title: Retention of cerebrovascular dilation after cortical spreading depression in anesthetized rabbits.
abstract: OBJECTIVE
  We examined responses of rabbit pial arterioles to three different stimuli before and after induction of cortical spreading depression.
  
  
  METHODS
  In urethane-anesthetized rabbits equipped with a closed cranial window, we measured pial arteriolar diameter during baseline conditions, topical application of calcitonin gene-related peptide (CGRP), topical application of acetylcholine, and inhalation of 10% CO2 in air (arterial hypercapnia) before cortical spreading depression and 30, 60, and 120 minutes after cortical spreading depression. Cortical spreading depression was induced by localized application of a 5% KCl solution anterior to the arteriole being measured.
  
  
  RESULTS
  Average baseline diameter was approximately 90 microns. During cortical spreading depression, arteriolar diameter increased to a peak value that was 50 +/- 4% above baseline (n = 32). Before cortical spreading depression, arteriolar diameter changed 47 +/- 7% (n = 9) during hypercapnia, 17 +/- 3% (n = 4) during 10(-9) mol/L CGRP, 42 +/- 10% (n = 7) during 10(-7) mol/L CGRP, 29 +/- 6% (n = 4) during 10(-6) mol/L acetylcholine, and 61 +/- 13% (n = 6) during 10(-4) mol/L acetylcholine. Arteriolar responsiveness to any of these stimuli was not changed significantly by prior cortical spreading depression.
  
  
  CONCLUSIONS
  Dilator capacity of pial arterioles is still intact in urethane-anesthetized rabbits after cortical spreading depression.
authors.affiliation: Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, NC 27157-1083.
authors.forename: D W
authors.initials: DW
authors.lastname: Busija
authors.forename: W
authors.initials: W
authors.lastname: Meng
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000768:Anesthesia, General; D000818:Animals; D001160:Arterioles / Q000187:drug effects / Q000502:physiology*; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology; D002245:Carbon Dioxide / Q000494:pharmacology; D002560:Cerebrovascular Circulation; D013181:Cortical Spreading Depression; D005260:Female; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology; D010841:Pia Mater / Q000098:blood supply*; D011817:Rabbits; D013997:Time Factors; D014664:Vasodilation / Q000187:drug effects
chemical_list: D002245:Carbon Dioxide; D015740:Calcitonin Gene-Related Peptide; D000109:Acetylcholine