Objectives:The firing of action potentials after IJPs has been described as rebound excitation(off-response)which increases with an increase in the frequency and train duration of electrical field stimulation(EFS)of e...
详细信息
Objectives:The firing of action potentials after IJPs has been described as rebound excitation(off-response)which increases with an increase in the frequency and train duration of electrical field stimulation(EFS)of enteric ***-stimulus responses(during stimulation)including EJP,fast IJP and slow IJP have been well characterized in previous *** little is known about the mechanisms underlying off(post-stimulus)responses(PSR).In the present study,we will characterize the PSR in murine proximal and distal ***:C57/Bl6 mice were used for intracellular microelectrode recordings from the smooth muscle of the proximal and distal ***,L-NNA and MRS2500 were applied to investigate the responses to electrical field stimulation(EFS).Results:In the proximal colon,EFS evoked excitatory junction potentials(EJP)followed by fast and slow inhibitory junction potentials(IJP).Upon cessation of EFS,PSR showed slow depolarization with spike *** pretreatment did not affect PSR suggesting that PSR is not due to cholinergic ***2500 treatment inhibited fast IJP but had no effect on PSR.L-NNA inhibited slow IJP and significantly decreased *** the distal colon,EFS evoked mainly fast IJP with small amplitude of slow IJP.L-NNA treatment had minimum effect on slow IJP and negligible effect on ***,MRS2500significantly decreased fast IJP and almost abolished ***:The two regions of the colon display different EFS-induced on-responses and *** responses in the proximal colon and purinergic responses in the distal colon are main factor to evoke *** nitrergic IJP and purinergic IJP are mediated by ICC and PDGFRα+cells,respectively,the different regional responses may be due to the density of ICC or PDGFRα+cell in the proximal colon and distal colon.
暂无评论