BACKGROUND: The present study aimed to characterize the effects of epinine, the active metabolite of ibopamine on tension development in human renal arteries. METHODS AND RESULTS: Experiments were performed on isolated human renal arteries rings obtained during surgery due to kidney tumors (n = 12). Epinine concentration-dependently relaxed isolated precontracted (PGF2 alpha) human renal artery rings (P < 0.05) in the presence of phentolamine, as effectively (epinine -30 +/- 4 mN, dopamine -31 +/- 5 mN) and with the same potency as dopamine (epinine EC50 0.7 mumol/l (0.4-1.2 mumol/l), dopamine 0.5 mumol/l (0.2-1.7 mumol/l). This effect was antagonized by the specific D1-receptor-antagonist SCH 23390. Effective beta-adrenoceptor antagonistic concentrations of propranolol did not affect epinine-induced vasorelaxation. In the absence of alpha- and beta-adrenoceptor-antagonists the potency of epinine to contract renal artery rings was significantly higher compared to dopamine indicating a higher affinity of epinine to alpha-adrenoceptors. CONCLUSION: The present study provides evidence for direct vasodilatory effects of epinine via activation of D1-receptors on human renal arteries.
BACKGROUND: The present study aimed to characterize the effects of epinine, the active metabolite of ibopamine on tension development in human renal arteries. METHODS AND RESULTS: Experiments were performed on isolated human renal arteries rings obtained during surgery due to kidney tumors (n = 12). Epinine concentration-dependently relaxed isolated precontracted (PGF2 alpha) human renal artery rings (P < 0.05) in the presence of phentolamine, as effectively (epinine -30 +/- 4 mN, dopamine -31 +/- 5 mN) and with the same potency as dopamine (epinine EC50 0.7 mumol/l (0.4-1.2 mumol/l), dopamine 0.5 mumol/l (0.2-1.7 mumol/l). This effect was antagonized by the specific D1-receptor-antagonist SCH 23390. Effective beta-adrenoceptor antagonistic concentrations of propranolol did not affect epinine-induced vasorelaxation. In the absence of alpha- and beta-adrenoceptor-antagonists the potency of epinine to contract renal artery rings was significantly higher compared to dopamine indicating a higher affinity of epinine to alpha-adrenoceptors. CONCLUSION: The present study provides evidence for direct vasodilatory effects of epinine via activation of D1-receptors on human renal arteries.
Authors: J D Port; E M Gilbert; P Larrabee; P Mealey; K Volkman; R Ginsburg; R E Hershberger; J Murray; M R Bristow Journal: Circulation Date: 1990-03 Impact factor: 29.690
Authors: M R Bristow; R Ginsburg; W Minobe; R S Cubicciotti; W S Sageman; K Lurie; M E Billingham; D C Harrison; E B Stinson Journal: N Engl J Med Date: 1982-07-22 Impact factor: 91.245
Authors: D J van Veldhuisen; A J Man in 't Veld; P H Dunselman; D J Lok; H J Dohmen; J C Poortermans; A J Withagen; W H Pasteuning; J Brouwer; K I Lie Journal: J Am Coll Cardiol Date: 1993-11-15 Impact factor: 24.094