Dopamine blockade attenuates the natriuresis of saline loading in the adrenalectomized rat.
Dopamine blockade with the dopamine-1/dopamine-2 antagonist cis-flupenthixol (CF) attenuates sodium excretion associated with saline loading in both innervated and denervated kidneys of the rat. Blockade of adrenal dopamine-2 receptors prevents the decrease in aldosterone secretion associated with saline loading and may also be responsible for the reduction in sodium excretion induced by CF. Therefore, to determine the role of adrenal dopamine-2 receptors in the attenuated natriuresis induced by CF, the effect of CF or vehicle treatment was examined in two groups of saline-loaded rats 80 (group I) and 120 min (group II) after adrenalectomy. In both groups, CF decreased glomerular filtration rate and sodium excretion after adrenalectomy. It is concluded that dopamine blockade attenuates the natriuresis associated with sodium loading by a direct effect in the kidney.
Jose
P A
PA
Department of Pediatrics, Georgetown University Medical Center, Washington, D.C.
Holloway
R R
RR
Campbell
T W
TW
Eisner
G M
GM
D000315:Adrenalectomy; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004231:Diuresis / Q000187:drug effects; D018492:Dopamine Antagonists; D005475:Flupenthixol / Q000494:pharmacology*; D006400:Hematocrit; D008297:Male; D009318:Natriuresis / Q000187:drug effects*; D011188:Potassium / Q000652:urine; D051381:Rats; D011921:Rats, Inbred WKY; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D012964:Sodium / Q000494:pharmacology; D013892:Thioxanthenes / Q000494:pharmacology*
D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; D013892:Thioxanthenes; D012964:Sodium; D005475:Flupenthixol; D011188:Potassium