Object. The effects of ATP-introduced a rise in cytosolic free Ca2+ concentration and inhibition of nitric oxide were investigated. Method. Measurement of free Ca2+([Ca2+] i)of cultured rat tail arterial smooth muscle...Object. The effects of ATP-introduced a rise in cytosolic free Ca2+ concentration and inhibition of nitric oxide were investigated. Method. Measurement of free Ca2+([Ca2+] i)of cultured rat tail arterial smooth muscle cells using Fura-2/AM dual excitation wavelength spectrofluorometer. Results. There are two components of [Ca2+] i can be evoked by ATP. One part is Ca2+ entry from Ca2+ channel and formed a plateau. The another part is a peak that released from Ca2+ store. Both of them can be inhibited by NO. Conclusion. The ATP induced [Ca2+] i rise that release Ca2+ from both Insp 3 and ryanochine receptors and Ca2+ entry through calcium channels. The inhibition of NO on ATP induced [Ca2+] i rise that was mediated by cGMP.展开更多
There are at least eight kinds of different potassium channels on cardiac cell membrane.This paper presents a nonlinear property membrane outward current going rectifying potassium channel and the inhibitory effects o...There are at least eight kinds of different potassium channels on cardiac cell membrane.This paper presents a nonlinear property membrane outward current going rectifying potassium channel and the inhibitory effects of oxygen free radical on this channel.The current-voltage relation of this nonlinear-membrane can be defined by an equation I= 8a3/(0.01v2+ 4a2)2 and the maximum conductance of this channel is-75.3 PS.展开更多
Uging diet control method to feed the weaning male Wistar rats with selenium and iodine deficiency Keshan endemic area food for 8 weeks to set up animal model. Singal channel recortling in cell attached model was used...Uging diet control method to feed the weaning male Wistar rats with selenium and iodine deficiency Keshan endemic area food for 8 weeks to set up animal model. Singal channel recortling in cell attached model was used to measure cardiac cell membrane potassium channel conductances. which coincide with the cardiac cell membrane potassium channel conductances in normal Wistar rats.The potassium channel conductance on selenlum and lodine cleficiency rat cardiac cell membrane is showing current-voltage increasing lineally in the range of clamping volatge 0±30 mV with channel conductance of 43.4 pS. The channel current does not increase depending on the clamping voltage that is showing the rectifying characteristic and the channel current amplitude can be augmented by added KIOa 5 mmol/L in bath solution. A kind of inward rectiyfing potassium channel activity was recorded, but this channel activity disappeared affer lasting 6～ 10 minutes only. Then an inward rectifying potassium channel with the conductance of 11. 2 PS was activated by KIOa 5 mmol/L, introduced to bath solution. Both conductances are less than that of normal Wistar rats.展开更多
文摘Object. The effects of ATP-introduced a rise in cytosolic free Ca2+ concentration and inhibition of nitric oxide were investigated. Method. Measurement of free Ca2+([Ca2+] i)of cultured rat tail arterial smooth muscle cells using Fura-2/AM dual excitation wavelength spectrofluorometer. Results. There are two components of [Ca2+] i can be evoked by ATP. One part is Ca2+ entry from Ca2+ channel and formed a plateau. The another part is a peak that released from Ca2+ store. Both of them can be inhibited by NO. Conclusion. The ATP induced [Ca2+] i rise that release Ca2+ from both Insp 3 and ryanochine receptors and Ca2+ entry through calcium channels. The inhibition of NO on ATP induced [Ca2+] i rise that was mediated by cGMP.
文摘There are at least eight kinds of different potassium channels on cardiac cell membrane.This paper presents a nonlinear property membrane outward current going rectifying potassium channel and the inhibitory effects of oxygen free radical on this channel.The current-voltage relation of this nonlinear-membrane can be defined by an equation I= 8a3/(0.01v2+ 4a2)2 and the maximum conductance of this channel is-75.3 PS.
文摘Uging diet control method to feed the weaning male Wistar rats with selenium and iodine deficiency Keshan endemic area food for 8 weeks to set up animal model. Singal channel recortling in cell attached model was used to measure cardiac cell membrane potassium channel conductances. which coincide with the cardiac cell membrane potassium channel conductances in normal Wistar rats.The potassium channel conductance on selenlum and lodine cleficiency rat cardiac cell membrane is showing current-voltage increasing lineally in the range of clamping volatge 0±30 mV with channel conductance of 43.4 pS. The channel current does not increase depending on the clamping voltage that is showing the rectifying characteristic and the channel current amplitude can be augmented by added KIOa 5 mmol/L in bath solution. A kind of inward rectiyfing potassium channel activity was recorded, but this channel activity disappeared affer lasting 6～ 10 minutes only. Then an inward rectifying potassium channel with the conductance of 11. 2 PS was activated by KIOa 5 mmol/L, introduced to bath solution. Both conductances are less than that of normal Wistar rats.
