Stability of [Asu1,7]-eel calcitonin and eel calcitonin in vitro and in vivo

Stability of [Asu1,7]-eel calcitonin was compared with that of eel calcitonin by the radioimmunoassay method. [Asu1,7]-Eel calcitonin cross-reacted with anti-eel calcitonin antisera. [Asu1,7]-Eel calcitonin was as stable as eel calcitonin in rabbit liver or rabbit kidney extracts when incubated at 37 degrees C. Disappearance curves from the plasma of [Asu1,7]-eel calcitonin and eel calcitonin following iv injection in rabbits were quite similar.