Angiotensin II inhibition increases diuresis during acute sympathetic activation in intact and denervated kidneys in rats with chronic myocardial infarction.
Heart Vessels
; 37(9): 1636-1646, 2022 Sep.
Article
em En
| MEDLINE
| ID: mdl-35689098
ABSTRACT
We examined urine excretion during primary acute sympathetic activation (PASA) in Wistar-Kyoto rats with myocardial infarction (MI). The rats underwent unilateral renal denervation (RDN) 7 weeks after coronary artery ligation. 4-10 days later, an acute experiment was performed under anesthetized conditions (n = 8 rats). Isolated carotid sinus pressure was changed stepwise from 60 to 180 mmHg, and the relationship between the arterial pressure (AP) and the normalized urine flow (nUF, urine flow normalized by the body weight) was examined. After obtaining the control data, an angiotensin II type 1 receptor blocker telmisartan (2.5 mg/kg) was intravenously administered. The effects of RDN, telmisartan, and heart weight (biventricular weight) on the relationship between AP and nUF were examined using multiple regression analyses. Regarding the slope of nUF versus AP (nUFslope), the constant term of the regression was positive (0.315 ± 0.069 µL·min-1·kg-1·mmHg-1), indicating that nUF increased with AP. The heart weight had a negative effect on nUFslope (P < 0.05), suggesting that the severity of MI was associated with the impairment of urine excretion. Telmisartan increased nUFslope by 0.358 ± 0.080 µL·min-1·kg-1·mmHg-1 (P < 0.001), whereas RDN had no significant effect on this parameter. The results indicate that unilateral RDN was unable to abolish the effect of the renin-angiotensin system on urine excretion during PASA. Circulating or locally produced angiotensin II, rather than ongoing renal sympathetic nerve activity, played a dominant role in the impairment of urine excretion during PASA in rats with chronic MI.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Angiotensina II
/
Infarto do Miocárdio
Limite:
Animals
Idioma:
En
Revista:
Heart Vessels
Assunto da revista:
CARDIOLOGIA
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Japão