[Reaction of the neurosecretory system of dogs with reno-vascular hypertension in the postnatal ontogenesis].

In dogs of different age with simulated renovascular hypertension neurosecretion of the hypothalamo-neurohypophysial system was studied. Experiments were conducted with puppies 18-22 days, 11/2-3 months and dogs 3-5 years old. It was established that in the ontogenesis of dogs the differentiation of neurons in the supraoptic nucleus occurred earlier than that of cells in the paraventricular nucleus. The simulation of hypertension accelerates the differentiation of tbe neurosecretory cells. The development of arterial hypertension leads to prevalence of precesses of the neurosecretory material outflow over the latter's synthesis, irrespective of the maturity of the neurosecretory system. With the arterial pressure stabilized at a high level a concordance between an elevated synthesis of the neurosecretion and its increased outflow is noted. Visual evaluation of the activity is supported by the results of cellular micrometry.