Different effect of serotonin on intracellular calcium ion dynamics in the smooth muscle cells between rat posterior ciliary artery and vorticose vein.

5-hydroxytriptamine (5-HT: serotonin) is an important transmitter that causes vessel constriction, although few studies have examined the effect of 5-HT on venous smooth muscles. The intracellular Ca(2+) concentration ([Ca(2+)]i) plays an essential role in stimulus-response coupling in numerous tissue/cells including vascular smooth muscle cells. The present study was performed to examine whether differences between arteries and veins in the response to 5-HT can be detected under confocal microscope with respect to [Ca(2+)]i dynamics.

Proton magnetic resonance spectroscopy and diffusion-weighted imaging of tumefactive demyelinating plaque.

Proton magnetic resonance spectroscopy, diffusion-weighted axonography, and diffusion tensor tractography in a patient with tumefactive demyelination plaque (TDP) were evaluated for differential diagnosis from glioblastoma. The findings of glutamate and glutamine elevations on magnetic resonance spectroscopy and apparent tracts within the lesion on axonography and tractography were unlikely to represent glioblastoma, and were thus useful for the preoperative diagnosis of TDP.

Regional differences in 5-HT receptors in cerebral and testicular arterioles of the rat as revealed by Ca2+ imaging of real-time confocal microscopy: variances by artery size and organ specificity.

5-hydroxytriptamine (5-HT) is an important transmitter for vessel constriction. The present study was performed to clarify the effect of 5-HT on smooth muscles in large- and small-sized cerebral and testicular arterioles by confocal microscopy, with special reference to intracellular Ca2+ concentration ([Ca2+]i) dynamics. In cerebral vessels, 5-HT induced a [Ca2+]i increase and the contraction of smooth muscle cells in large- and midsized arterioles (external diameters>50 microm) but not in small-sized arterioles.

Microtubule remodeling mediates the inhibition of store-operated calcium entry (SOCE) during mitosis in COS-7 cells.

Regulation of the intracellular calcium ion concentration ([Ca(2+)](i)) is critical, because calcium signaling controls diverse and vital cellular processes such as secretion, proliferation, division, gene transcription, and apoptosis. Store-operated calcium entry (SOCE) is the main mechanism through which non-excitable cells replenish and thus maintain this delicate balance. There is limited evidence which indicates that SOCE may be inhibited during mitosis, and the mechanisms leading to the presumed inhibition has not been elucidated.

Immunohistochemical localization of protease-activated receptors in cerebral and testicular arterioles of rats: their dependence on arteriole size and organ-specificity.

Protease-activated receptors (PARs) expressed in the endothelia and smooth muscles of vessels may play important roles in blood vessel function. Using intracellular calcium ion concentration ([Ca2+]i) imaging, we recently observed that small - but not large - arterioles of the brain responded to proteases, while testicular arterioles showed no response. The purpose of the present study was to examine the heterogeneity of the localization of PARs in arterioles using immunohistochemistry.