Aldosterone induces contraction of the resistance arteries in man.
Very rapid nongenomic effects of aldosterone in vitro have been described in recent years and in vivo evidence has been reported as well. In the present study, we investigated the rapid effect of aldosterone on resistance arteries in vivo in man. We performed a randomized, placebo-controlled, double-blind crossover study on ten healthy male volunteers. Forearm blood flow (FBF) was measured using venous occlusion plethysmography in both forearms. FBF was reduced by administration of aldosterone 2.5 pmol/min at min 4 (from 4.45+/-0.03 to 3.3+/-0.25 ml/100 ml tissue) and reached its nadir at min 12 (from 4.45+/-0.03 to 1.6+/-0.08 ml/100 ml tissue, P<0.001). Our study documents a direct nongenomic effect of aldosterone on the resistance arteries in vivo in man. The rapid vasoconstrictive effect of aldosterone at physiological concentrations opens the way to investigations on the vascular role of this steroid in several disorders, such as hypertension, characterized by elevated peripheral vascular resistance.
Romagni
Paola
P
Dipartimento di Fisiopatologia Medica, V Clinica Medica, Policlinico Umberto I, Facoltà di Medicina, Università di Roma La Sapienza, Viale del Policlinico, 00161 Rome, Italy.
Rossi
Fabio
F
Guerrini
Lara
L
Quirini
Chiara
C
Santiemma
Vittorio
V
D000328:Adult; D000450:Aldosterone / Q000008:administration & dosage*; D001795:Blood Pressure Determination; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005542:Forearm / Q000098:blood supply*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D010991:Plethysmography / Q000379:methods; D011336:Probability; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects; D012680:Sensitivity and Specificity; D014655:Vascular Resistance / Q000187:drug effects*; D014661:Vasoconstriction / Q000187:drug effects
D000450:Aldosterone