Demonstration of neurophysin in the hypothalamo-neurohypophysial system of the normal and dehydrated rat by the use of cross-species reactive anti-neurophysins

Summary Antiserum raised against porcine neurophysin-II and ovine neurophysin-III has been shown to cross react with the three neurophysins of the rat. The antisera were used in the immunohistological demonstration of neurophysin in the posterior pituitary gland and the hypothalamic nuclei of a normal rat and a rat subjected to varying degrees of osmotic stress. Depletion of neurosecretory material from the neural lobe of the stimulated rat is also accompanied by a concomitant reduction in the neurophysin and vasopressin content of the gland. Neurophysin is present in the cytoplasm of both the supraoptic and paraventricular nuclei.This work was financed by the Zealand Medical Research Council and the Auckland Medical Research Foundation. We thank Miss V. Bailey for help with the photographs.