i n - or d e x t r a n - i n d u c e d paw edema by about 20 or 30~o r e s p e c t i v e l y . Such a r e d u c t i o n s e e m s r e l a t i v e l y u n i m p o r t a n t in evaluating the a n t i - i n f l a m m a t o r y effect of a n t i d e p r e s s a n t drugs in r e s e r p i n e - or guanethidine pretreated animals. The actual degree of potentiation will u l t i mately depend upon the r e l a t i v e efficacy of the v a r i o u s compounds as i n h i b i t o r s of uptake and the blockade of r e c e p t o r s . This would explain the difference between a n t i d e p r e s s a n t drugs and phenothiazines: both groups of drugs a r e i n h i b i t o r s of uptake but only phenothiazines a r e a d r e n olytic agents at low doses (Thoenen, H u r l i m a n n and H~fely, 1964). Since i m i p r a m i n e and r e l a t e d compounds cause a marked inhibition of h i s t a m i n e (Theobald, B~ich and Kunz, 1965) it may be suggested that this property is r e s p o n s i b l e for the effect observed. However, in this instance it would be
difficult to explain the s h a r p r e d u c t i o n of the a c tivity of a n t i d e p r e s s a n t drugs in a d r e n a l e c t o mized or d e m e d u l l a t e d r a t s and in r a t s p r e t r e a t e d with guanethidine, r e s e r p i n e and i n h i b i t o r s of n o r a d r e n a l i n e b i o s y n t h e s i s . F u r t h e r m o r e r e c e n t findings of Gbzsy (GSzsy, Kat6 and S t . - J e a n , 1967) d e m o n s t r a t e that i m i p r a m i n e and d e s i p r a m i n e do not antagonize the i n c r e a s e d v a s c u l a r p e r m e a b i l i t y induced by h i s t a m i n e but enhance the a n t a g o n i s t i c effect of exogenous n o r a d r e n a l i n e . The r e s u l t s obtained in r e s e r p i n i z e d r a t s with c h l o r p h e n i r a m i n e and m e p y r a m i n e s u p p o r t the view that the inhibition of the i n f l a m m a t o r y r e action is mediated through c a t e c h o l a m i n e s . It has been shown that c h l o r p h e n i r a m i n e but not m e p y r a m i n e is able to potentiate c a t e c h o l a m i n e induced p h a r m a c o l o g i c a l r e s p o n s e s (Innes, 1958) probably by inhibiting the c a t e c h o l a m i n e uptake (Isac and Goth, 1965). The r e s u l t s with a n t i h i s t a m i n e s may t h e r e f o r e be used to support the h y pothesis which p r o p o s e s the i n t e r a c t i o n with c a t e c h o l a m i n e s as an explanation for the a n t i p h l o gistic a c t i v i t y of a n t i d e p r e s s a n t drugs. However, the p o s s i b i l i t y cannot be excluded that the sedative action of a n t i d e p r e s s a n t d r u g s may contribute, at l e a s t in part, to t h e i r a n t i phlogistic effect since the i r r i t a n t - i n d u c e d paw swelling is r e d u c e d in sedated a n i m a l s . REFERENCES Arrigoni Martelli, E. and I. Conti, 1964, Ricerche su un nuovo metodo di infiammazione sperimentale: l'edema subplantare da earragenina, 11 Farmaeo ed. prat. 19, 134. Askew, B.M., 1963, A simple screening procedure for imipramine-like antidepressant agents, Life Sci. 10, 725.
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