Willmann Liang

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Contractions and relaxations of the urinary bladder occur in all directions to facilitate urine release and storage. Transverse and longitudinal contractility of detrusor smooth muscle have been studied before using various pharmacologic stimuli but not β agonists. Given the importance of β-adrenoceptors in mediating bladder relaxation, the effects of(More)
A rat model of ovariectomy-induced voiding dysfunction was established and the effects of ovariectomy and subsequent estrogen replacement on the affinity of muscarinic receptors in the rat bladder were determined. Voiding frequency and spatial distribution patterns were documented in sham-operated (control), and ovariectomized (placebo- or estrogen-treated)(More)
OBJECTIVES To examine the contractility of urothelium-intact (+UE) and urothelium-denuded (-UE) rat detrusor strips under adenosine triphosphate (ATP) treatment. Purinergic signaling exists in the bladder but both the inhibitory effect of ATP on detrusor contractions and the function of urothelial ATP are not established. METHODS Detrusor strips were(More)
Endothelial dysfunction often precedes Type 2 diabetes-associated cardiovascular complications. One important cause of endothelial dysfunction is oxidative stress, which can lead to reduced nitric oxide (NO) bioavailability. In this study, we examined the effects of ramipril (an angiotensin-converting enzyme inhibitor, ACEI) on reactive oxygen species (ROS)(More)
OBJECTIVES To investigate the effects of voltage-sensitive K(+) channel blockade on phasic contractions in transverse (TR) and longitudinal (LO) rat detrusor strips. The contractility of LO detrusor strips has been studied more extensively than that of TR ones, with the latter hardly used in experiments. Phasic contractions, regulated by various types of(More)
The roles played by K(+) channels in the urothelium (UE) and detrusor smooth muscle (DSM) in regulating agonist-induced bladder contraction is not known at present. Thus, the effects in carbachol (CCh)-induced contraction in UE-intact (+UE) and UE-denuded (-UE) rat detrusor strips pretreated with K(+)-channel blockers were investigated here. The(More)
In this study, we examined histamine-induced calcium signaling in cultured human valvular myofibroblasts (hVMFs), which are the most prominent interstitial cells in cardiac valves mediating valvular contraction, extracellular matrix secretion, and wound repair. Despite the functional importance of VMFs in cardiac valves, the cellular-signaling pathways,(More)
This teaching article uses the report by Kwan et al., "Effects of methacholine, thapsigargin, and La(3+) on plasmalemmal and intracellular Ca(2+) transport in lacrimal acinar cells," where the effects of Ca(2+)-mobilizing agents in regulating Ca(2+) fluxes were examined under various conditions. Upper-level undergraduate and new graduate students in(More)
Valvular myofibroblasts (VMFs) are present in large numbers in the cardiac valve. Although the functional roles of VMFs in vivo remain to be determined, evidence suggests the cells' ability to contract in vitro. Since Ca2+ is important in the contractility of many cell types, we examined Ca2+ responses induced by different agonists in normal and rheumatic(More)
In this study, we identified ryanodine receptors (RyRs) as a component of a cytosolic Ca(2+) removal pathway in freshly isolated rabbit aortic endothelial cells. In an earlier article, we reported that the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) and Na(+)/Ca(2+) exchanger (NCX) function in series to extrude cytosolic Ca(2+) to the extracellular(More)