| Abstract: | 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. |
