Anti-serotonergic effects of urethane and chloral hydrate may not be mediated by a blockade of 5-HT2 receptors. Short communication.
The general anesthetics urethane and chloral hydrate have profound anti-serotonergic effects both in the rat cortex in vivo and the rat aortic ring in vitro. The suggestion that these effects may be due to an action on 5-HT2 receptors was tested using ex vivo and in vitro [3H]ketanserin binding assays with membrane-enriched fractions from rat brain. Urethane did not alter [3H]ketanserin binding in the ex vivo assay. In the in vitro assay, urethane, chloral hydrate, and its active metabolite 2,2,2-trichloroethanol produced slight reductions (of 16%, 9%, and 18%, respectively) of [3H]ketanserin binding. These studies suggest that anti-serotonergic effects of urethane and chloral hydrate may not be mediated by a blockade of 5-HT2 receptors.
Dringenberg
H C
HC
Neuroscience Program, University of Western Ontario, London, Canada.
Baker
G B
GB
Urichuk
L J
LJ
Vanderwolf
C H
CH
D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D000818:Animals; D001667:Binding, Competitive / Q000502:physiology; D002697:Chloral Hydrate / Q000494:pharmacology*; D005023:Ethylene Chlorohydrin / Q000031:analogs & derivatives / Q000494:pharmacology; D007650:Ketanserin / Q000378:metabolism / Q000494:pharmacology; D008297:Male; D008565:Membrane Proteins / Q000037:antagonists & inhibitors; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000378:metabolism; D012702:Serotonin Antagonists / Q000494:pharmacology*; D009435:Synaptic Transmission / Q000187:drug effects; D014316:Tritium; D014520:Urethane / Q000494:pharmacology*
D018686:Anesthetics, Intravenous; D008565:Membrane Proteins; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D014316:Tritium; D014520:Urethane; D002697:Chloral Hydrate; D005023:Ethylene Chlorohydrin; D007650:Ketanserin; C005849:2,2,2-trichloroethanol