The role of electrode size on the incidence of spreading depression and on cortical cerebral blood flow as measured by H2 clearance.

Published

Journal Article

Cerebral blood flow was measured by the H2 clearance method 30 and 60 min after the implantation of 300, 250, 125, or 50 microns diameter platinum-iridium electrodes 2 mm deep into the right parietal cortex of normothermic, normocarbic halothane-anesthetized rats. Another group of animals had 50 microns electrodes inserted 1 mm. In all animals, the presence or absence of a wave of spreading depression (SD) was noted at the time of implantation, with recordings made with glass micropipettes. H2 flow values were compared with those measured in gray matter from the same anatomical region (but from different rats), using [3H]nicotine. The incidence of SD ranged from 60% following insertion of 300 microns electrodes to 0% with 50 microns electrodes. H2 clearance flows also varied with electrode size, from 77 +/- 21 ml 100 g-1 min-1 (mean +/- standard deviation) with 300 microns electrodes to 110 +/- 31 and 111 +/- 16 ml 100 g-1 min-1 with 125 and 50 microns electrodes, respectively (insertion depth of 2 mm). A CBF value of 155 +/- 60 ml 100 g-1 min-1 was obtained with 50 micron electrodes inserted only 1 mm. Cortical gray matter blood flow measured with [3H]nicotine was 154 +/- 35 ml 100 g-1 min-1. When the role of SD in subsequent flow measurements was examined, there was a gradual increase in CBF between 30 and 60 min after electrode insertion in those animals with SD, while no such change was seen in rats without SD.(ABSTRACT TRUNCATED AT 250 WORDS)

Full Text

Duke Authors

Cited Authors

  • Verhaegen, MJ; Todd, MM; Warner, DS; James, B; Weeks, JB

Published Date

  • March 1992

Published In

Volume / Issue

  • 12 / 2

Start / End Page

  • 230 - 237

PubMed ID

  • 1548295

Pubmed Central ID

  • 1548295

International Standard Serial Number (ISSN)

  • 0271-678X

Digital Object Identifier (DOI)

  • 10.1038/jcbfm.1992.33

Language

  • eng

Conference Location

  • United States