[Role of hypothalamic adrenoreactive structures in regulating the protective reaction to plasmin].

Electrical stimulation of the hypothalamic dorsomedial and wentromedial nuclei induced an activation of the coagulating system in rats. Plasmin in the vascular bed increased the electrical activity of medial and mamillary hypothalamic neurons, the activity coinciding in time with the maximal level of the blood hypercoagulating response. The activation does nor occur after plasminogen administration. The activation of the blood coagulating system is due to an excessive amount of plasmin in the blood and can be suppressed with sympatholytic agents. The plasmin-induced electrical activity is suppressed with aminasin whereas phentolamine administration does not affect the activity though no activation of coagulating system occurs. Absence of humoral hypercoagulating shift in the blood confirms participation of alpha-adrenoreception in peripheral efferents. The increased efferent sympathetic activity seems to be the cause of plasmin-induced hypercoagulation.