ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
The binding of serotonin to a soluble, high affinity binding protein, present in synaptosomes and associated with serotonergic tracts, has now been studied for the effects of metallic ions and various drugs. At optimal concentration (10-4 M) of Fe2+ the enhancement of binding was close to 20-fold. A much smaller effect was noted with Cu2+. With other ions (Fe3+, Mn2+, Co2+, Ni2+, Cr3+, Mg2+, Ca2+) little or no effect was seen. For the effect with Fe2+. preincubation was required (10 min, 25°C) and concentrations higher than 10-4M were inhibitory. Studies based on equilibrium dialysis show that the effect of Fe2+ was on the affinity of the binding of serotonin to the protein, rather than on the binding capacity. In polydcrylamide gels at pH 8.6 the migratory properties of thc serotonin-protein complex formed in the presence of Fe2+ differ from those of the complex formed without Fe2+. Nucleotides (ATP, GTP, ADP, AMP) inhibited thc binding. The effects of several classes of drugs (inhibitors of biogenic amine storage and uptake, psychotomimetics, MAO) inhibitors and drugs binding to contractile proteins) were also studied. The only effective inhibitors of serotonin binding were reserpine, vinblastine and CZ-74, which caused 50% inhibition at 2 × 10-6 M, 7.5 × 10-6 M and 0.2 × 10-6M respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1976.tb06467.x
