Comparison of the Pharmacological Characteristics of 2-[125I]Iodomelatonin Binding Sites in the Lung, Spleen, Brain and Kidney of Chicken

We have compared the pharmacological characteristics of 2-[125I]iodomelatonin binding to crude membrane preparations of the lung, spleen, brain and kidney of chicken. Saturation studies indicated significant differences (p < 0.05) in the equilibrium dissociation constant (Kd) and maximum number of binding site (Bmax) values among the four tissues studied. The descending order of affinities was lung = spleen > brain > kidney. Competition curves of 2-[125I]iodomelatonin binding to crude membrane preparations of all four chicken tissues by melatonin were studied simultaneously to reduce individual, physiological, age and interassay …