Seymour M. Glick

A calcitonin radioimmunoassay: In vivo evaluation of calcitonin secretion in the pig

Abstract A radioimmunoassay capable of measuring porcine calcitonin (CT) in unextracted porcine plasma has been developed. A guinea pig antiserum to partially purified porcine CT was highly specific for CT and was capable of detecting 0.025 ng/ml of porcine CT. The antiserum cross-reacted significantly with sheep CT and beef CT but not with monkey CT or rabbit CT. The mean fasting CT concentration in 25 samples from the internal jugular vein of four pigs was 0.93 ng/ml (range, 0.46–1.61 ng/ml). An infusion of calcium ( 10–15 mg / kg 30 min ) was followed by an increase in plasma CT 3–10 ng.ml above base line in “responsive” animals and a rise of 0.5–1 ng/ml in less sensitive pigs.

Radioimmunoassay of Oxytocin

The development of immunoassays for the various peptide hormones has greatly enhanced our understanding of endocrine physiology. The present paper reports progress in the development of an immunoassay for the relatively small peptide hormone, oxytocin.