To elucidate the mechanism of cyclic nucleotides, such as adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5' -cyclic monophosphate (cGMP), in the regulation of human gastric motility, we examined the effects of forskolin (FSK), isoproterenol (ISO) and sodium nitroprusside (SNP) on the spontaneous, high K(+) and acetylcholine (ACh)-induced contractions of corporal circular smooth mu...

CONTRACTING GRANULATION TISSUES CONTAIN FIBROBLASTS THAT DEVELOP CHARACTERISTICS TYPICAL OF SMOOTH MUSCLE: (a) They contain an extensive cytoplasmic fibrillar system. (b) They show immunofluorescent labeling of their cytoplasm with human anti-smooth muscle serum. (c) The nuclei show complicated folds and indentations, indicative of cellular contraction. (d) There are cell-to-cell and cell-to-st...

Nitric oxide (NO) relaxes most smooth muscle, including the circular smooth muscle (CSM) of the esophagus, whereas in the adjacent longitudinal smooth muscle (LSM), it causes contraction. The second messenger pathways responsible for this NO-induced LSM contraction are unclear, given that these opposing effects of NO are both cGMP dependent. In intestinal LSM, but not CSM, cADP ribose (cADPR)-d...

1 contraction, but not via enhanced myosin light chain phosphorylation 2 3 Michael P. WALSH, Keith THORNBURY, William C. COLE, Gerard SERGEANT, Mark 4 HOLLYWOOD and Noel McHALE 5 6 Smooth Muscle Research Group and Department of Biochemistry and Molecular Biology, Faculty of 7 Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada, Smooth Muscle Research Centre, 8 Dundalk Institute of...

Coordinated gastrointestinal smooth muscle contraction is critical for proper nutrient absorption and is altered in a number of medical disorders. In this work, we demonstrate a critical role for the RGD-binding integrin α8β1 in promoting nutrient absorption through regulation of gastrointestinal motility. Smooth muscle-specific deletion and antibody blockade of α8 in mice result in enhanced ga...

Certain flavonoids inhibit antigen-induced release of histamine from mast cells and basophils and also inhibit contraction of guinea pig ileum induced by histamine, acetylcholine, and PGE2. We examined the effect of one flavonoid, quercetin, on anaphylactic smooth muscle contraction of ileum from guinea pigs sensitized to egg albumin. Quercetin inhibited both the phasic and tonic components of ...

Aortic smooth muscle contains limiting amounts of myosin light chain kinase (MLCK) for myosin regulatory light chain (RLC) phosphorylation and contraction that predisposes to thoracic aortic disease in humans containing heterozygous loss-of-function mutations in MYLK. We tested the hypothesis that thoracic aortic smooth muscle contraction may also be susceptible to variations in the smooth musc...

The aim of this study was to find out lead interaction on acetylcholine-induced ileal (0.8 "to 1" longitudinal total strips) contractions in varying calcium (Ca++) or magnesium (Mg++) media and the cholinergic mechanism. Potentiation of ileal strips by lead (Pb++) remained dose-dependent as elicited by acetylcholine-induced contractions (1.81 x 10(-6) M to 1.28 x 10(-4) M). These were completel...

In several clinical disorders, there are interactions between inflammation-dependent tissue injury and thrombin formation, fibrin deposition, and impaired fibrinolysis. New evidence generated from a mouse model of allergic airway hyperreactivity suggests that disordered coagulation and fibrinolysis may contribute to the pathogenesis of asthma. The inflammatory mechanisms that lead to airway smo...