Renal vasodilatation induced by DOI, a 5-HT₂ receptor agonist, in the canine kidney

An intrarenal infusion of (±)-l-(2,5-dimethoxy-4-iodophenyl)-2-arninopropane (DOI), a selective 5-HT₂ agonist, at a rate of 5 μg/min in anesthetized dogs resulted in an increase in renal blood flow (RBF) without any transient decrease as usually observed during the infusion of S-HT. During the infusion, urine flow (UF) and urinary sodium excretion rates (U_NAV) increased along with RBF while the mean arterial pressure and glomerular filtration rate did not change. After pretreatment with ritanserin, a selective S-HT₂ antagonist, DOI failed to increase RBF, UF and U_NA V. It is concluded that DOI produces renal vasodilatation mediated via 5-HT₂ receptors and has a diuretic action. DOI (1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane); 5-HT₂ receptors; Renal vasodilatation; Diuretic action.