P-210: Beta-blockade with nebivolol enhances the acetylcholine-induced vasodilation in the cutaneaous vascular bed of normotensive volunteers

This study was undertaken to assess whether the beta1-adrenoceptor blocker nebivolol(N) increases the vasodilatory response to acetylcholine(Ach) when administered orally to healthy subjects. To this end 12 volunteers were randomly allocated to a 8-day treatment with nebivolol (n), 5 mg once a day, and atenolol(A),50 mg once a day, according to a cross-over design, with a 1 week wash-out period between the two treatment phases. The forearm skin blood flow(SBF) response to Ach applied by iontophoresis was determined using a laser-Doppler scanner imaging system before(T0) and 3 hours(T3) after N or A dosing, both on the first (Day 1) and the last day (Day 8) of treatment. The following Table shows the responses of SBF (perfusion units) (means±SD; *p