Species variations in 5-HT3 recognition sites labeled by 3H-quipazine in the central nervous system.
The specific binding of 3H-quipazine to putative 5-HT3 receptors was analyzed in multiple species. Specific and saturable binding of the radioligand could be detected in both rat (KD = 1.2 nM; Bmax = 3.0 pmol/g) and pig (KD = 1.3 +/- 0.2 nM; Bmax = 1.5 +/- 0.2 p/mol/g) cortical membranes. By contrast, no significant specific binding of 3H-quipazine could be detected in human, cow, dog, turtle, mouse, guinea pig, chicken or rabbit brain membranes. These data indicate that marked species variations exist in the presence and/or density of 5-HT3 membrane recognition sites in the central nervous system.
Peroutka
S J
SJ
Department of Neurology, Stanford University Medical Center, CA 94305.
D000818:Animals; D002417:Cattle; D002540:Cerebral Cortex / Q000378:metabolism*; D002645:Chickens; D003042:Cocaine / Q000494:pharmacology; D004285:Dogs; D006168:Guinea Pigs; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D051379:Mice; D011804:Quinolines / Q000378:metabolism*; D011814:Quipazine / Q000032:analysis / Q000378:metabolism*; D011817:Rabbits; D011869:Radioligand Assay; D051381:Rats; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000494:pharmacology; D013045:Species Specificity; D013552:Swine; D014326:Tropanes / Q000494:pharmacology; D000077526:Tropisetron; D014426:Turtles
D007211:Indoles; D011804:Quinolines; D011985:Receptors, Serotonin; D014326:Tropanes; D012701:Serotonin; D011814:Quipazine; D000077526:Tropisetron; D003042:Cocaine; C042253:bemesetron