NEUROPEPTIDE CONTENT OF LUNGS FROM ASTHMATIC AND NONASTHMATIC PATIENTS

Tracheal and lung parenchymal SP-LI (substance P-like immunoreactivity ) and VIP-LI (vasoactive intestinal peptide-like immunoreactivity) con tent was measured in HPLC-purified tissue extracts from patients with and without asthma. We detected significantly less SP-LI in tracheal t issue from asthmatic than from nonasthmatic patients, whereas parenchy mal SP-LI content was not significantly different between these groups . This finding does not support the concept that asthmatic lungs conta in excessive amounts of SP. Indeed, lower SP-LI content of tracheal ti ssues from asthmatic patients may reflect augmented SP release followe d by degradation. We detected greater quantities of VIP-LI in tracheal than in parenchymal tissue in both groups, but did not detect signifi cant differences in VIP-LI content in tracheal or parenchymal tissues from asthmatic and nonasthmatic patients. These findings indicate that asthmatic and nonasthmatic lungs contain similar levels of VIP.