Barrel rotation induced by vasopressin and related peptides in rats

Pharmacology Biochemistry & Behavior, Vol. 7, pp. 311-313. Copyright © 1977 by ANKHO International Inc. All rights of reproduction in any form reserved. Printed in the U.S.A.

Barrel Rotation Induced by Vasopressin and Related Peptides in Rats H. KRUSE, 1 TJ. B. VAN WIMERSMA G REI D A N U S 2 AND D. DE WIED

R u d o l f Magnus Institute f o r Pharmacology, Vondellaan 6, Utrecht The Netherlands (Received 14 February 1977) KRUSE, H., Tj. B. VAN WIMERSMA GREIDANUS AND D. DE WIED. Barrel rotation induced by vasopressin and re311-313, 1 9 7 7 . - - Intraventricular injection of arginine-8-vasopressin and its analogues vasotocin and lysine-8-vasopressin into rat brain evoked a special rotational behavior resembling somatostatin-induced barrel rotation [ 1]. Oxytocin and oxypressin were less active while vasopressin fragments had no effect. Vasopressin-induced barrel rotation was accompanied by pathological symptoms indicating a disturbance of muscle tone regulation and is considered to be a non-specific and toxic effect. This rotational behavior was not prevented by atropine, propranolol, phentolamine, methysergide or haloperidol but was reduced by chlorpromazine, probably due to the latter's muscle relaxing activity.

lated peptide in rats. PHARMAC. BIOCHEM. BEHAV. 7(4)

Barrel rotation Vasopressin Vasotocin Oxypressin Tocinamide Intracerebroventricular injection

IT HAS BEEN reported that high doses of somatostatin injected intracerebroventricularly (i.v.c.) in rats induced an unusual rotational behavior along the sagittal body axis, called barrel rotation [ 1 ]. A similar phenomenon observed after i.v.c, injection of arginine-8-vasopressin (AVP) led to investigate this effect of AVP and of some related peptides in more detail and to study the effect of several drugs on peptide induced barrel rotation.

Oxytocin

Pressinoic acid

Pressinamide

TABLE 1 STRUCTUREOF VASOPRESSINAND RELATEDPEPTIDES 1 2 34 5 6 78 9 Cys-Tyr-X-Gln-Asn-Cys-Pro-Y-GlyNH2 Peptide X

Arg-8- Vasopressin Arg-8- Vasotocin Oxypressin Oxytocin Lys-8- Vasopressin

METHOD Three hundred and eight Wistar male rats (TNO, Zeist) weighing 1 4 0 - 1 8 0 g were implanted with plastic cannulas into the right lateral ventricle using the technique described elsewhere [5]. The experiments were performed 1 - 5 days after the cannulation. Injection volumes were 5 #l/rat administered within 60 sec. The following peptides were used: AVP, lysine-8-vasopressin (LVP), desgiycinamide lysine-8-vasopressin ( D G - L V P ) , vasotocin, oxypressin, oxytocin, pressinoic acid, pressinamide, tocinamide and the C-terminal tripeptide of AVP: Pro-Arg-GlyNH, (Table 1). Peptides were dissolved in a drop of 0.01 N HC1 and further diluted with saline. Peptides were provided by Organon Oss, the Netherlands except somatostatin which was a gift from Dr. R. Guillemin, the Salk Institute, San Diego, U.S.A. The following blocking agents were used: Propranolol (Inderal®, ICI); Phentolamine (Regitine®, Ciba-Geigy); Methysergide (Deseril®, Sandoz); Atropine Sulphate (Merck); Haloperidol (Serenase®, Janssen); Chlorpromazine (Largactil®, Rhbne-Poulence). These were dissolved in saline and injected SC (0.5 ml/rat) in general 30 min before peptide administration except for phento-

Phe Ile Phe Ile Phe

Y Arg Arg Leu Leu Lys

lamine and haloperidol which were given 90 min prior to the i.v.c, administration of peptides. For statistics Fisher's Exact Probability Test was used. RESULTS The results are summarized in Table 2. Typical bouts of barrel rotation (BR) induced by vasopressin and its analogues started immediately or within a few minutes after the i.v.c, injection. Continuous barrel rolling lasted not longer than 2 min but in 5% of the cases alternated with intervals of prostration up to 20 min after the injection. Both clockwise and counterclockwise rotations occurred and the direction occasionally even changed during a bout. About 70% of BR fits were preceded by ataxia, body swaying (lateral head weaving), lying on one side with

1HOECHST AG, Frankfurt/Main (Germany). 2Send requests for reprints to: Dr. Tj. B. van Wimersma Greidanus, Rudolf Magnus Institute, Vondellaan 6, Utrecht, The Netherlands. 311

312

K R U S E , G R E I D A N U S A N D DE WIED TABLE 2 INDUCTION OF BARREL ROTATION (BR) BY VASOPRESSIN AND RELATED PEPTIDES Peptide

approximated ED~0*

BR

Death

ng ng ng ng /zg /~g

0/10 4/12+ 4/12t 6/127 5/10t 9/10

0/I0 0/12 4/127 3/127 1/10 5/10t

1.5 ng 8 ng 40 ng

0/10 5/147 5/127

0/10 1/14 2/127

200 ng 1 tzg 5 ~g

6/127 3/lOt 8/10

5/127 0/10t 6/10?

ca. 200 ng

/xg #g

0/12t 5/12t

0/12 0/12

ca. 7 ~g

5 1 5

/zg /xg

2/13t 4/llt

0/13 0/11

ca. 11/~g ca. 11 /xg

5 25

/xg p.g

3/12t 0/9

0/12

> > 5 txg

Pressinoic acid

5

/xg

0/12

0/12

> > 5/xg

Tocinamide

5

txg

0/12

0/12

> > 5/zg

Pro-Arg-Gly NH2

2.5/xg

0/10

0/10

> > 2.5/xg

0/11 4/12t 6/127 10/167 15/18+

0/11 0/12 1/12 2/167 4/18t

ca. 10 ng.

0/12

0/12

> > 5 p.g

Vasopressin (AVP)

Dose 1.5 8 40 200 1

5

Vasotocin

Oxypressin

Oxytocin

Pressinamide

LVP

DG-LVP

1

0.3 ng 1.5 ng 8 ng 40 ng 200 ng 5

p~g

ca. 200 ng

*Dose of peptide inducing barrel rotation in 50% of rats, estimated graphically. +p<0.05 (vs. saline).

spastic l i m b a b d u c t i o n , b o d y d i s t o r t i o n s a n d o p i s t h o t o n u s . These s y m p t o m s also c o u l d r e a p p e a r after t h e b o u t s of BR, followed b y a state of p r o s t r a t i o n u p to a few hours. T h e animals e i t h e r died w i t h i n 5 - 1 5 m i n of t r e a t m e n t due to lung e d e m a , or recovered c o m p l e t e l y . Rats n o t displaying BR o f t e n s h o w e d t r a n s i e n t ataxia, h e a d w a v i n g a n d sedation. O t h e r t y p e s of b e h a v i o r o b s e r v e d m o r e f r e q u e n t l y after vasopressin t h a n a f t e r saline i n j e c t i o n were drinking, g r o o m i n g a n d " n e s t b u i l d i n g " activity. AVP, v a s o t o c i n a n d the, in rats, u n n a t u r a l analogue LVP i n d u c e d B R over a wide dose range w i t h e x t r e m e l y flat dose-response curves a n d t h e r e f o r e s o m e t i m e p o o r doseresponse relationships. The t h r e s h o l d doses were in the 1 10 n a n o g r a m range.

O x y t o c i n a n d o x y p r e s s i n also h a d some BR activity b u t r e q u i r e d higher dose levels ( 1 - 5 ug), whereas in the p r e s e n t e x p e r i m e n t s an a m o u n t of 20 ug s o m a t o s t a t i n did n o t evoke a n y BR. T h e c o n s t i t u e n t s of A V P and v a s o t o c i n t e s t e d alone (pressinamide, t o c i n a m i d e , P r o - A r g - G l y N H ~ ) h a d n o c o n s i s t e n t effect ( p r e s s i n a m i d e ) or were inactive at all in i n d u c i n g BR, as was D G - L V P . T h e l a t t e r p e p t i d e even s e e m e d to have a b l o c k i n g effect, because a f t e r p r e t r e a t m e n t w i t h 5 pg D G - L V P i.v.c. LVP n o longer p r o d u c e d BR. Since in the saline t r e a t e d c o n t r o l animals n e v e r a n y B R was o b s e r v e d even a low f r e q u e n c y of p e p t i d e i n d u c e d BR in the e x p e r i m e n t a l g r o u p s was already significant ( p < 0.05), a c c o r d i n g to F i s h e r ' s e x a c t p r o b a b i l i t y test. T h e b l o c k i n g agents a t r o p i n e , p r o p r a n o l o l , p h e n t o l -

VASOPRESSIN AND BARREL ROTATION

313

a m i n e , m e t h y s e r g i d e a n d h a l o p e r i d o l were u n a b l e t o p r e v e n t L V P - i n d u c e d BR. O n l y c h l o r p r o m a z i n e r e d u c e d t h e i n c i d e n c e a n d s h o r t e n e d t h e d u r a t i o n o f B R significantly (Table 3).

TABLE 3 INFLUENCE OF SEVERAL BLOCKING AGENTS ON VASOPRESSININDUCED BARREL ROTATION IN RATS Blocking agent

Dose (mg/kg)

Incidence of barrel rotation

Saline A~ropine Propranolol Phentolamine Methysergide H aloperidol Chlorpromazine

-1 2.5 7.5 5 0.5 5

10/11 7/9 7/10 6/9 9/11 10/12 4/11"

The blocking agents were injected SC 30-90 min prior to 200 ng L V P i.v.c. (see Methods). *p<0.05 vs saline (Fisher's Exact Probability Test).

an ( a s y m m e t r i c ) increase in t o n e o f s t r e t c h muscles, as i n d i c a t e d b y a c c o m p a n y i n g o p i s t h o t o n u s a n d spastic dist o r t i o n s . This m a y be a direct effect o f vasopressin n o t m e d i a t e d b y cholinergic, n o r a d r e n e r g i c , d o p a m i n e r g i c or s e r o t o n e r g i c f u n c t i o n s since n o n e o f t h e b l o c k i n g agents a f f e c t e d v a s o p r e s s i n - i n d u c e d BR. T h e B R - i n h i b i t i n g effect o f c h l o r p r o m a z i n e is p r o b a b l y due to its muscle relaxing activity r a t h e r t h a n to a d o p a m i n e r g i c b l o c k a d e , b e c a u s e h a l o p e r i d o l , a m o r e specific d o p a m i n e r g i c b l o c k e r w i t h o u t muscle relaxing effect, did n o t r e d u c e BR. I n d u c t i o n o f increased muscle t o n e is also k n o w n f r o m p e r i p h e r a l a p p l i c a t i o n of o t h e r o l i g o p e p t i d e s , e.g., T R H [ 4 ] . H o w e v e r T R H i n j e c t e d i.v.c, in rats did n o t evoke BR, b u t i n d u c e d o t h e r t y p e s of circling b e h a v i o r and muscle rigidity [ 2 , 3 ] . Similar p a t h o l o g i c a l effects o n muscle t o n e r e g u l a t i o n as we o b s e r v e d a f t e r vasopressin, e.g., d i s t u r b a n c e s of b a l a n c e , gait a n d m o t o r c o o r d i n a t i o n or spastic rigidity o f l i m b e x t e n s o r s have also b e e n r e p o r t e d for s o m a t o s t a t i n [3] and m a y be r e s p o n s i b l e for its barrel r o t a t i o n a l e f f e c t as well. However, t h e r e are some differences b e t w e e n the characteristics o f B R i n d u c e d by vasopressin, as observed b y us, and s o m a t o s t a t i n , as r e p o r t e d by C o h n [ 1]. These differences are s u m m a r i z e d in Table 4. TABLE 4 DIFFERENCE BETWEEN VASOPRESSIN AND SOMATOSTATIN BY INDUCING BARREL ROTATION IN RATS

DISCUSSION The incidence of barrel rotation after i.v.c, injection of vasopressin and related peptides in rats seems to be a toxic effect, because it was accompanied by other toxic symptoms and frequently led to death (see Table 2). The occurrence of lung edema may indicate also an action on medullar vasomotor and respiratory centers by these peptides. The mode of action of vasopressin in inducing BR is unknown but may not be due to vasoconstriction, because LVP which has less vasoconstrictory activity than AVP was even more potent, while angiotensin II, a more powerful vasoconstrictory agent, failed to cause BR. Since neither ring nor tail-fragments of AVP were active, both constituents need to be present in the same molecule for the barrel rolling effect. In contrast, the behavioral activity of AVP, i.e., increased resistance to extinction of active avoidance behaviour, is mainly located in pressinamide, the ring of AVP [5]. Replacement of Phe by lle in the ring (vasotocin) did not alter BR activity, whereas replacement of Arg by Leu in the C-terminal part (oxypressin, oxytocin) led to a remarkable loss of potency. The phenomenon of barrel rotation itself seems to result from a special type of motor disturbance mainly caused by

Barrel rotation Threshold dose Dose-response relationship Duration of bouts Lethality Direction of rotations Inhibition by atropine

Vasopressin*

Somatostatint

5-10 ng 25 ~tg yes no (?) 1-2 min. ca. 30 min yes no right or left-handed left-handed only no yes

*present results. tAccordingto Cohn and Cohn 1975. Thus r o t a t i o n a l b e h a v i o r along t h e b o d y axis caused b y d i f f e r e n t p e p t i d e s a n d b r o u g h t a b o u t f e r e n t m o d e s o f action. It m a y finally be due t o logical p e p t i d e effects resulting in d i s t u r b a n c e of c o o r d i n a t i o n and r e g u l a t i o n of muscle t o n e .

can be by difpathomotor

ACKNOWLEDGEMENT We wish to thank Dr. Greven, Organon for supply of the peptides and Gerda Croiset for competent technical assistance.

REFERENCES 1. 2. 3.

Cohn, M. L. and M. Cohn. "Barrel rotation" induced by somatostatin in the non-lesioned rat. Brain Res. 96: 138-141, 1975. Cohn, M. L., M. Cohn and F. H. Taylor. Thyrotropin releasing factor (TRF) regulation of rotation in the non-lesioned rat. BrainRes. 96: 134-137, 1975. Havlicek, V., M. Rezek and H. Friesen. Somatostatin and thyrotropin releasing hormone: Central effect on sleep and motor system. Pharmac. Biochem. Behav. 4: 4 5 5 - 4 5 9 , 1976.

4. 5.

Kruse, H. Neurotropic effects of thyrotropin releasing hormone (TRH). Naunyn-Schmiedeberg's Arch. exp. Path. Pharmak. 282: R 51, 1974. De Wied, D. Behavioural effects of intraventricularly administered vasopressin and vasopressin fragments. Life Sci. 19: 6 8 5 - 6 9 0 , 1976.