[Aminopeptidase activity in the neurons of the nodose ganglion of the vagus nerve in acute experimental emotional stress].

Histological investigation was carried out to study the activity of aminopeptidase (AMP) in neurons of the nodose ganglion of immobilized rabbits with acute experimental emotional stress induced by electrical stimulation of ventromedial hypothalamic nuclei and skin. On the basis of the pattern of cardiovascular reactions, two groups of animals were distinguished: resistant and susceptible to the stress effects. In control animals, AMP activity was found to vary in neurons of different size. The highest activity was recorded in large cells, whereas small cells showed the minimum activity. In resistant animals AMP activity was found to be on control level in all groups of nerve cells. In susceptible rabbits AMP activity rose significantly, with maximum increase of AMP activity being observed in the large and medium-sized neurons.