[Blood vessels of the hypophysis]

The construction of the intraorganic vessels of the hypophysis was studied by different injectional methods in cats and partly in dogs. The obtained data confirmed the portal microcirculation in the hypophysis of the animals under investigation. Anatomical and some experimental data speak in favour of the blood flow direction in the portal system from the medial eminence towards the anterior part of the adenohypophysis. The capillaries of the portal system were demonstrated to anastomose with arcuate nucleus of the hypothalamus and with the caudal parts of the neurohypophysis. The experiments with intravital accumulation of the trypan blue revealed macrophagal activity of the perivascular connective tissue elements of the portal system. An attempt was made to objectively analyze the capillary architectonics of the hypophysis portal system. The obtained data on its peculiar features are discussed in connection with the capillary construction and peculiarities of the metabolism of the hypothalmic neurosecretory nuclei.