Abstract P231: Offspring of Captopril Treated Spontaneously Hypertensive Rats Have Lower Angiotensin II Type 1 Receptor Expression Which is Associated With Lower Blood Pressure

Abstract

It has been reported that SHR rats receiving angiotensin converting enzyme (ACE) inhibitor Captopril decrease blood pressure (BP) in at least two generation after the treatment was stopped. A decreased response to an intracerebroventricular infusion angiotensin I and angiotensin II in treated animals and their offspring was reported; however there is no reported mechanism that explains the changes observed in the untreated offspring of the Captopril treated animals. We hypothesize that captopril reduces angiotensin II type 1 receptor (AT1R) expression in CNS of the offspring of SHR rats treated with captopril. Animal groups are as follows: control animals, captopril treated animals, offspring of the control animals, offspring of the treated animals where the mother was removed from the treatment immediately after giving birth and Offspring of treated animals where the mother was removed from the treatment at weaning. BP was measured by intra-arterial method and Tail cuff. AT1R expression was measured in brain tissue using the posterior wall of the forth ventricle, as well as the top half of the brain stem. BP was different between treated groups and their offspring vs. control (Table 1). AT1R expression was significantly reduced in both offspring groups of the treated animals, when compared to control (Table 1). Therefore we conclude that captopril reduces blood pressure in the offspring of captopril treated SHR rats and that associates with a decrease in AT1R expression in CNS. Further research is necessary to determine the possible epigenetic mechanisms involved in AT1R reduction.