Down regulation of angiotensin II receptor AT1 expression in the pancreas of diabetic rat.

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 AT (1) 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 AT (1) 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. J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart.New York.