Head injury, stroke, hypoxia or ischemia are all possible causes, which lead to formation of cytotoxic cerebral edema (cell swelling). Astrocytes are among the first brain cell types to undergo swelling, which may lead to neurodegeneration. To this day, there is no medical treatment to reduce astrocyte swelling and formation of neurodegeneration. Noradrenergic stimulation, which activates adrenergic receptors (α-AR in β-AR) on astrocyte plasmalemma, acts favorable to reduce cell edema. Noradrenalin may be a candidate for treatment of cytotoxic edema, however, mechanisms of its action on cell response are not clear yet. We used an electrophysiological method, patch clamp in the whole cell configuration, to better understand processes affecting cell surface fluctuations, after noradrenalin stimulation on cultured cortical rat astrocytes. We have monitored the parameter of cell capacitance (C_m). After stimulation the C_m has increased significantly. It is known that astrocytes secrete their gliotransmitters also in the process of 〖Ca〗^(2+) dependent exocytosis. Noradrenalin activates α_1-AR, which increases intracellular calcium concentration. We concluded that the rise in C_m parameter was due to activation of the process of exocytosis
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