Variations of vasoactive intestinal peptide (VIP) concentration in the lung of asthmatic patients

: The vasoactive intestinal peptide (VIP) concentrations in the pulmonary and systemic arterial blood were evaluated in 11 asthmatic patients in symptom-free period and during methacholin induced broncospasm. The basal venous and arterial mean values do not significantly differ. A significant difference was observed after bronchial challenge. This could be caused by an increased VIP pulmonary production as a defensive mechanism. No correlation was found between bronchial reactivity (as PD20-FEV1 Methacholin) and VIP concentrations.