Hemodynamic effects on hepatic blood flow of a selective beta 2-adrenoceptor agonist, clenbuterol, in rat.
Acute clenbuterol administration (50 micrograms/kg, i.v.) to anesthetized normotensive rats, produce a marked reduction in the mean blood pressure, (MBP), about 58 mm Hg. Indocyanine Green clearance analysis (control, 1.83 +/- 0.15: clenbuterol, 1.10 +/- 0.20 ml/min/100 g, P < 0.05) showed that the action in the hepatic vascular bed is opposite to its systemic vasodilator effects. The hepatic blood flow (HBF) appears significantly reduced (control, 8.24 +/- 0.35: clenbuterol, 3.83 +/- 0.71 ml/min/100 g, P < 0.05) whereas the hepatic uptake and excretion proceedings were apparently not affected (control hepatic extraction coefficient, 0.225 +/- 0.024: clenbuterol, 0.300 +/- 0.04, NS). These findings show that a marked reduction in HBF follows systemic vasodilator effects produced by clenbuterol.
Masnatta
L D
LD
Department of Biopharmacy and Bioavailability, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Argentina.
Rubio
M C
MC
D000818:Animals; D001810:Blood Volume / Q000187:drug effects; D002976:Clenbuterol / Q000494:pharmacology*; D008102:Liver Circulation / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar
D002976:Clenbuterol