The role of "invertors" (intracellular activators) in age-related changes in cell response to hormones
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Published on: January 8, 2015
1Institute of Gerontology, Academy of Medical Sciences of Ukraine, Kiev.
Abstract:
It has been shown that a number of hormones (insulin, testosterone, thyroxine, and adrenaline) can stimulate synthesis of plasma membrane regulators-- "invertors" in a cell. The synthesis of "invertors," which is under genomic control, decreases with age. As a result, insulin, testosterone, and thyroxine do not provoke Na,K-ATPase activation and plasma membrane hyperpolarization of hepatocytes and myocardiocytes in old rates. Also, due to desensitization of the heart to adrenaline, a smaller decrease occurs in adenylate cyclase activity in old animals. The Na,K-ATPase of plasma membranes of old animals maintain their ability to respond to the "invertors." The decrease in the synthesis of "invertors" represent an important mechanism of change in the cell's reaction to hormones.
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