Localization of cholinergic nerves in lower airways of guinea pigs using antisera to choline acetyltransferase.

Primary antiserum to choline acetyltransferase (ChAT), a specific marker for cholinergic nerves, was used to characterize the distribution of cholinergic nerve fibers and nerve cell bodies in guinea pig airways. ChAT immunoreactive nerve fibers were localized to the smooth muscle throughout the conducting airways and in the lamina propria of the trachea and large bronchi. Likewise, all nerve cell bodies in the ganglia intrinsic to the trachea and bronchi displayed a cholinergic phenotype.

Role of soluble guanylyl cyclase in the relaxations to a nitric oxide donor and to nonadrenergic nerve stimulation in guinea pig trachea and human bronchus.

The effect of the novel, selective, soluble guanylyl cyclase inhibitor 1 H-[1,2,4]oxadiazolol[4,3-a]quinoxalin-1-one (ODQ) on the nitric oxide component of the nonadrenergic, noncholinergic relaxation in guinea pig trachea was examined. Relaxant responses to field stimulation (1-16 Hz, 8 V, 1 ms for 15 s) in the presence of indomethacin (3 microM), atropine (1 microM), propranolol (1 microM), alpha-chymotrypsin (2 U/ml) and histamine (3 microM) were partially inhibited by 0.1 microM ODQ and almost abolished by 1 microM ODQ.

Tachykinin-independent effects of capsaicin on smooth muscle in human isolated bronchi.

Contractile and relaxant responses to capsaicin and resiniferatoxin were examined in human isolated bronchus (5-12 mm o.d.).

An immunoglobulin E-dependent recombinant histamine-releasing factor induces interleukin-4 secretion from human basophils.

A novel recombinant histamine-releasing factor (rHFR), which stimulates secretion from a subpopulation of human basophils that express a particular type of immunoglobulin E (IgE) or IgE+, was found to induce interleukin-4 (IL-4) production from cells isolated from these same donors. The secretion of IL-4 protein induced by rHRF significantly correlated with histamine release and the amount of protein generated, and the kinetics were identical to those caused by anti-IgE activation. Furthermore, the ability of rHRF to induce IL-4 protein production from cells not normally responsive to this protein was transferred by passive sensitization with plasma containing IgE+ antibody.

Effects of CPAP on venous return.

Continuous positive airway pressure, like positive end-expiratory pressure (PEEP), increases lung volume and pleural pressure and usually decreases venous return. The decrease in venous return has been ascribed to a simple increase in right atrial pressure. However, recent studies have demonstrated PEEP also changes the resistive and elastic properties of peripheral veins.