Fedirko N. Mechanisms maintaining the calcium homeostasis in acinar cells of submandibular salivary gland.

The dissertation is devoted to studying the mechanisms of Ca2+ homeostasis in cells of rat submandibular gland in physiological and pathological conditions. It was shown that acetylcholine-induced [Ca2+]i transients are deter-mined by superposition of Ca2+ release from endoplasmic reticulum, Ca2+ reuptake and influx. Mitochondria regulate Ca2+ release from reticulum by preventing Ca2+-dependent inactivation of InsP3 receptors. We showed the functioning of P1 and P2 purinoreceptors. We first showed the pres-ence of functionally active ryanodine receptors and captur-ing of released Ca2+ by mithochodria. We showed the pas-sive leak via translocon. We first showed that mitochon-dria define the store-operated Ca2+ influx. We found the changes of Ca2+ homeostasis in acinar cell under experi-mental diabetes: rise in [Са2+]і, sensitivity of cholinoreceptors, decrease in the Ca2+-ATPases activity. We first found the impairment of Ca2+ homeostasis inside Ca2+ stores under diabetes. Thus, the Ca2+ homeostasis ismaintained by coordinated activity of Ca2+-regulating systems, while its impairment causes the development of salivary glands' disorders.