What is Dopamine, in renal doses, in shock leads to: March 2009 and explain in detail?
Ans. C: Dilatation of renal vasculature Dopamine at "renal dose"/ low dosage binds D-lreceptors and effects in dilating blood vessels, increasing blood flow to renal, mesenteric, and coronary aeries; and increasing overall renal perfusion. Dopamine therefore has a diuretic effect, potentially increasing urine output. Intermediate dosages have a positive inotropic and chronotropic effect through increased beta-1 activation. It is used in patients with shock or hea failure to increase cardiac output and blood pressure. High dose is the "pressor" dose. This dose causes vasoconstriction, increases systemic vascular resistance, and increases blood pressure through alpha-1 receptor activation; but can cause the vessels in the kidneys to constrict to the point where they will become non-functional