Chronic experimental myocardial infarction produces antinatriuresis by a renal nerve-dependent mechanism
Braz. j. med. biol. res
;
37(2): 285-293, Feb. 2004. tab, graf
Artículo
en Inglés
| LILACS
| ID: lil-354170
ABSTRACT
The present study focused on the role of sympathetic renal nerve activity, in mediating congestive heart failure-induced sodium retention following experimental chronic myocardial infarction. Groups of male Wistar rats (240-260 g) were studied sham-operated coronary ligation (CON3W, N = 11), coronary ligation and sham-operated renal denervation (INF3W, N = 19), 3 weeks of coronary ligation and sympathetic renal nerve denervation (INF3WDX, N = 6), sham-operated coronary ligation (N = 7), and 16 weeks of coronary ligation (INF16W, N = 7). An acute experimental protocol was used in which the volume overload (VO; 5 percent of body weight) was applied for 30 min after the equilibration period of continuous iv infusion of saline. Compared to control levels, VO produced an increase (P < 0.01, ANOVA) in urine flow rate (UFR; 570 percent) and urinary sodium excretion (USE; 1117 percent) in CON3W. VO induced a smaller increase (P < 0.01) in USE (684 percent) in INF3W. A similar response was also observed in INF16W. In INF3WDX, VO produced an immediate and large increase (P < 0.01) in UFR (547 percent) and USE (1211 percent). Similarly, in INF3W VO increased (P < 0.01) UFR (394 percent) and USE (894 percent). Compared with INF3W, VO induced a higher (P < 0.01) USE in INF3WDX, whose values were similar to those for CON3W. These results suggest that renal sympathetic activity may be involved in sodium retention induced by congestive heart failure. This premise is supported by the observation that in bilaterally renal denervated INF3WDX rats myocardial infarction was unable to reduce volume expansion-induced natriuresis. However, the mechanism involved in urinary volume regulation seems to be insensitive to the factors that alter natriuresis.
Texto completo:
Disponible
Índice:
LILACS (Américas)
Asunto principal:
Sistema Nervioso Simpático
/
Riñón
/
Infarto del Miocardio
/
Natriuresis
Tipo de estudio:
Estudio pronóstico
Límite:
Animales
Idioma:
Inglés
Revista:
Braz. j. med. biol. res
Asunto de la revista:
Biologia
/
Medicina
Año:
2004
Tipo del documento:
Artículo
País de afiliación:
Brasil
Institución/País de afiliación:
Universidade Federal do Espírito Santo/BR
Similares
MEDLINE
...
LILACS
LIS