title: The uptake of 6-methoxy-1,2,3,4-tetrahydro-beta-carboline and its effect on 5-hydroxytryptamine uptake and release in blood platelets.
abstract: The uptake of 6-methoxy-1,2,3,4-tetrahydro-beta-carboline (6-MeOTHBC, 5-methoxytryptoline) by rabbit blood platelets was studied by using 3H-labelled compound. A high rate active uptake (Km 6.6 micron), which was inhibited by 5-hydroxytryptamine (5-HT) and cinnanserine, and a slow rate uptake, not inhibited by 5-HT were observed. The intracellular distribution of 3H-6-MeOTHBC in platelets clearly differed from that of 14C-5-HT. 6-MeOTHBC also competitively inhibited the high-rate active (but not the slow passive) uptake of 14C-5-HT, being more active than 5-HT itself. The spontaneous release of the newly taken-up 14C-5-HT from platelets was increased only with high concentrations of 6-MeOTHBC.
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000378:metabolism*; D002243:Carbolines / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D002928:Cinanserin / Q000494:pharmacology; D007211:Indoles / Q000097:blood*; D010042:Ouabain / Q000494:pharmacology; D011817:Rabbits; D012701:Serotonin / Q000097:blood*; D013997:Time Factors
chemical_list: D002243:Carbolines; D007211:Indoles; D012701:Serotonin; D010042:Ouabain; D002928:Cinanserin