Roxindole, a dopamine autoreceptor agonist with a potential antidepressant activity. II. Effects on the 5-hydroxytryptamine system.
Roxindole (ROX) (EMD 49980, 5-hydroxy-3-[4-(4-phenyl-1, 2,3,6-tetrahydropyridyl(1))-butyl(1)]-indole, mesylate), a potent selective agonist of presynaptic dopamine receptors with clinical antipsychotic and antidepressant activity, was studied pharmacologically in rats (male Wistar) and mice (male Albino Swiss) with respect to its influence on the central 5-hydroxytryptamine (5-HT) system. ROX did not induce the 5-HT1A syndrome (flat body and forepaw treading) in rats, but partly antagonized the syndrome evoked by 8-OH-DPAT. The 8-OH-DPAT-induced hypothermia in mice (a 5-HT1A effect) was not inhibited by ROX. The drug evoked hypothermia, which was antagonized by pindolol, but not by (+)-WAY-100135. ROX did not inhibit the m-chlorophenylpiperazine-induced hypothermia in mice (a 5-HT1B effect), or the exploratory hypoactivity in rats (a 5-HT1C effect). Head twitches induced by a low dose of L-5-HTP were potentiated by ROX, whereas those induced by its higher dose were antagonized. ROX also antagonized the hyperthermia induced by fenfluramine or trifluoromethylphenylpiperazine at a high ambient temperature in rats (a 5-HT2A effect). The results obtained indicate that ROX inhibits 5-HT uptake and shows 5-HT2A antagonistic and probably a 5-HT1B agonistic activities.
Maj
J
J
Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland.
Kołodziejczyk
K
K
Rogóz
Z
Z
Skuza
G
G
D006916:5-Hydroxytryptophan / Q000494:pharmacology; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D018491:Dopamine Agonists / Q000494:pharmacology*; D005277:Fenfluramine / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D000078183:Oxindoles; D010879:Piperazines / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology
D000928:Antidepressive Agents; D018491:Dopamine Agonists; D007211:Indoles; D000078183:Oxindoles; D010879:Piperazines; D011725:Pyridines; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; C081293:WAY 100135; C018406:1-(3-trifluoromethylphenyl)piperazine; D005277:Fenfluramine; D012701:Serotonin; C059613:roxindole; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D006916:5-Hydroxytryptophan; C015068:1-(3-chlorophenyl)piperazine