The radioimmunoassay of several neuropeptides

Our laboratory has been engaged in developing radioimmunoassays for a variety of neuropeptides to be used primarily for serum analysis. Our experience in developing peptide RIAs is demonstrated in eight analysis systems using iodinated peptides, for somatostatin, methionine enkephalin, leucine enkephalin, alpha melanocyte stimulating hormone (MSH), substance P, neurotensin, bombesin, and beta-endorphin which are compared. The least detectable quantities vary from less than 0.1 picogram in the case of alpha-MSH to 50 picograms in the case of met-enkephalin. Our progress in assessing each system ranges from having only a basic RIA standard curve to defining reasonably exactly the serum or plasma concentration. Problems in assay development are discussed for the peptides: somatostatin, beta-endorphin, neurotensin, alpha-MSH, and bombesin. (Auth.)