Prog. Nemo-Paychophamnacol. Pergamon Press Ltd, 1980.
Vol. Printed
4,
SUBSTITUTED Jacques
pp. 341-.340. Great Britain.
in
-s
AND ANOREXIA
DUHAULT, Laszlo Institut
BEREGI
and
Francois
ROMAN
de Recherches Servier Suresnes, France
(Final
form,
July
1980)
Abstract 1. A considerable number of modifications to the phenethylamine useful pharmacological tools for studying regulation of food studies show that anorectic drugs constitute a heterogeneous in animals by different mechanisms.
structure have provided intake. The results of these group, reducing food intake
2. A review of evidence illustrates that pharmacologically induced changes in the activity of monoamine systems are associated with pronounced reduction in food intake. While catecholamines may be involved in the anorectic activity of stimulating agents such asamphetamina the integrity of the serotoninergic system appears to be important for the reduction of food intake induced by the fenfluramine group. 3. The anorectic effect of mazindol seems to depend on both the noradrenergic systems. However, biochemical information suggests an interaction between and the nigroneostriatal DA pathways.
and dopaminergic the central 5-HT
4. Structural modifications in the lateral chain need CF group for anorectic activity, while phenoxy substituted amphetamines have no effect on foad intake, in spite of mild stimulant properties. Kev words
:
anorectic
drugs,
brain
monoamines,
brain
Abbreviations : 5,6DHT : 5,6-dihydroxytryptamine; 5-HT: 5-hydroxytryptamine; 5HTP: 5-hydoxytryptophan; amphetamine.
synaptoscmes,
serotonin
: 5-hydroxy-indola intraperitoneal;
5-HIAA IP:
neurotoxins.
acetic acid PCA: paracloro-
Introduction It is well known that the central monoamines play a role in the control Of ingestive be havior and there is evidence that anorectic drugs may decrease food intake by interacting with brain monoamines, at least in experimental animals.Furthermore biogenic amines appear to be differentially involved in the anorectic activity of these drugs. The purpose of this paper is to surenarize on food intake and biogenic amines in rats. Materials Experimental
the effect
of several
anorectic
drugs
(Fig.
1)
and Methods
conditions
The anorectic response was measured in rats. Groups of 5 adult Long Evans rats were traimd to eat their food between 09.00 till 16.00 each day and the amount eaten after 2 and 7 h were recorded. Water was available at all times.
341
342
J.
Duhault
et
al.
OH
cH2-
Cy-CH3 NH2 MAZINDOL
AMPHETAMINE
c"2 -
"1" -cH3 NH-C2H5
FENFLURAMINE
QUIPAZINE
oO“Y0
H2-CH-CH3 I NH2
0
cF3
LILLY
NOR-FLUTIOREX
110-140
cF3 H-CH2-NH-CH2 I OCH3 MK 212
SKF
1 - 39728
0 -0
A
@O&CH2-C;-CH3 NH2 LB1
Fig.
1.
Chemical
S 7342
80
structures
of
some
anorectic
drugs.
Anorectic
drugs
and
All drugs were injected intraperitoneally. before food presentation. Pretreatment (saline of the feeding period. Inhibition of feeding expressed as percent of food consumed during with food intake of rats injected with saline, Experimental In vitro according (Belin et
brain
343
monoamines
Anorectic drugs were always administered 30 min or others) was given 60 min before the start in the 2 h following food presentation was the same time the preceding day and compared tested simultaneously.
technique synaptosomal to Gray and al., 1976).
uptake Whittaker
: brain (1962).
synaptosomes Incubations
In vivo synaptosomal uptake : synaptosomes Ten days before sacrifice, some rats were dihydroxytryptamine creatine-sulphate (5,6 stereotaxic apparatus under light Nembutal controls.
were were
isolated pretreated DHT) in anesthesia.
prepared performed
from the mesencephalon as previously described
from drug treated rats were used. by one injection of 75Pg of 5,6 20 ~1 into the lateral ventricle using Sham operated animals were used as
a
In another set of experiments co trol group and 5,6 DHT pretreated rats received one intraperitoneal injection (I.P.) of 1I4Cf fenfluramine (5 PCi) and unlabelled fenfluramine (25mg/kg) in saline. Animals were killed 2 hours later, and the hypothalamus and mesencephalon were removed and dissolved in Soluene 350. The radioactivity was measured with a Packard spectrometer.
Results
and
Discussion
Table 1 shows the reduction in food intake induced by anorectic drugs and serotoninergic reagentsin saline pretreated rats. Clomipramine administered 30 min before tested drugs, significantly abolished the food suppressant effect of fenfluramine only. The 5-hydroxytryptamine precursor (5 HT), 5-hydroxytryptophan (5-HTP), potentiated the anorectic effects of amphetamine and Lilly 110-140. Pretreatment with dibenamine, an a-adrenoceptor blocker, slightly antagonized the effect of amphetamine, fenfluramine and nor-flutiorex. Pimozide, a dopamine receptor blocking agent, markedly antagonized the anorectic potency of d-amphetamine, mazindol and nor-flutiorex, thus significantly increasing the ED 50 values, whereas fenfluramine activity was not significantly altered. The new compound MK 212 and fenfluramine exhibited anorectic response to MK 212 was not affected by prior other pharmacological tools, Paraphenoxy derivatives to reduce food consumption in rats.
Anorectic activity pharmacological
(ED agents.
: mg/kg
50
i.p.)
of
Table
1
drugs
in
Clomipramine
keh;gtamine
1.34
> 25 0.27
Mazindol Quipazine ;e;$U;ramine
2.11
Lilly 110-140 Nor-flutiorex MK 212 SKF l-39728 A :ach value :D 50 values
is
the were
1.95 > 25 4.57 1.02 2.31 6.95 mean of calculated
6 determinations. according
similar anorectic administration of amphetamine
rats
30 min
5OH-Tryptophane
after
activity but clomipramine and fenfluramine
the
of
treatment
Dibenamine
or failed
with
several
Pimozide
1.08
0.97
2.27
4.32
0.20 2.05 > 10
0.30 1.15 1.72
0121
1.21
2.40
2.25
1.12 2.10
0.95 1.86
1.38
1.72
2.42
1.97
c
1.80
to
Litchfield
and
Wilcoxon
344
J.
et al.
Duhault
Table Influence by carotid
of
anorectic section 2,5
drugs h after
on midbrain 5-HT drug administration.
Name
7342 LB1 80 MK 212 SKF l-39728
*
p <
of
5-HIAA
10 20 20 20 :i
in
CONC;;;,"AiICI;
Dose mg/kg i.p.
Saline Fenfluramine Nor-flutiorex
Groups
and
I
Drugs
2 rats.
IN
5 HT
All
animals
BRAIN
(wet
were
tissue)
5 HIAA
0.48 + 0.003 0 32.2 0.02
0.72 + 0.03 0 58.2 0 03
0'3o*f 0:50 f 0.47 + 0.43 +
0'41*+ 0:79 + 0.85 + 0.75 + 0.65 +
0.51
sacrificed
0 02 0:01 0.01 0.03
+ 0.02
0'05 0:07 0.06 0.07 0.03
5 animals
0.01
As shown in Table 2, fenfluramine and nor-flutiorex, of brainserotoninand brain 5-hydroxy-indolacetic with no anorectic activity failed to modify brain The relative potency of fenfluramine tosomes is shown in Table 3. Fenfluramine respectively) but less potent than Lilly Drugs effects in vivo situations of in vitro There was a significant sacrificed 4 hours after tion (Table 4).
and
acid 5-HT
unlike in the content.
MK 212, decreased rat. The phenoxy
MK 212 as inhibitors of and MK 212 were equiactive 110-140 or clomipramine.
on the uptake of different neurotransmitters high affinity uptake (initial extracel ular inhibition of the in vitro uptake of t 14~1 fenfluramine, Lilly 110-140, or amphetamine
5-HT uptake (Ki : 1.6
the levels derivatives
in brain 10-6 and
synap10-6 M
were also stiddicd in concentration below I PM). 5-HT when rats were intraperitoneal injec-
The binding of l4 C fenfluramine (in terms of radioactivity) was determined in two specific areas of the rat brain, 2 hours after i.p. injection of 5pCi of labelled compound in 25 mg/lg fenfluramine. Table 5 shows that radioactivity was higher in mesencephalon than in hypothalamus. However, pretreatment with S,6 DHT decreased the binding of radioactivity to the hypothalamus (30 %) more than the binding to mesencephalon (15 %). Since fenfluramineelicited anorexia was decreased by destroying nerve terminals with 5,6 DHT, it could be suspected that the uptake mechanism is required at the level of neuronal membranes. In fact, in such pretreated animals, Table 6 shows a significant decrease of[I4C] 5 HT (50 %) and of [14C] fenfluramine (20 %) uptake by synaptosomes, as compared with controls. In conclusion, our findings are compatible With the existence of a serotoninergic system regulation food intake in rats. However there is evidence to implicate other central monoamines in ingestive behavior. Catecholamines play an important role in the decrease in food intake induced by amphetamine, phentermine and diethylpropion, whereas like amphetamine, mazindol appears to reduce food intake through a mechanism also involving brain dopamine as their anorectic activity is antagonized by pimozide (Table 1). Mazindol and amphetamine inhibit DA and noradrenaline uptake by mesencephalon or striatum synaptosomal preparations (Table 4) and provoke dopamine release (Table 7). MK 212 did not significantly affect DA uptake and release by synaptosomes.
Anorectic
Relative
potency
of
fenfluramine
drugs
and
and
brain
Table
3
as
inhibitor
MK 212
monoamines
of
5 HT uptake Relative
IC 50
Drugs
Fenfluramine
2.2
10-6M
2.5
10-6M
Lilly
of
4 determinations.
potency
x 10-3
of
anorectic
drugs
on
neurotransmitter
0.5
Drugs were Numbers in mg/protein/min. * pco,o5
injected brackets
25 10 mg/kg 5 mg/kg
IP IP IP
1 mg/kg
IP
4 h before represent
of
P4C]
uptake
- 5 HT dM
in
vivo,
by
14C
1
+ +
1* 1*
95
f
1
as
brain
65
(groups expressed
of
synaptosomes.
- DOPAMINE 1-M
100 + (0.021) 85 + 97 + 60 t
2*
75 88
the Sacrifice control values
fenfluramine
2 500
-
100 + (0.023) 14 +
100
4
Table Binding
400
11
4 10-8M
i4C
Fenfluramine Lilly 110-140
454
9 10-8M
Table
Effects
synaptosomes.
mg/k 110-140
Clomipramine Mean
brain
1 IC 50
MK 212
by
f
14C
1wM
3
2 2 2* 3*
4 rats). in nM of
- NOREPINEPHRINE
transported
100 +
4
(0.027) 92+
2
60:
6*
62 f
4*
compound
5
percent
Of controls.
, Groupes Control 5,6 Values in brackets 5,6 DHT (8 rats) control (8 rats) Both
groups
received
represent : 7511 g in : 511 Ci
DHT PJ 20111,
Mesencephalon
Hypothalamus
fenfluramine intraventricular intraventricular fenfluramine
100 + (0.028)
3
72+
2
100 + (0.0-35) 85+
(UCi/g wet injection injection. i.p.
3
(in
2
tissue). 10 days
25 mg/kg
before
unlabelled
sacrifice compound),
346
J. Duhault
et al.
Table
6
to synaptosomes 14C Fenfluramine and p4 C] 5 HT binding treatment, expressed as percent of controls.
in
vitro,
[14C]Fenfluramine 20 IJM
Groups
Controls
100
10 days
P4CI
Values in brackets 5.6 DHT (8 rats) Controls
(8
rats)
DHT
represent 75 Ug : 20 ~1
:
labelled in 20~1, saline,
+ 2
compound intraventricular
Release
of
fl
I4 C
DA from
rat
10-g 10-8 lo-'
5.10-7 lo-6 5.10-6 10-5 10-4
* p *
0.05
( llM/mg injection
intraventricular
neostriatal
Increase Dose
48
bound
+ 3,3
protein/min) 10 days
before
injection
Table
7
synaptosomes
after
anorectic
drugs.
- in
[14C-JDA
Fenfluramine
release.
% of 1
controls
Amphetamine
4.5
11 9.3
3.6
12.9.
7.95
7.7 0
7.7
3
30.4. 36.6. 48.5'
16.2. 34.2*
OHT
100 + 2 (0,017)
+ 5
82
5,6
5 HT PM
0.42
(2,301 5,6
after
6.2
sacrifice
Anorectic
drugs
and
brain
monoamines
Fenfluramine d&d not modify release of DA at lower concentrations whereas at 10 M DA release was significantly higher thanincontrols the same experiment. These results suggest the possibility of nergic system after high doses of fenfluramine. The results presented above confirm drugs act through different mechanisms involved in control of feeding behavior.
and extend previous , and illustrate
that
an
observations several
347
(5.10W7# run influence
and 10T7 M) simultaneeusly on the dopam+
that various neurotransmitters
in
anorectic are.
The importance of catecholamines in the regulation of feeding processes has heenrecogntzed for over 20 years, but the role of the serotoninergic system was more recently suspected, As is well known in the rat, intraventricular injection of noradrenaline stimulates rather than inhibits feeding, and a substance stimulating central a adrenoceptors (cloni'dine) also stimulates feeding in rats. This effect is antagonised by aadrenoceptor blockin agents (Le Oouarec et al., 1972). Therefore, noradrenergic mechanisms are unlikely to p %ay a major role in mediating anorectic responses to drugs. As previously reported (Kruk, 1973) activation of dopamine receptors by direct application of dopamine, or with a direct receptor agonist, apomorphine or pirlibedfl, produced anorexia. Pimozide, a dopamine receptor blocker, antagonized the anorectic effect of these drugs and suggested involvement of the dopaminergic system in the regulation of food intake. On the other hand, according to Kruk (1973), intraventricular injection of 5-HT inhibits food iintake, and Blundell reported anorectic activity of the serotonin precursor 5-HTP (Blundel and Lesham, 1975). Such an effect is blocked by pretreatment with the 5-HT antagonists cyproheptadine ormethysergide. These observations suggested the existence of a serstonfnergic system regulating feeding center activity. Arising from this possibility, serotontnergic agonists could be active in reducing food consumption and the activity of some anorecttc agents could be mediated by the 5-HT system. A number of recent studies supports the hypothesis that 5-HT is involved in the anorectic action of fenfluramine (Jespersen and ScheeilKruger, 1973, Ghezzi et aZ., 1973, Duhault 19751. Metheraoline (Funderburk et ~2.. 19711 and CvDroheDtadine (Kruk, 19731 were reoorted to antagonize-the anorectic properties-of fenfluram%e, but conflicting resuits were re orted after methysergide pretreatment (Blundell and Lesham, 1975, Schmitt, 1973), pro6ably re P ated to the delay after antagonist administration. As shown in the present study, the reduction in food intake induced by fenfluramine was not antagonized by an a adrenoceptor blocking agent (dibenamide) or dopamine-receptor blocking agent (pimozide), but clomi‘prami'ne administered 30 min before fenfluramine reduced the anorectic effect of this drug only. Interestingly enough, Lilly 110-140 and to a lesser extent quipazine, potentiate the anorecttc effect of 5-HTP but only Lilly 110-140 has additive effect with fenfluramine. Fenfluramine activity through a serotoninergic system was supported by investigation on the synaptosanal uptake. As revealed by d b e reciprocal plots, fenfluramine pretreatment competitively-6 inhibited the uptake of[ a C 1 5 HT for an initial concentration between 0.1 and 0.5 x 10 M. The apparent Michaelis constant is 0.116 + 0.006 x lo-6M for the control group and 0.2192 0.037 x 10-6 for the fenfluramine treated group (Duhault et al., 1978). In vivo experiments confirm that fenfluramine is a competitive affinity uptake of 5-HT into brain synaptosomes. Fenfluramine selective inhibitor for 5-HT uptake, Lilly 110-140. Similarly, ted the reuptake process in synaptosomes (Hamon et al , 1976) serotoninergic terminals as suggested by the lack of inhibition
inhibitor of the high shares thts activity with a quipazine competitively i'nhi%iand had direct effects en of clcmipramtne pretreatment,
The functional integrity of the serotoninergic system is required for fenfluramine actl+fi'ty since parachloroamphetamine, a 5 HT neurotoxin, has been reported to produce a long lasting depletion in brain serotonin and a decrease of the anorecti'c activity of fenfluramine l'n rats (Ouhault and Boulanger, 1977). Such a neurotoxic effect was suspected by Harvey et at., 1977, after acute fenfluramine administration. Fenfluramine was shown to have less of an effect than PCA on brain 5-HT, of shorter duration (Duhault and Boulanger, 1977). On the other hand, no neuronal abnormality or glial reaction was observed in the brain (B 8 - B 9 areas) of rats sacrificed either after acute administration or cumulative doses of fenfluramine (OliVfer et al., 1978 : Lorez et al., 1978). Since we failed to reproduce the findings of Harvey (dark neurones and perineuronal spaces enlargement) in the B 9 area of the brain of fenfluramine treated rats, it is suggested that these neurotoxic aspects are related to a fixative artefact as reported by Cammermeyer (1962).
343
J. Duhault
et al.
A new anorectic compound, MK 212 (Clineschmidt et UZ., 1977) acts mainly via the serotonibut fails to decrease brain 5 HT. On the other hand, nergic system, resembling fenfluramine, the anorectic action of MK 212 was antagonized by prioradministration of methergoline or 1978), but in rats previously treated with clomipramine cyproheptadine (Clineschmidt et al., the activity of MK 212 was unaffected. In this respect, MK 212 differs from fenfluramine and could be suspected as a direct serotonin-mitrectic agent, at least in certain brain areas. The integrity of neuron systems projecting into or passing through the hypothalamus has Intraperitoneal injection of d-amphet been shown to be essential for food intake regulation. amine or mazindol causes a dose dependent decrease in the food eaten in the 2 h following presentation. Their anorectic effect was abolished following pretreatment with pimozide 30 min before the anorectic agent. Neither clomipramine nor 5 HTP significantly affected feeding responses, whereas dibenamine slightly reduced amphetamine potency only. Both anorectic drugs were potent inhibitors of dopamine and norepinephrine uptakes. These results were consistent with those presented by Krug and Zarrubdast (1976) indicating that amphetamine and mazindol were more potent as inhibitors of uptake than as releasers of monoamines. In addition, since stimulation of dopamine receptors with a direct receptor agonist (Barzaghi et ~2, 1973) produced inhibition of food intake, we re-emphasize that activation of dopamine receptors can mediate anorectic responses to some anorectic drugs. Conclusion To conclude, the mechanism of action of anorectic drugs appears more complex than previously increases and decreases in central dopaminergic activity can reduce feeding suspected : both and experimental results support the hypothesis of the noradrenergic function in the regulation of food intake. The involvement of serotonin systems in feeding is well established (Blundell 1977) but observations suggest that the tryptaminergic system might regulate the activity of Awazi and Guidberg, 1978)) therefore alteration dopaminergic neurons (Fuenmayor-T, 1978, of functional activity in the 5 HT systems after anordic drugs could modify the balance leading to an inhibitory effect on feeding. between dopamine or noradrenaline and serotonin,
References AWAZI, N. tryptamine
and
phnrmacol.
GUIDBERG, H.C. (1978). with dopamine metabolism
On the interaction in the rat striatum.
of
5-hydroxytryptophan flnunyz-Schmiedeberg's
and
5-hydroxyarch
303 : 63-72
BARZAGHI, F.,aPPETTI, A., MANTEGAZZA, P. and MULLER, E.E. (1973) Reduction of food intake by apomorphine, a pimozide sensitive effect. J. Pharm. Pharmac. 25 : 909-911, BELIN, M.F., KOUYOUMDJIAN, J.C., BAROAKDJIAN, J., DUHAULT, J. and GONNARD;-P. (1976) Effects of fenfluramine on accumulation of 5-hydroxytryptamine and other neurotransmitters into synaptoscmes of rat brain. Neyoptiacolpgy 15 : 613-617. BLUNDELL, J.E. and LESHAM, M.B. (1975) Biphaslc a%ion of a 5-hydroxytryptamine inhibitor on fenfluramine-induced anorexia. J. Ph. Pkarmac. 25 : 492-494. BLUNDELL, J.E. (1977) Is there a role for serotonin Fhydroxytryptamine) in feeding ? Intern. J. Obesity 1 : 15-42. CAMMERMEYER, J. (1962r An evaluation of the significance of the "dark" neuron. Rev. Anat. Embryol. Cell Biol. 36 : 1-61 CLINESCHMIDT, B.V., HANmN, H.M., PFLUEGER, A.B. and MC GUFFIN, J.C. (1977) anorexigenic and ancillary action of MK 212 (6-chloro-2-l-piperazinyl-pyrazine ; CPP). i%ychophamtlacology 55 : 27-33. CLINESCHMIDT, B.V., MC GUFFIN, J.C., PFLUEGER, A.B. and TOTARO, J-A. (1978) A 5-hydroxytryptamine-like mode of anorectic action for 6-chloro-2-lpiperazinyl-pyrazine (MK 212). BP. J.
Phc.
62 : 579-589.
DUHAULT, J.;LBDULANGER, M., VOISIN, C., MALEN, Ch. and SCHMITT, H. (1975) Fenfluramine and 5-hydroxytryptamine. Part 2 : Involvement of brain 5-hydroxytryptamine in the anorectic activity of fenfluramine. Anneim. FOPS&. 25 : 1758-1762 DUHAULT, J., and BOULANGER, M. (1977) Fenfluramine long-term administration and brain serotonin. Europ. J. Pharmacol. 43 : 203-205 DUHAULT, J., BEREGI, L., GONNARD, r and BOULANGER, M. (1978) Brain serotoninergic system and anorectic drugs. In : Central mechanisms of anorectic drugs (1978) S. Carattini, and
R. Samanin,
(E&T),
pp 205-215
Raven Press,
N.Y.
Anorectic
drugs
and
brain
monoamines
349
FUENMAYOR, T.L. (1978) Effect of a reduction in brain 5rhydroxytryptamine on the concentration of homovanillic acid in the rat caudate nucleus. Er. J. Phamnac. 63 : 391 P FUNOERBURK, W.H., HAZELWOOD, J.C., RUCKART, R.T. and WARD, J.W. (197T) Is 5-HT involved in mechanism of action of fenfluramine ? J. Pharm. PharmKlcoZ. 23 : 468-469 GHEZZI, D., SAMANIN, R., BERNASCONI, S., TOGNONI, G., GERNA, K and GARATTINI, S< (1973) effect of thymoleptics on fenfluramine induced depletion of brain serotonin in rats.
Eur.
J. Pharmacol.
GRAY, E.G. microscopic
and
the
24 : 205-210
WHITTAKER, V.P. (1962) study of cell fragments
The isolation derived by
of nerve homogenisation
endings and
from brain centrifugation.
and
electron
J. Anat.
96 : 79-87 HAF16N, M., BOURGOIN, (1976) The effects
S., ENJALBERT, A., BOCKAERT, J., of quipazine on 5 HT metabolism Arch. Pharmacol. 294 : 99-108 HARVEY, J.A., MC MASm, S.E. and FULLER, R.W. (1977) serotonin depleting effects of various halogenated
J. PharmacoZ.
Earp. Ther.
in
HERY, the
F., rat
Comparison derivatives
TERNAUX, J.P. and GLOWINSKI,J. brain. flaunyn-Schiedeberg's between the neurotoxic of amphetamine in the
and rat.
202 : 581-589
JESPERSEN, S. and SCHEEL-KRmER, J. (1973) Evidence for a difference in mechanism of action between Fenfluramine and amphetamine induced anorexia. J. Phamn. Phurmuc. 25 : 49-54 KRUK, Z.L. (1973) Dopamine and 5-hydroxytryptamine inhibit feeding in rats. ii%ure, 246 :5X53 KRUK, Z.L. and ZARRUBDAST, M.R. (1976) The effects of anorectic drugs on uptake and Tease of brain monoamines. Brit. J. Pharm~col. 58 : 272 P - 273 P LE OOUAREC, J.C., SCHMITT, H. and LUCET, B.71972) Effects de la clonidine et d'autres agents sympathomimCtiques sur la prise de nourriture : antagonisme par desagents adrenolytiques. J. Pharmacol. (Paris) 3 : 187-198 LOREZ, H.P. , SANER and RICHARDS, J.G. (1978) Evidence against a neurotoxic aCti’On of halogenated amphetamine on serotoninergic B9 cells. A morphometric fluorescence hfstochemical study. Brain Res. 146 : 188-194 OLIVIER, L. DU BOISTESSELIN, Rxnd DUHAULT, J. (1978) Lack of neurotoxicity in fenfluramine anorexia. IRCS Journal of Med. Science. 6 : 463. SCHMITT, H. (1973) Influence d'agents inteFf&ant avec les catecholamines et le 5+ydroxytrypamine sur les effets anorexiques de l'amphetamine et de la fenfluramine. J. PharmacoZ. (Paris) 4 : 285-294.
Inquiries
and
reprint
Dr. 3. Duhault Institut de Recherches 14 Rue du Val d'Or 92150 Suresnes France
requests
Servier
should
be
addressed
to
: