Spindle-shaped constriction and propagated dilation of arterioles during cortical spreading depression.
A dual illumination technique was used to examine the behavior of parenchymal arterioles of the cortex during cortical spreading depression in six cats. K+ produced a wave-ring spread of optical density changes concentrically from the injection site. At locations where the wave was passing, arterioles first constricted at one or two spots (55+/-43% of control), forming a spindle-shape in the early phase of cortical spreading depression, and then markedly dilated (155+/-57% of control) within 1 min. The dilation started at the constricted spots, propagated bidirectionally and finally resulted in full-length dilation of the arteriole. Although it varied in magnitude and time-course, this arteriolar behavior was observed in all six cats. Despite these changes, no associated downstream tissue microvascular flow changes were discernable.
Osada
Takashi
T
Department of Neurology, School of Medicine, Keio University, Shinjuku-ku, Tokyo, Japan.
Tomita
Minoru
M
Suzuki
Norihiro
N
D000818:Animals; D001160:Arterioles / Q000502:physiology*; D002415:Cats; D002540:Cerebral Cortex / Q000098:blood supply* / Q000187:drug effects / Q000502:physiology; D003250:Constriction; D013181:Cortical Spreading Depression / Q000187:drug effects / Q000502:physiology*; D005260:Female; D008297:Male; D011188:Potassium / Q000494:pharmacology; D013997:Time Factors; D014664:Vasodilation
D011188:Potassium