Vasoactive Intestinal Polypeptide (VIP) の気管支拡張作用ならびにその発生機序に関する研究

抄録

We studied the ability of vasoactive intestinal polypeptide to prevent or reduce bronchoconstriction caused by histamine or by prostaglandin F_2α (PGF_2α) and compared this ability to that of isoproterenol in the anesthetized dogs. The mechanism of bronchodilator action of VIP was also examined.
1) The protective effect of VIP aerosol on histmaine-or FGF_2α-induced bronchoconstriction was maximal after one hour and partial protection lasted at least three hours. This protective effect was greater than that of isoproterenol at one and two hours.
2) No significant change was noticed in systemic arterial blood pressure or heart rate after inhalation of VIP in doses of up to 5.0μg/kg.
3) Bronchodilator potency of VIP was not affected by bilateral vagotomy and β-adrenergic blockade.
4) VIP increased cyclic AMP in isolated guinea pig trachea.
The above results indicate that VIP represents a new class of potent bronchodilator agents, when administered by aerosol.