Down Regulation of Angiotensin II Receptor AT₁ Expression in the Pancreas of Diabetic Rat

Abstract

The renin-angiotensin system (RAS) is altered in diabetes. The aim of our study was to investigate whether streptozotocin-induced diabetes was associated with a change in angiotensin II receptors AT₁ and angiotensin-converting enzyme (ACE) mRNA expression in the pancreas in vivo. Rats were synchronized to a 12:12 light:dark cycle. Pancreas tissue sampling was done at 4 h intervals during 24 h cycle starting 17 days after streptozotocin (STZ) treatment (65 mg/kg of body weight). Real time PCR showed decreased expression of ACE in the pancreas after STZ administration during the dark phase. Expression of AT₁ was decreased in diabetic rats during the light and the dark phase of 24 h cycle. Our data show down-regulation of the pancreatic RAS during early stage of diabetes development.

ACE - angiotensin - per2 - bmal1 - streptozotocin

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