Calcitonin gene-related peptide (CGRP) as a GH secretagogue in rat and human pituitary tumoral cells.

CALCITONIN gene-related peptide (CGRP), a 37amino-acid neuropeptide identified as a potent vasodilator [1], is widely distributed in the central nervous system. The presence of CGRP and its binding sites has been found in the pituitary [2-4], but its role in regulating pituitary function remains to be determined. In the present study, we investigated the effect of CGRP on the secretion of GH in vitro by using rat pituitary tumoral cells (GH3 cells) and human pituitary adenoma cells. 0.1% bovine serum albumin for 4 h. The medium was collected and stored at 20 °C until assayed. The concentrations of rat and human GH were measured by specific radioimmunoassay provided by NIDDK and with an immunoradiometric assay kit provided by Daiichi RI Lab, respectively. The results were expressed as the mean ± SEM.