Neutrophil functions and autoimmune arthritis in the absence of p190RhoGAP: generation and analysis of a novel null mutation in mice.

Beta(2) integrins of neutrophils play a critical role in innate immune defense, but they also participate in tissue destruction during autoimmune inflammation. p190RhoGAP (ArhGAP35), a regulator of Rho family small GTPases, is required for integrin signal transduction in fibroblasts. Prior studies have also suggested a role for p190RhoGAP in beta(2) integrin signaling in neutrophils.

Role of Nox2 in elimination of microorganisms.

NADPH oxidase of the phagocytic cells (Nox2) transfers electrons from cytosolic NADPH to molecular oxygen in the extracellular or intraphagosomal space. The produced superoxide anion (O*2) provides the source for formation of all toxic oxygen derivatives, but continuous O*2 generation depends on adequate charge compensation. The vital role of Nox2 in efficient elimination of microorganisms is clearly indicated by human pathology as insufficient activity of the enzyme results in severe, recurrent bacterial infections, the typical symptoms of chronic granulomatous disease.

Consequences of the electrogenic function of the phagocytic NADPH oxidase.

NADPH oxidase of phagocytic cells transfers a single electron from intracellular NADPH to extracellular O2, producing superoxide (O.-2), the precursor to several other reactive oxygen species. The finding that a genetic defect of the enzyme causes chronic granulomatous disease (CGD), characterized by recurrent severe bacterial infections, linked O.

Angiotensin II type 1 (AT(1)) receptor blockade enhances the L-NAME-induced vasoconstriction in rat submandibular gland.

The vasoregulatory role of nitric oxide (NO) and angiotensin II type 1 (AT(1)) receptors in the circulation of the submandibular gland (SMG) of rats was studied. The glandular blood flow was determined by means of laser Doppler flowmetry and rubidium isotope technique. The data obtained by these two methods correlated well (r = 0.