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 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.

H2S Inhibits Hyperglycemia-Induced Intrarenal Renin-Angiotensin System Activation via Attenuation of Reactive Oxygen Species Generation

“…In diabetic rats, the AGT expression was increased, while the expressions of ACE and AT1 receptor were down-regulated. These changes were consistent with the previous study in vivo, including the data from clinical studies [27,43-45]. There is no clear answer for the different between in vitro and in vivo studies, but the inconsistency is not unique to RAS observation.…”

The ACE2-Angiotensin-(1–7)-Mas Axis Protects Against Pancreatic Cell Damage in Cell Culture

“…The expression of angiotensin II (AT) and the key component genes of RAS have identified the existence of local RAS in the pancreas. 30,31 The activation of RAS can induce pancreatic and peripheral microcirculation disturbances, which is an important mechanism leading to the development of SAP. The regulation of RAS in local tissues is affected by many factors, such as hormones, electrolyte changes, and stress.…”