Treinamento aeróbio (T) reduz o elevado RNAm de angiotensinogênio (AGT), no NTS de SHR. Este trabalho investiga a sequência temporal dos efeitos do T sobre a pressão arterial, freqüência cardíaca, RNAm e proteína de AGT e AT₁ no PVN, NTS e RVL. WKY e SHR, submetidos a T de baixa intensidade por 0, 1, 2, 4, 8 ou 12 semanas, tiveram a PA e FC basais registradas e após o sacrifício determinou-se o RNAm (RT-PCR) e imunofluorescência para AGT ou AT₁ e NeuN. SHR (vs WKY) apresentaram PA (174±2 vs 123±2 mmHg) e FC elevadas e maior RNAm de AT₁ no NTS(+67%). T reduziu a PA em S de T₄ à T₁₂ e FC em S em T₄ e WKY em T₈. Nos SHR, T reduziu o RNAm de AGT no PVN (-34% em T₂) e NTS (-30% em T₄), e de AT₁ apenas em T₁₂ (-56% e -39%, PVN e NTS). Nos WKY, T reduziu o RNAm de AGT(-49%) e AT₁(-58%) no RVL a partir de T₈. A imunofluorescência localizou estas proteínas, confirmando as alterações pelo T. Estes dados indicam que a queda de PA e FC são progressivas e mais precoces em SHR que em WKY e acompanhadas por redução de AGT no PVN e NTS dos S e redução de AGT e AT₁ no RVL dos WKY.

The aerobic training (T) for 12 weeks was effective in reducing the mRNA of angiotensinogen(AGT) in NTS of SHR. We evaluate in SHR and WKY time-course changes of T on blood pressure, heart rate, AGT and AT₁ mRNA and protein (PVN, NTS and RVL). WKY and SHR were T for 0,1,2,4,8 or 12 weeks, the baseline BP and HR were recorded and mRNA(RT-PCR) and Immunofluorescence for AGT, AT₁ and NeuN were made. SHR(vs. WKY) had high BP(174±2 vs 123±2 mmHg), HR and mRNA of AT₁ in the NTS(+67%). T reduced the BP only in SHR(-6.5% from T₄ to T₁₂) and HR in SHR in T₄ and WKY in T₈. In the SHR, T reduced the AGT mRNA within the PVN (-34% in T₂) and NTS (-30% in T₄), and AT₁ mRNA only in T₁₂ in PVN(-56%) and NTS(-39%). In WKY, T decreased of both AGT(-49%) and AT₁(-58%) mRNA in the RVL at T₈. Immunofluorescence localized these proteins, confirming the mRNA content changes induced by T. Our data indicate that the fall of BP and HR are progressive and appear earlier in SHR than in WKY and are accompanied by reduced AGT in the PVN and NTS of the SHR and reduced AGT and AT₁ in RVL of WKY.