Abstract |
Administration of L-5-hydroxytryptophan (25 mg/kg body weight, SC) to female rats resulted in copious drinking. The dipsogenic response to administration of L-5-hydroxytryptophan (5-HTP) was blocked by propranolol (6 mg/kg body weight, IP), a beta-adrenergic antagonist, and captopril (35 mg/kg body weight, IP), an angiotensin converting enzyme inhibitor. In addition, clonidine (12.5 and 25 microgram/kg body weight, IP), a central alpha-adrenergic agonist known to inhibit renin release, attenuated drinking during 1, 2 and 3 hours after 5-HTP was administered. These results suggest that 5-HTP-induced drinking is mediated by way of the renin-angiotensin system. Haloperidol (150 microgram/kg body weight, IP), a dopaminergic antagonist, also attenuated the dipsogenic response to administration of 5-HTP. In addition, incremental reductions in 5-HTP-induced drinking with increasing doses of spiperone (37.5 to 150 microgram/kg body weight, IP), a more potent dopaminergic antagonist, were demonstrated. Thus, the dipsogenic response to administration of 5-HTP to rats is dependent on both the renin-angiotensin system and an intact dopaminergic pathway.
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Authors | R M Threatte, M J Fregly, T M Connor, D C Kikta |
Journal | Pharmacology, biochemistry, and behavior
(Pharmacol Biochem Behav)
Vol. 14
Issue 3
Pg. 385-91
(Mar 1981)
ISSN: 0091-3057 [Print] United States |
PMID | 7015366
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Spiperone
- Captopril
- Propranolol
- 5-Hydroxytryptophan
- Haloperidol
- Clonidine
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Topics |
- 5-Hydroxytryptophan
(pharmacology)
- Animals
- Captopril
(pharmacology)
- Clonidine
(pharmacology)
- Drinking
(drug effects)
- Drug Interactions
- Female
- Haloperidol
(pharmacology)
- Propranolol
(pharmacology)
- Rats
- Spiperone
(pharmacology)
- Stimulation, Chemical
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