Novel form of spreading acidification and depression in the cerebellar cortex demonstrated by neutral red optical imaging.
A novel form of spreading acidification and depression in the rat cerebellar cortex was imaged in vivo using the pH-sensitive dye, Neutral red. Surface stimulation evoked an initial beam of increased fluorescence (i.e., decreased pH) that spread rostrally and caudally across the folium and into neighboring folia. A transient but marked suppression in the excitability of the parallel fiber-Purkinje cell circuitry accompanied the spread. Characteristics differentiating this phenomenon from the spreading depression of Leao include: high speed of propagation on the surface (average of 450 microm/s), stable extracellular DC potential, no change in blood vessel diameter, and repeatability at short intervals. This propagating acidification constitutes a previously unknown class of neuronal processing in the cerebellar cortex.
Chen
G
G
Department of Neurosurgery, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Hanson
C L
CL
Dunbar
R L
RL
Ebner
T J
TJ
D000143:Acids / Q000378:metabolism*; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002525:Cerebellar Cortex / Q000737:chemistry / Q000502:physiology*; D004396:Coloring Agents; D013181:Cortical Spreading Depression / Q000502:physiology*; D004558:Electric Stimulation; D005260:Female; D008297:Male; D009499:Neutral Red; D055095:Optics and Photonics; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D000143:Acids; D004396:Coloring Agents; D009499:Neutral Red; D011189:Potassium Chloride