Ability of the CRF immunoreactive neurons of the paraventricular nucleus to produce a vasopressin-like material. Immunohistochemical demonstration in adrenalectomized guinea pigs and rats.

In the paraventricular nucleus of normal or adrenalectomized colchicine-treated guinea pigs and rats, corticotropin-releasing factor (CRF), vasopressin (VP) and oxytocin (OX) immunoreactivities were compared. In the control animals, respective stainings for these three peptides are distinct. Adrenalectomy resulted in the appearance of a VP-like staining in most of the CRF-immunoreactive neurons whereas OX staining remained distinct. It is suggested that the CRF/VP coexistence reflects the synergistic role of the two peptides.