Binding of 5-hydroxytryptamine to brain hydrophobic proteins. Inhibition by structural analogues and ions.
Binding studies with hydrophobic proteins extracted from cerebral cortex homogenates by mixtures of n-butanol-water and separated by chromatography on LH-20 Sephadex, have been done. 5-HT-(14C) binds to this fraction with high affinity. This binding saturates with 5 X 10(-6) M 5-HT, with K1/2 value of 1 X 10(-7) M. Binding is partially inhibited by a mixture of alkaloids ergocornine, ergocrystine and ergocryptine, as well as by tryptamine. A light inhibition has been observed in presence of tryptophan or lysine, but none in presence of methysergide or hypoxanthine. Binding is strongly inhibited by monovalent ions (Li+, Na+ and NH4+). The influence of pH in the incubation medium has also been studied; maximal rates of binding were obtained at neutral pH.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002417:Cattle; D003864:Depression, Chemical; D004876:Ergot Alkaloids / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000494:pharmacology; D009185:Myelin Proteins / Q000378:metabolism*; D018991:Myelin Proteolipid Protein; D011485:Protein Binding / Q000187:drug effects; D012701:Serotonin / Q000031:analogs & derivatives / Q000378:metabolism*; D013329:Structure-Activity Relationship
D004876:Ergot Alkaloids; D007477:Ions; D009185:Myelin Proteins; D018991:Myelin Proteolipid Protein; D012701:Serotonin