Extracellular potassium and blood flow in the post-ischemic rat brain.
The concentration of extracellular potassium, [K+]e, was measured in parietal cortex and basal ganglia of rats during and after ten minutes of complete cerebral ischemia. The post-ischemic normalization of [K+]e was considerably delayed in parietal cortex compared to basal ganglia, but in both regions, [K+]e reached its normal concentration within 4 min of the end of the ischemia. Also, in both regions blood flow was elevated at the time of maximal [K+]e decrease. Our findings suggest that the normalization of [K+]e and cerebrovascular resistance after ischemia are related by positive feed-back, possibly via the stimulation of Na+-K+-ATPase.
D000818:Animals; D001479:Basal Ganglia / Q000378:metabolism*; D002540:Cerebral Cortex / Q000098:blood supply / Q000378:metabolism*; D005110:Extracellular Space / Q000378:metabolism*; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D008297:Male; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D012039:Regional Blood Flow; D014655:Vascular Resistance
D011188:Potassium