Neurophysin in the brain and pituitary gland of normal and scrapie-affected sheep—I: Its localization in the hypothalamus and neurohypophysis with particular reference to a new hypothalamic neurosecretory pathway to the median eminence

摘要: By use of an immunofluorescence histochemical technique with a cross-species reactive antiserum to porcine neurophysin-II the precise localization neurophysin in pituitary gland and hypothalamic area brain sheep has been determined. Neurophysin was confined neurosecretory pathways originating from supraoptic paraventricular nuclei. The major pathway terminates neurohypophysis but addition second neurophysin-containing proceeds external infundibular zone median eminence-pituitary stalk is associated presence vasopressin. In affected hereditary degenerative disease known as natural scrapie, this supraoptico-paraventriculo-infundibular preserved hypertrophied, while posterior lobe degenerates. nuclei comprise at least two distinct morphologically similar neuronal populations differently by scrapie genome, one undergoing dissolution middle-age surviving becoming hyperactive. This premature ageing probably primary biochemical lesion affecting rate axonal flow vesicles their discharge synaptic terminals. Possible metabolic circulatory bases for such anomaly are considered. rostral caudal adenohypophysis supports view that vasopressin acting directly trophic-hormone releasing factor, possibly quick release adrenocorticotropic hormone growth hormone. relation neurophysin-rich aggregations Herring bodies turnover material discussed.