MODELLING OF INSULIN RESISTANCE AND ACCOMPANYING METABOLIC DISTURBANCES WITH DEXAMETAZONE
L.L.Vavilova, T.A.Krjachok, T.V.Talaieva
National Scientific Center N.D. Strazhesko Institute Cardiology, Ukrainian Academy of Medical Sciences, Kyiv, Ukraine
In experiment carried out on 12 rabbits, the possibility of reproduction of insulin resistance syndrome components in the absence of obesity as initiating factor was assessed. The experimental rabbits were subjected to subcutaneous injections of synthetic glucocorticoid dexametazone during 8 weeks in the dose 15 mkg/kg. The obtained data showed a progressive decline in insulin sensitivity in the course of the experiment, and at the end of the 8-th week the reaction to subcutaneous insulininjection decreased by 82%, the content of glycosilated hemoglobin increased by 200%. These changes were accompanied by increased Tg content in blood by 67%, the contents of total cholesterol and free fatty acids were increased by 109% and 176%, respectively. The C-reactive protein content in blood increased 12,5 times, indicating intensification of systemic inflammation, and the activity of angiotensin-converting enzyme increased by 215%. These changes were noted in the absence of body weight shifts indicating on the possibility of insulin resistance development as the result of primary disturbances in intracellular lipid metabolism in the absence of systemic obesity, which promotes the development of insulin resistance but does not trigger it.
insulin resistance, obesity, systemic inflammation, metabolism, glucocorticoids
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