EFFECT OF VASOACTIVE INTESTINAL PEPTIDE (VIP) ON PROPRANOLOL-INDUCED BRONCHOCONSTRICTION

[摘要] There is now considerable evidence in favor of vasoactive intestinal peptide (VIP) as a neurotransmitter of nondrenergic noncholinergic nerves in the airways. The purpose of our study was to evaluate the influence of inhaled VIP on bronchomotor tone after a .beta.-adrenergic- and cholinergic-receptor blockage. The study was performed with six patients with asthma in 4 days. On the first day, a propranolol provocative dose producing a 20% change in FEV1 (PD20) was determined from the individual semilogarithmic dose-response curve. On the other days, the propranolol challenge was performed after inhalation of ipratropium bromide (40 .mu.g), VIP (70 .mu.g), and both drugs in randomized duble-blind order. Statistical analysis was performed by two-way analysis of variance. The results demonstrated that mean propranolol PD20 was 0.14 mg (geometric mean + SD = 1.22). Ipratropium bromide administration, like VIP administration, significantly raised the PD20 value. The administration of both drugs elicited a further remarkable increase of mean propranolol PD20. The results demonstrated that inhaled VIP influences bronchomotor tone and that this effect is independent of the cholinergic blockage.

[发布日期] 1988-10-01