Kolicheva N. Pathogenetical role of catecholaminergic system of the suprarenal glands in the development of exerimental diabetes mellitus

The thesis is devoted to the solving of one of actual problems of modern pathological phisiology. It consists in studying of the importance of catecholamine-dependent mechanisms in the development streptosotocin-induced diabetes in experiment. Acute hypoglycemia is proved to result in an increase of functional activity of catecholaminergic system of suprarenal and pancreatic glands which is revealed by high concentration of catecholamine in homogenates and increased concentration in plasma. It has been established that the initial period of development of exerimental diabetes in accompanied by phase dynamics of alteration in the concentration of biogenic amines in plasma, suprarenal and pancreatic glands with dominated content of adrenalin in catecholamine part, negatively correlating with glycemia level. The initial period of the experimental diabetes accompanied by the increase of endocrinocyte density in fascicular and reticular zones of suprarenal cortical substance, the growth of RNA concentration in them and the increase of blood cortisol level. The elevation of NO-synthase activity and stable NO-metabolite concentration in suprarenal glands of diabetic animals is proved to be noticed and combined with the decrease of catecholamine content this should be considered as stress-limiting link. It has been shown that the injection to intact rats of L-tyrosine results in the increase of adrenaline and noradrenaline concentration in their blood as well as the increase of glucose concentration. The injection to diabetic animals of L-tyrosine does not influence the glucose and insulin level in their blood but results in the decrease of adrenaline and noradrenaline concentration in blood and suprarenal glands. It has been revealed that injection to intact and diabetic animals of methil-L-thyrosin inhibits monoamine synthesis in suprarenal glands and results in the reduction of summary part of catecholamine in glands and blood and it goes with authentic reduction of glycemia level.