OBJECTIVE: To determine the role of membrane potential and intracellular @entity460 kinetic changes in producing @entity455 during severe @entity548 . METHODS: @entity35 were subjected to @entity548 ( @entity548 ) for 2 hours. The spinotrapezius muscle was prepared for microscopy and the responses of arterioles in the muscle to @entity1063 (NE) were tested. The resting membrane potentials of isolated arterial strips were measured with a microelectrode. Membrane potential and intracellular @entity141 ([ @entity141 ]i) changes in isolated arteriolar smooth muscle cells (ASMCs) were determined with fluorescent probes and a confocal microscopy. RESULTS: The arteriolar resting membrane potential was decreased from -36.7 +/- 6.3 mV in control to -29.2 +/- 5.3 mV concurrent with the increase of vasoreactivity to NE at 20 minutes after @entity548 . At 120 minutes post- @entity548 , the resting potential hyperpolarized to -51.9 +/- 9.1 mV, and NE stimulated [ @entity141 ]i increase was reduced to 50% of the control values during the appearance of arteriolar hyporeactivity, i.e. the NE threshold of the arteriolar response increased 15 fold 2 hours after the onset of @entity548 as compared with normal animals. The state of vasoreactivity was closely related to the resting potential of vascular smooth muscle in @entity548 , with a correlation coefficient of 0.96. Treatment with @entity5217 , a selective blocker of @entity855 -sensitive K+ (KATP) channels, decreased the resting potential, increased NE-stimulated [ @entity141 ]i increase, and partially restored vasoreactivity in severe @entity548 . CONCLUSION: The results suggested that membrane hyperpolarization and the reduction of NE-stimulated [ @entity141 ]i increase in smooth muscle cells appeared to contribute to the @entity455 in @entity548 . The mechanism is likely to involve in KATP channels.

The role of membrane potential and @entity460 kinetic changes in the pathogenesis of XXXX during severe shock.

@entity455 :: ('MESH:D014652', 'Disease') :: ['vascular hyporeactivity'] @entity548 :: ('MESH:D006470', 'Disease') :: ['hemorrhage', 'hemorrhagic shock', 'HS'] @entity141 :: ('CHEBI:29108', 'Chemical') :: ['Ca2+'] @entity5217 :: ('MESH:D005905', 'Chemical') :: ['glybenclamide'] @entity460 :: ('MESH:D002118', 'Chemical') :: ['calcium'] @entity35 :: ('10116', 'Species') :: ['Rats'] @entity1063 :: ('MESH:D009638', 'Chemical') :: ['norepinephrine'] @entity855 :: ('MESH:D000255', 'Chemical') :: ['ATP']
@entity455 :: (MESH:D014652,Disease) :: ['vascular hyporeactivity']
