Comparison of binding sites for the calcitonin gene-related peptides I and II in man.
Specific and saturable binding sites of the synthetic human calcitonin gene-related peptide-I (CGRP-I) and -II (CGRP-II) have been identified in membrane homogenates of the human central nervous system, heart and spleen. Half maximal inhibition of the binding of 125I-CGRP-II was achieved with 0.25 nM and 1.7 nM of non-radioactive CGRP-I or -II, and with 260 and 850 nM salmon calcitonin in the spinal cord and cerebellum, respectively, but 1 microM human calcitonin was not recognized. Autoradiographs of diencephalic sections revealed different distribution of 125I-CGRP-I and -II binding sites.
D001345:Autoradiography; D001665:Binding Sites; D015740:Calcitonin Gene-Related Peptide; D002490:Central Nervous System / Q000378:metabolism*; D006801:Humans; D007457:Iodine Radioisotopes / Q000378:metabolism; D007700:Kinetics; D009206:Myocardium / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism*
D007457:Iodine Radioisotopes; D009479:Neuropeptides; D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface; D015740:Calcitonin Gene-Related Peptide