Life Sciences Vol. 4, pp . 1877-1886, 1965 . Frinted in Great Britain.
EFFE(.RS 0?
Perganon Press Ltd.
ON RADIOIODINE IIPTARE AND
MEfAHOLISM IIi C-57 BROYN MICE" S.M . Joeaile Keyaki, Ph .D . and S .M . Clodovia Lockett, Ph .D . Departosnts of Chemistry and Biology, Notre Dane College, St . Louis, Missouri
(Eeceived 13 June 1965 ; in final form 29 July 1965) Wisemaa (1) reported that acute sad chronic ~~-; wi~tratioa of ohlorproastine (CPZ) to rats decreased the 6-hour thyroidal I131 ~uptake.
Othsra (2,3),
working with guinea pigs and rata, have observed similar inhibitory efisots of CPZ.
Oa the other hand, Reisa (4) reported an inoreaae in thyroidal iodine
uptake due to one dose of CPZ.
31noe reporta oa the anti-thyroidal activities
of CPZ and sites of it~ action are inconclusive, further experieeatal studies seen to be desirable and aeceeaary. The purpose of this iavsatigation van to determine : 1) whether or not CPZ does actually exert an inhibitory or stimulating effect on
I131
uptake and organic binding
in the thyroid; 2) whether or not CPZ exerts similar effscta as extrathyroidal organs auch sa the salivary glands, which are capable of concentrating iodine ; 3) the extent of CPZ effect oa renal clearance, as observation which would help to explain aq~ poeaible abnormalities in I131 uptake sad hormone synthesis;
4)
whether or not the effect i8 iacreaaed with chronic
"Supported in part by a Research (iront AM 04664-03 and AM WF664-0351 from National Institute of Arthritis and Metabolic Diaeasea, National Inatitutea of~Health, II .S . Public Health Service .
1877
18~8
RADIOIODIPE IIPTAIIE
Yol . 4, Ro . 19
administration of CPZ, or greatest rhea the animal is under the iarineace of the drug, observations xhich are of value in explaining mec~niA~ of drug effect . Materials and Methods C-57 bro++a Bale mice, 10 to 12 reeks of age, weighing 22 ± 2 g at the beginaing of each ezperimsnt rare used . at a temperature of 24 ± 2° C,
The eice were kept is a room maintained
fed Purina laboratory Chow, and gives tap water
ad lib . up to l2 hra previous to injections of 1131. Ia the atudiee~on the effects of a single dose of CPZ, 0.25 eg of chlnrpromasiae is 0.1 ml solution (Thorazine from Smith Klirre & F~enah) xaa iajeoted iatraperitoneally into each experimental moues, and the same volume of 0 .99 NwCl solution into each control mouse .
Thirty minutes after the drug or NaCl
injeotian, each mouse was given an intraperitoneal injection of 3 microcuriea of 1 131 as
X131
(Nudes:, Consultants, St . Louie) is 0 .1 ml of saline solution .
IIriae of the ca~ntrol a~ CPZ-treated animals rae collected during the interval bstreea I131 injection and time of sacrifice to determine the total I 131 elimiacted. To determine nay possible pereaaeat effects of chronic administration of CPZ, 0.25 mB of CPZ ras given iatraperitoneally per daily dose for 14 days to each experimental mouse ; each control mouse vas given an injection of 0.9fK NaCl solution at the same time .
All of the Art,d+i~ of this group (20 experimental
and 20 control) received the tracer dose of I1~ tion of the last dose of CPZ.
48
hra after the administra-
The 48-hr interval was chosen is order to eliei-
nate the temporary effects of the drug in these observations . Ail AT~IppÎ~ xere sacrificed, 30 minutes to 24 hours after the I131 iajec-
tion, by stherization and exsanguination .
Thyroids, salivary glands, and
urine were rapidly removed, neighed, and counted (in a well-type scintillation counter)
for percentage uptake of the I131 dose given; the blood was centri-
fuged and the radioactivity in O.1 g sample of serum vas determined .
The thy-
roids and salivary glands were pooled (thyroids or salivary glands of 3 animals
voi .
4,
x~niozoDixE
xo . i9
16?9
~~
in each flask), homogenised, and hydrolyzed with 20 or 40 eg of pancreatic is 3 ml of Krebs-Ringer buffer, pH 8.5, far 24 hrs at 3T C with ahakin8"
T1se
iodoamico acids of the thyroids and salivary glands were extracted iron the acidified hydrolyaatee with three 3-ml portions of n-butaaol saturated with The eztracta wre evaporated to dryness under vacuum at -5' C.
0.1 M HCl.
The
iodoaaino acids in each residue wre redieaolved in 0.3 ml a-butaaol; 25 doroliter sample of the solution and 10 microlitsre of the carrier solution oaataining KI, moaoiodotyroeins (MIT), düodotyrosiae (DIT), trliodothyraniae (T3), sad thyroxine (T4) were applied to Vhatsaa No . 1 ohromtography paper as the same spot . Separation of the iodoaQiao acids was accomplished by developing two diaeneional chro~atogram , using as the first solvent system the upper layer of täe nizture:
a-butanol:diaixane:2N MH40H (4 :1 :5) ; then the second solvent sya
tam: n-butaaol :acetic acid : water (78 ;5 :17) by volume . Areas as the chromatograms which caatained MIT, DIT, T3 and T4 wre located by aaanaing the chromatograms with ultraviolet light. prepared .
Rad3oautograma wre also
All areas on the chromatograms which coincided with darkened areas
on radioautograms were cut out, folded, planed in small vials, and assayed for radioactivity is a wll-type scintillation counter.
Radioactivity is each area
waa expressed ae per cent of Ilk activity on the ohromtograa. The data wre evaluated statistically by means of the "t" test . Reeulta One done (0 .25 mg) of CPZ exerted an inhibitory effect an I131 uptake by the thyroid as early ae
30
minutes after I131 injection (Table 1 and Fig. 1) .
During this same interval, the the serum was increased by CPZ.
I131
concentration in the salivary glands and is
Both the concentration of Il3l sad the volume
of urine slirinated were decreased by CPZ. By the end of 1 hr, the thyroid I131 uptake of the CPZ-treated mice was decreased 38;G, the salivary gland Zl3l was increased 25~, eerue I131 was increased 40%, and the concentration of I131 in urine roe decreased 747: (Fig . 2) .
ô
0 N
~p
No . of Mice ~d
~~
Per Cent of I1~
Ser®
Iajsoted Dose in :
bYfeot of One Dose of Chlorparomazias (CPZ) on I1~ Distribution Tige Attsr Injsotios
IIrias
2.30 t 0.30
0.1 a
1.04 ± 0.03
(Hrs)
2.38 = 0.20
Il~ 1.64 t 0 .06'
0.1 a
0.5
0.33 t 0.03
(Yhole)
8
1.16 t 0.05
(Yho1e)
Control
3.17 * 0.25
4.50 t 0.50
4.90 t 0.30
3.92 t 0.24
1.12 ± 0.04
0.80 * 0.02
1.00 = 0.04
3 .80 * 0.33
pc0.001
1.46 t 0.04
2.80 t 0.40
p " 0.05
0.5 1
p<0.05
8
1
p<0.05"
CPZ-Treated 20
p<0.001
20
p<0.00~1
Control
p<0.01
CPZ-Treated
p
5.52 ± 0.85
14 .Z0 ± 1.20
26 .26 ± 1"55
0.77 ± 0.02 p<0.05
lo.5z ± 1.10
0.85 *- 0.03
0.64 *- 0.03
3" 73 ± 0.31
4.44 ± 0.40 p<0.01
p>0.40
0.67 ± 0.03
11 .06 ± 1.12
6.91 ± 0.50 3.40 t 0:24
0.26 *- 0.02
9.89 ± 1.i0 p<0.01
p<0.001
6.60 ± 0.51
0.50 ± 0.03
5.60 ± 0.90 15.30 *- 1.30
0.85 ± 0.002
2
4
p<0.00~1
6.80 ± 0.86
5.2g ± 0.60
2
4
8 .15 ± 1.00
20.37 *- 1.42
8
8
12
8
8
12
Castrol
Control
8
CPZ-1~sated
CPZ11'rsated
8
p<0.001
Control
p<0.001
CPZ-~sated
p<0.001
p~0.001
7.01 ± 0.76
0.38 ± 0.02
p<0.001
0.22 ± 0.0~
p<0.001 16.80 ± 1.14
p<0.001
0.58 ± 0.05
0.05 ± 0.01
24
p>0.10
19.20 ± 1.23
p<0.001 12
24
0.08 ± 0.01
Control
12
p
'!leas- Standard $ror '~iftsrenoe is significant it pc0.05; not eignitiosnt it p . 0.05 or p> 0.05.
Yol . 4, No . 19
BADIOIODIPE DPTASE
1881
TIME IN HOURS AFTER Ilk INJECTION FTa. 1
Effeçt of one dose of CPZ (0.25 mg given 30 min previous to Il k injection) an I131 uptake by the thyroid and salivary glands .
1882
AADIOIODIAE DPTASE
Qol . 4, Ho . 19
C01~801. MICE CPZ-'18ENTEa MICE
~ _ (~]aads
(0 .1 g)
(0.1 g)
FI(3.' 2 Effsot of oae dDeD of CPZ (0.25 mg givea 30 mia ~r~vious to Il~ injection. iajectiaa) a~n I~3~ diatribntiam aae hour after I A 90~ decrease is urinary ezoretion of I131 was observed during the 1-hr interval. A continuous inorease is the effects oa thyroid and salivary glands was observed during the first 12-hr period (Fig . 1) .
By the end of the 24-hr
period, the thyroid I131 uptake of the'CPZ-treated mine almost reached the level found in the controls at the end of the 12-hr period .
The salivary
q Ô H
0
Ti,i Aftgir Injeotion
30 .o t o .95"
D
24.4 t o .75
25 .0 ± 0.56
27 .0 ± 0 .73
+ T4
37.0 ± 1 .16
N .B."
2z.o ± 0 .92
1
29.0 ± 1 .20
3
&ff~ot of 0ns Dogis of Chlampawaaains (CPZ) oa Il~ Dietribution in the T~roid
110. of ltioe
0.5
24 .0 * 0 .96
Perceats~ of T~roidal làdioactidty
8 0 .5
-~i
Cantroi
8
~P
cPZ-Trsat.d 20 1
p<0 .01 ""
20
7.~ t o .60
Control
41 .9 t 1.50
CPZ-Tr~atsd
4
8
p<0 .01
4 .33 ± 0 .40
control
N .B,
4
41 .6 ± 1.42
8
35 " 6 t 1.00 36 .5 ± 1.02
CPZ-~ated
31 .2 * 1.68
P < 0.02
8 .90 t 0 .95
12.75 t 1.05 12
11 .8.
39 .5 t 1 .23 41.6 * 1 .30
11 .8 . 8
11 .8 .
30 .4 * 1.50
Control
12
13 .9 ± 1 .30
8
CPZ-~sated
38" 2 ± 1 .47 24
p< 0.02
9 .1 ± 1 .00
12
P.B.
42 .4 ± 1 .65
Control
P.S.
24
,27.9 ± 1 .53 29.4 ± 1 .54 12
Mesa ± Standard Fror Differenoe ie si~ificaat if p<0.051 not ei~ifioaat (N .B .) if p " 0.05 or p>0.05.
CPZ-Treated
""
1884
RADIOIODIIiE IIPTASE
Yol . 4, No . 19
Tasi.M 3 Effect of Ose Dome
or
Chlorpromaaias (CPZ) oa Ilk
Distribation is the Thyroid and Salivary dlaads droop
1Po. of Mice
Control cPZ.zreated
8 8
Time After Iajeotion
Peroeata T~roidal Radioactivity is MIT + DIT
oi : Salivary Nadioactivity is MIT + DIT
0.5
54 .5 ±
9.1 ± 0.90
0.5
46.0
4.5 ± 0.60
1131 (~)
0.80" ± i.ao
p <0 .01
p ~0.01
Cmtroi
20
1
64.0 ± 1.50
12.3 ± 0.90
OPZ11'teated
ZO
1
54.0 ± 1.20
10.0 ± 0.70
Control OPZJh~eated
Cmtroi OPZ-Treated
8 8 8 8
p<0.01 4 4
p<0.01
77.5 ± 1.98
30.0 *- 1.10
± 1.93
16.9 t 1.00
78 .1
N.S .
p
12
70.3 ± 2.30
27.2 ± 1.50
12
72 .0 ± 2.37
11 .5 t 1.10
N.S,
p<0.001
Control
12
24
66 .1 ± 2.33
17 .0 t 1.30
CPZ-Treated
12
24
71 .8 ± 2.44
14 .0 ± 1.20
N .S .
N .S .
" Mena ± Standard Error gland i-~ uptake of the ooatrola and of the CPZ-treated mice reached a peak 2 hrs after I131 injection; however, the per cent of I131 is the salivary glands, of :he CP8-treated mioe ezoeeded that of the oontrols at the e~ of each experimsntal interval up to 24 hours . The aeram I131 level was always higher in the CPZ-treated animals than is the oontrola ; however, at the end of the 4-hr interval it was not sigaificant~ higher .
The highest concentration of I131 in urine was observed at 4 hrs is
the controls, sad at 12 hre is the CPZ-treated animals.
CPZ reduced renal
clearance . Compared to control values, CPZ inhibited organic binding of I131 only during the first hour of I131 metabolism in the thyroid (Tables 2 and 3) .
In
the salivary glands however, an inhibitory effect was present for at least 12
Pol . 4, hours.
ao . 19
RADIOIODIIiE IIPTIISE
1885
Althou~ the foraatiaa of IQT and DIT is the thyroid vas not affected
aignificant~ after the first hour of I1~ retaboliaa (Table 2), the bioefathssis of trüodoth~ro~aine (T3) cad th~rozine .(T~) ran inhibited aignifioaatl~ during the 24-hr period under iateetigatioa (Table 2) . Chronic adaiaiatratioa of CPZ for lb dais caused a alight, but aigaifioant (p ~ 0 .0~), iahibiticm of the 1-hr I~ uptake and organic binding in the th,roil .
This could be ca~neidsred a Bore persaneat or i~ireot effect of the drug,
since the GpE, given 48 hre prsdousl~, was rtabolised before the I1~ was adaiaiatered to these aa~~~~ .
The chronic treatasat had no aigaifioant effect
oa eali~ar~ gland I131 uptake or binding. Discussion Our data indicate that CPZ is addition to interfering rich the I131 trapping aeohaniaa is the thyroid also inter_"ered rich organic binding of iodine and with the coupling of DIT to fora T4.
Ths Lttsr obeer~atiaa ie in agree
cent with etudiea cads b7 other in~eetigatora (9,6,7) who reported that all ooapounds studied to date which inhibit organic binding of Iodine ass to affect the coupling of the iodinated t~roaiae aoleculea to fora tl~razins and trüodothyraniae core than atq other step in the bioe~atheais of the thyroidal horaoaea.
The {nhi bitory effect of CPE as the bioeyntheais of T3 and T4 could be
due to an inactivation of the ensyae eystea required for this syatheaisi although other aeohanieaa, such as the inhibition of the hypothalaue by CPZ oauaing a decrease in TSH secretion, and iaterfereace with iodide transport ~J be contributing factors. An iaorsaae is I~ uptake by the salirarf glands could be expected due to the iaereaeed caaceatration of I131 in the seras cad to the lower rate of 1131 excretion.
The ealitiary g].aada are extrathyroidal organs which rival the thy-
roid is their aridity for iodine (8,9) . The reduced renal clearance aright be due to a decreased gloserular filtration rate oauaed by CPZ.
The aeehaaias of this reaction is unlmora.
1886
BADIOIODIHE IIPTAgE
Yol. 4, No . 19
suasar~ Our observations indicate 'that a single 0.25 mg done, given 30 minutes previous to I1~ injection exerted the following effects in C-57 mice : 1) is thyroid, an inhibition of I131 uptake, or®aaio binding of I131 , and biosynthesis of thyroxine : by the sad of 1 hr, a 38K decrease in I1~ uptake
and a 1695 decrease in organic binding of z 131î by the end of 4 hra, a 5695 de-
crease is I131 uptake end a 38~ decrease in thyroxine synthesis ; and by the end of 24 hre, a 354é decrease is thyroxine synthesis ; 2) is salivary glands, a significant increase in I131 uptake during the 24 hr interval, and a significant decrease in organic binding of I131 during the 12-hr interval ;
3) is servo, an increase in I131 caaceatration, persisting for 24 hra ; 4) is urine, a decrease is I131 caaoentratioa and in the rate of I131 excre-
tion during the first 4 hra, followed by a marked increase . The inhibitory effects of CPZ were less pronounced in mice which were not under the influence of the drug during I131 injection, although pretreated rith CPZ. References 1.
R. VISENAN, Jr ., J. Pharmacol . Exp. Therap . l~, 269 (1962) .
2.
F. MAROCCO and s. BRF3dA, Minerve Aneet .
3.
(# . M. JA(iZEIS4, Fed . Prop . 18, ~ (1959)
4.
I.P .C . MURRAY ead E.M . !(oGIRR, in Ths T roid Olaad (Fàited by R. PITTRIYEIL4 aad V.R . TROTTER) v. 2, p. 1 . Butterworths, Vaahiagton, D.C . (1964) .
5.
3 . IINO, T. YAMADA, and M.A . (iREER, Endocrinology 68 , 582 (1961) .
6.
V.E . l~WYBERR2 aad E .B . ASTVOOD, J. Biol . Chem. 2~, 2977 (1960) .
7. 8.
J.B . RICHARDS sad 3.H. INfiHAR, Endocrinolo~ar ~, 198 (1959) " M.I . (3R033MAN, Ia Annual Review of P aiolo (Edited by V .E . HALL, R.R . SONIiQJSCHEN and A .C . GIESE v. 25, p . 173. Annual Review, Inc ., Palo alto, California (1963) .
9.
A. TAIIROG, (i .D . POTTFII2, aad I.L . CHÂIICOFF, Endocrinology ~4, 1038 (1959) "
ls,
332 (1953) "