Role of the Rostral VentrolateralMedulla in the Arterial Hypertension in Chronic Renal Failure

Adriana P. Castilho Dugaich,1 Elizabeth B. Oliveira-Sales,1 Nayda P. Abreu,
Mirian A. Boim,2 C´assia T. Bergamaschi,1 and Ruy R. Campos3 
 A component of chronic renal failure is high circulating angiotensin II and this leads to an increase in NAD(P)H oxidase , which is responsible for the production of superoxide. They wanted to quantify the subunits of NAD(P)H which are NADPH p47phox and gp91phox in CRF . They also looked at AT1 expression since Ang II is involved. In order to further investigate the role of oxidative stress and AT1 in hypertension in CRF, they injected tempol into the RVLM and the AT1 antagonist-candesartan. They also investigated glutamate and GABA sensitivity in CRF. mRNA expression for NADPHp47phox and gp91phox in the brainstem were greater in the CRF when compared to the control, however the expression of AT1 was down regulated in the CRF group. Tempol responses in rvlm were greater in the CRF and the control group actually had no response to tempol, further demonstrating that CRF leads to superoxide production in the RVLM. Responses to AT1 Ang II antagonist candesartan were not significantly different between groups. Glutamate responses were attenuated in the CRF group when compared to the control. GABA responses were greater in the CRF group compared to the control group. The data suggest that oxidative stress is contributing to the development of hypertension in CRF animals.