Effects of 8-hydroxy-2-(di-n-propylamino)tetralin, a selective agonist of 5-HT1A receptors, on the cough reflex in rats.
The effects of the agonist of 5-HT1A receptors, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), on the capsaicin-induced cough reflex in rats were studied. I.p. injection of 8-OH-DPAT, at doses of 0.1 and 0.3 mg/kg, significantly decreased the number of coughs in a dose-dependent manner. The antitussive effect of 8-OH-DPAT (0.3 mg/kg) was blocked by prior injection of methysergide (3 mg/kg i.p.) and spiperone (0.3 mg/kg i.p.), whereas ketanserin (3 mg/kg i.p.) had no effect on the antitussive effect of 8-OH-DPAT. The antitussive effects of dihydrocodeine (1 mg/kg i.p.) and dextromethorphan (3 mg/kg i.p.) were also antagonized by methysergide and spiperone. However, these cough-depressant effects were not reduced by ketanserin. These results suggest that the antitussive action of 8-OH-DPAT may be related to the enhancement of the function of 5-HT1A receptors, and that antitussives interact with the 5-HT1A receptors.
Kamei
J
J
Department of Pharmacology, School of Pharmacy, Hoshi University, Tokyo, Japan.
Mori
T
T
Igarashi
H
H
Kasuya
Y
Y
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D000996:Antitussive Agents / Q000494:pharmacology; D002211:Capsaicin / Q000494:pharmacology; D003061:Codeine / Q000031:analogs & derivatives / Q000494:pharmacology; D003371:Cough / Q000188:drug therapy* / Q000503:physiopathology; D003915:Dextromethorphan / Q000494:pharmacology; D004347:Drug Interactions; D007274:Injections, Intraperitoneal; D007279:Injections, Subcutaneous; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000502:physiology*; D012018:Reflex / Q000187:drug effects* / Q000502:physiology; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D000996:Antitussive Agents; D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; D003915:Dextromethorphan; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; C014481:dihydrocodeine; D002211:Capsaicin; D003061:Codeine