Benzodiazepine binding sites in human myometrium.
We report that membrane preparations of human myometrium possess binding sites for [3H] RO 5-4864, a specific ligand for the peripheral type of benzodiazepine receptors. Scatchard analysis shows a high-affinity binding site (Kd = 3.1 +/- 1.1 nM) and a class of low-affinity binding sites (Kd greater than 30nM) with positive cooperativity. Displacement and tryptic digestion experiments indicate that both these benzodiazepine binding sites are specific and proteic in nature. So benzodiazepines might exert their relaxant activity on uterine muscle directly at peripheral level through specific binding sites.
D000328:Adult; D001570:Benzodiazepinones / Q000378:metabolism*; D001665:Binding Sites; D002462:Cell Membrane / Q000378:metabolism; D002998:Clonazepam / Q000494:pharmacology; D003975:Diazepam / Q000494:pharmacology; D005260:Female; D005445:Flunitrazepam / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D008140:Lorazepam / Q000494:pharmacology; D008875:Middle Aged; D009215:Myometrium / Q000378:metabolism*; D011963:Receptors, GABA-A / Q000378:metabolism*
D001570:Benzodiazepinones; D011963:Receptors, GABA-A; C028513:4'-chlorodiazepam; D002998:Clonazepam; D005445:Flunitrazepam; D008140:Lorazepam; D003975:Diazepam