AIM: To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 (TRPM7) in the human gastrointestinal (GI) tract. METHODS: Conventional microel...AIM: To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 (TRPM7) in the human gastrointestinal (GI) tract. METHODS: Conventional microelectrode techniques were used to record intracellular electrical responses from human GI smooth muscle tissue. Immunohistochemistry was used to identify TRPM7 channels in interstitial cells of Cajat (ICCs). RESULTS: The human GI tract generated slow electrical waves and had ICCs which functioned as pacemak er cells. Flufenamic acid, a nonselective cation channel blocker, and 2-APB (2-aminoethoxydiphenyl borate) and La3+, TRPM7 channel blockers, inhibited the slowwaves. Also, TRPM7 channels were expressed in ICCs in human tissue. CONCLUSION: These results suggest that the human GI tract generates slow waves and that TRPM7 channels expressed in the ICCs may be involved in the gen- eration of the slow waves.展开更多
Canonical transient receptor potential 4(TRPC4) forms non-selective cation channels that contribute to phospholipase C-dependent Ca2+ entry into cells following stimulation of G protein coupled receptors and receptor ...Canonical transient receptor potential 4(TRPC4) forms non-selective cation channels that contribute to phospholipase C-dependent Ca2+ entry into cells following stimulation of G protein coupled receptors and receptor tyrosine kinases.Moreover,the channels are regulated by pertussis toxin-sensitive Gi/o proteins,lipids,and various other signaling mechanisms.TRPC4-containing channels participate in the regulation of a variety of physiological functions,including excitability of both gastrointestinal smooth muscles and brain neurons.This review is to present recent advances in the understanding of physiology and development of small molecular modulators of TRPC4 channels.展开更多
Intracellular Ca2+homeostasis is essential for vascular function and blood pressure regulation.Because of their unique roles in regulating intracellular Ca2+concentration and vascular function,a novel class of non-sel...Intracellular Ca2+homeostasis is essential for vascular function and blood pressure regulation.Because of their unique roles in regulating intracellular Ca2+concentration and vascular function,a novel class of non-selective cation channels,called transient receptor potential(TRP)channels,have emerged at the frontier of hypertension research.Based on their role in vasculature function regulation,TRP channels can be divided into two functional subtypes:one that participates in vasoconstriction and one that participates in vasodilatation.A functional imbalance of these two subtypes of TRP channels may disturb intracellular calcium([Ca2+]i)homeostasis,and the consequent vascular dysfunction may contribute to the development of hypertension.The potential of these TRP channels as novel pharmacological targets for the treatment of human hypertension is of great interest.展开更多
The optical guiding of a moderately intense laser pulse in a parabolic preformed plasma channel is analyzed by means of the variational method.Relativistic,ponderomotive and their coupling nonlinearities are included....The optical guiding of a moderately intense laser pulse in a parabolic preformed plasma channel is analyzed by means of the variational method.Relativistic,ponderomotive and their coupling nonlinearities are included.The conditions for periodic defocusing and focusing,as well as constant spot size propagation are given.It is found that the laser focusing is released by the coupling of relativistic and ponderomotive nonlinearities.展开更多
基金Supported by The Creative Research Initiative Center for Bio-Artificial Muscle of the Ministry of Education,Science and Technology (MEST) in Korea
文摘AIM: To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 (TRPM7) in the human gastrointestinal (GI) tract. METHODS: Conventional microelectrode techniques were used to record intracellular electrical responses from human GI smooth muscle tissue. Immunohistochemistry was used to identify TRPM7 channels in interstitial cells of Cajat (ICCs). RESULTS: The human GI tract generated slow electrical waves and had ICCs which functioned as pacemak er cells. Flufenamic acid, a nonselective cation channel blocker, and 2-APB (2-aminoethoxydiphenyl borate) and La3+, TRPM7 channel blockers, inhibited the slowwaves. Also, TRPM7 channels were expressed in ICCs in human tissue. CONCLUSION: These results suggest that the human GI tract generates slow waves and that TRPM7 channels expressed in the ICCs may be involved in the gen- eration of the slow waves.
基金supported in part by the National Natural Science Foundation of China(81228021)US National Institutes of Health(DK081654)
文摘Canonical transient receptor potential 4(TRPC4) forms non-selective cation channels that contribute to phospholipase C-dependent Ca2+ entry into cells following stimulation of G protein coupled receptors and receptor tyrosine kinases.Moreover,the channels are regulated by pertussis toxin-sensitive Gi/o proteins,lipids,and various other signaling mechanisms.TRPC4-containing channels participate in the regulation of a variety of physiological functions,including excitability of both gastrointestinal smooth muscles and brain neurons.This review is to present recent advances in the understanding of physiology and development of small molecular modulators of TRPC4 channels.
文摘Intracellular Ca2+homeostasis is essential for vascular function and blood pressure regulation.Because of their unique roles in regulating intracellular Ca2+concentration and vascular function,a novel class of non-selective cation channels,called transient receptor potential(TRP)channels,have emerged at the frontier of hypertension research.Based on their role in vasculature function regulation,TRP channels can be divided into two functional subtypes:one that participates in vasoconstriction and one that participates in vasodilatation.A functional imbalance of these two subtypes of TRP channels may disturb intracellular calcium([Ca2+]i)homeostasis,and the consequent vascular dysfunction may contribute to the development of hypertension.The potential of these TRP channels as novel pharmacological targets for the treatment of human hypertension is of great interest.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 11047152,11147005,and 11178002the Natural Science Foundation of Jiangxi Province under Grant No. 2010GQW0048
文摘The optical guiding of a moderately intense laser pulse in a parabolic preformed plasma channel is analyzed by means of the variational method.Relativistic,ponderomotive and their coupling nonlinearities are included.The conditions for periodic defocusing and focusing,as well as constant spot size propagation are given.It is found that the laser focusing is released by the coupling of relativistic and ponderomotive nonlinearities.