Activities of the anterior hypothalamus neurosecretory nuclear enzymes in exposure to organophosphorus compounds

Under study were activities of glycolysis enzymes: LDH, Crebs cycle SDH, those of electron transport system NAD and NADP-diaphorase, and of the hydrolytic enzymes, acid and alkaline phosphatases in the hypothalamus, as were morphofunctional shifts in these enzymes activities in poisoning with organophosphorus compounds. The experiments were carried out in 72 white male outbread rats weighing 180-200 g, that were administered PHOS antio (an organophosphorus compound) in a daily dose of 0.1 LD50 for 30 days. Early dates of poisoning were associated with an essential rise of the redox enzymes and a lowering of the hydrolytic enzymes levels, this being parallelled by morphologic signs of activation of the neurosecretory cells. Later high levels of neurosecretory material in the neurosecretory nuclei and reduced counts of neurosecretory cells were coupled with almost all the enzymes activities lowering. This permits a conclusion that changed activities of the enzymic systems may be one of the pathogenetic mechanisms and possible causes of neurosecretory cell dysfunction in pesticide poisonings

Vasopressin, oxitocin, and corticoliberin-synthesizing hypothalamic structures in rats of both sexes with induced diabetes mellitus

The endocrine status of the pancreas and the hypothalamic neurosecretory nuclei were studied by radioimmunoassay, immunocytochemical, morphometric and histochemical methods in Wistar rats of both sexes with experimental diabetes mellitus. The development of diabetes mellitus was characterized by beta-cell destruction and insulin concentrations reduction in these cells and the blood, by increase of glucagon and somatostatin levels in the alfa- and delta-cells, respectively, as well as by the growth of these substances concentrations in the peripheral blood. These changes were parallelled by activation of the vasopressin-, oxitocin and corticoliberin-synthesizing neurones of the paraventricular and supraoptic nuclei of the hypothalamus, as evidenced by morphometric findings and by increase of the blood vasopressin and corticoliberin concentrations and oxitocin level in the hypothalamus. Experimental diabetes mellitus was found to be characterized by activation of the hypothalamo-hypophyseo-adrenal system. Functional differences in the contribution of vasopressin- and oxitocin-synthesizing neurones of the hypothalamic nuclei in the pathogenesis of the disease is shown, as are their sex-specific reactions.

Neurosecretory Hypothalamus-Endocrine Heart as a Functional System

Cardiac atrial neurosecretion is precisely regulated by cardiotropic protein-hormonal complexes, formed by neurosecretory nuclei of the hypothalamus. There is a close neurohumoral interrelation between the neuroendocrine heart and the hypothalamus.