Lower esophageal sphincter (LES) tone depends on PGF(2alpha) and thromboxane A(2) acting on receptors linked to G(i3) and G(q) to activate phospholipases and produce second messengers resulting in muscle contraction. We therefore examined PGF(2alpha) signal transduction in circular smooth muscle cells isolated by enzymatic digestion from cat esophagus (Eso) and LES. In Eso, PGF(2alpha)-induced ...

In response to inflammation, neutrophils deiminate histones and externalize chromatin. Neutrophil extracellular traps (NETs) are an innate immune defense mechanism, yet NETs also may aggravate chronic inflammatory and autoimmune disorders. Activation of peptidylarginine deiminase 4 (PAD4) is associated with NET release (NETosis) but the precise mechanisms of PAD4 regulation are unknown. We obse...

PURPOSE The purpose of this study was to determine the role of protein kinase C (PKC) in corneal endothelial cell proliferation. METHODS Immunocytochemistry and Western blotting were used to define the PKC isoforms expressed in primary cultures of rat corneal endothelial cells. For proliferation studies, primary cultures of rat corneal endothelial cells were serum-starved for 48 hours and inc...

The intracellular signaling of human urotensin II (hU-II) and its interaction with other vasoconstrictors such as ANG II are poorly understood. In endothelium-denuded rat aorta, coadministration of hU-II (1 nM) and ANG II (2 nM) exerted a significant contractile effect that was associated with increased protein kinase C (PKC) activity and phosphorylation of PKC-alpha/betaII and myosin light cha...

The present study investigated active tone development in isolated ring segments of rabbit epicardial coronary artery. Endothelium-denuded (E-) or endothelium-intact (E+) vessels treated with the NO synthase inhibitor N(omega)-nitro-L-arginine (100 microM) developed active tone, which was enhanced by stretch and reversed by the NO donor sodium nitroprusside (SNP; IC(50)=9 nM). Nifedipine abolis...

Protein kinase C (PKC) and mitogen-activated protein (MAP) kinases have been implicated in the modulation of agonist-induced contractions of large vessels. However, their role in pressure- and agonist-induced constrictions of skeletal muscle arterioles, which have a major role in regulating peripheral resistance, is not clearly elucidated. Thus constrictions of isolated rat gracilis muscle arte...

We have previously suggested that protein kinase C (PKC) contributes to persistent pain in the formalin test. This study compared the effects of pharmacological inhibition of PKC with either GF 109203X or chelerythrine on persistent pain following noxious chemical stimulation with its effects on mechanical hyperalgesia, which develops in the hindpaw contralateral to an injury produced by noxiou...

BACKGROUND Opioid preconditioning protects the myocardium against ischemia/reperfusion (IR) injury. By enhancing cardiomyocyte viability, opioids can enhance cardiac function and recovery from IR injury during acute cardiac care. The myocyte model HL-1 is an immortalized, mouse atrial cell line that expresses functional delta-opioid receptors. The HL-1 myocyte may be useful for IR injury resear...

A concise and efficient synthesis of benzo[c]phenanthridines was accomplished by the palladium-catalyzed ring-opening coupling of azabicyclic alkene with o-iodobenzoates, followed by tandem cyclization. The strategy was successfully applied in the total synthesis of benzo[c]phenanthridine alkaloids such as sanguinarine, chelerythrine, nitidine and avicine.