title: Long-term exercise attenuates blood pressure responsiveness and modulates kidney angiotensin II signalling and urinary sodium excretion in SHR.
abstract: Observations have been made regarding the effects of long-term exercise training on blood pressure, renal sodium handling and renal renin-angiotensin-aldosterone (RAS) intracellular pathways in conscious, trained Okamoto-Aoki spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKy) normotensive rats, compared with appropriate age-matched sedentary SHR and WKy. To evaluate the influence of exercise training on renal function and RAS, receptors and intracellular angiotensin II (AngII) pathway compounds were used respectively, and lithium clearance and western blot methods were utilised. The current study demonstrated that increased blood pressure in SHR was blunted and significantly reduced by long-term swim training between the ages of 6 and 16 weeks. Additionally, the investigators observed an increased fractional urinary sodium excretion in trained SHR (SHR(T)) rats, compared with sedentary SHR (SHR(S)), despite a significantly decreased creatinine clearance (C(Cr)). Furthermore, immunoblotting analysis demonstrated a decreased expression of AT1(R) in the entire kidney of T(SHR) rats, compared with S(SHR). Conversely, the expression of the AT2(R), in both sedentary and trained SHR, was unchanged. The present study may indicate that, in the kidney, long-term exercise exerts a modulating effect on AngII receptor expression. In fact, the present study indicates an association of increasing natriuresis, reciprocal changes in renal AngII receptors and intracellular pathway proteins with the fall in blood pressure levels observed in T(SHR) rats compared with age-matched S(SHR) rats.
authors.affiliation: Departamento de Clínica Médica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, 13083-592 Campinas, São Paulo, Brazil.
authors.forename: Silmara
authors.initials: S
authors.lastname: Ciampone
authors.forename: Rafael
authors.initials: R
authors.lastname: Borges
authors.forename: Ize P
authors.initials: IP
authors.lastname: de Lima
authors.forename: Flávia F
authors.initials: FF
authors.lastname: Mesquita
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Cambiucci
authors.forename: José A R
authors.initials: JA
authors.lastname: Gontijo
mesh_terms: D000375:Aging / Q000187:drug effects; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D015153:Blotting, Western; D001835:Body Weight / Q000187:drug effects; D003404:Creatinine / Q000378:metabolism; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology; D007677:Kidney Function Tests; D008297:Male; D010805:Physical Conditioning, Animal; D051381:Rats; D011918:Rats, Inbred SHR; D011945:Receptors, Angiotensin / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects*; D012964:Sodium / Q000097:blood / Q000652:urine*; D013599:Systole / Q000187:drug effects; D013997:Time Factors
chemical_list: D011945:Receptors, Angiotensin; D000804:Angiotensin II; D012964:Sodium; D003404:Creatinine