Which of the following most correctly describes the sequence of toxic events that occur in brain during a stroke?
A) increased blood flow - activation of NA+/K+ transporters - membrane hyperpolarization - GABA release - excessive accumulation of extracellular CA++
B) reduced blood flow - inactivation of Na+/K+ transporters - membrane depolarization - glutamate release - excessive accumulation of intracellular CA++
C) reduced blood flow - activation of Na+/K+ transporters - membrane hyperpolarization - DA release - excessive accumulation of intracellular CL-
D) reduced blood flow - inactivation of Na+/K+ transporters - membrane hyperpolarization - GABA release - excessive accumulation of intracellular CA++
E) increased blood flow - reduced accumulation of extracellular CA++ - membrane hyperpolarization - GABA release

Question

Which of the following most correctly describes the sequence of toxic events that occur in brain during a stroke?
A) increased blood flow -> activation of NA+/K+ transporters -> membrane hyperpolarization -> GABA release -> excessive accumulation of extracellular CA++
B) reduced blood flow -> inactivation of Na+/K+ transporters -> membrane depolarization -> glutamate release -> excessive accumulation of intracellular CA++
C) reduced blood flow -> activation of Na+/K+ transporters -> membrane hyperpolarization -> DA release -> excessive accumulation of intracellular CL-
D) reduced blood flow -> inactivation of Na+/K+ transporters -> membrane hyperpolarization -> GABA release -> excessive accumulation of intracellular CA++
E) increased blood flow -> reduced accumulation of extracellular CA++ -> membrane hyperpolarization -> GABA release

Quizplus · Accepted Answer

During a stroke, there is reduced blood flow to the brain, which leads to inactivation of Na+/K+ transporters, membrane depolarization, and excessive release of glutamate. This excessive release of glutamate leads to the excessive accumulation of intracellular Ca++ and subsequent toxic events in the brain. Option A is incorrect as increased blood flow is not associated with stroke. Option C and D have incorrect descriptions of the events that occur during a stroke. Option E is also incorrect as increased blood flow is not associated with stroke.

Which of the Following Most Correctly Describes the Sequence of Toxic