Postmortal degradation of neuropeptides in the neurohypophysis

Porcine neurophysin proteins as well as oxytocin and lys-vasopressin were extracted from fresh (immediately after death) and stored (10, 20 and 60 min, 6, 12 and 24 hours) pituitary posterior lobes. Analyses were performed by high performance liquid chromatography (HPLC). In fresh tissue all forms of neurophysin proteins were present, the pattern of distribution of the neurophysins, oxytocin and lys-vasopressin did not change during the period of storage while other unknown peaks showed degradation. Posterior pituitary glands can be used for the preparation of neurophysin proteins, oxytocin and lys-vasopressin within 24 hours after death.