Potassium-selective microelectrode revealed difference in threshold potassium concentration for cortical spreading depression in female and male rat brain
Abstrakt
It has been found with potassium-selective microelectrodes that the threshold extracellular concentration of potassium [K(+)](e) for eliciting fast spreading depression from the site of administration 1.5 mm away is 80% lower in the rat female cortex (8.0 +/- 0.6 mM) than in the male cortex (14.4 +/- 0.4 mM). The rate of the first slow phase of [K(+)](e) rise before reaching the threshold and speed of SD propagation were similar for both sexes as well as the rise of the second active fast phase of the [K(+)](e) increase.
Lower [K(+)](e) threshold in females can facilitate the rapid K(+) release from the nerve tissue cells that may cause a cerebrovascular vasodilatation and the attack of migraine pain. (C) 2010 Elsevier B.V. All rights reserved.