Effect of nitric oxide synthase inhibition on postischemic cerebral hyperemia.
Publication/Presentation Date
7-1-1995
Abstract
We tested the hypothesis that inhibition of nitric oxide synthase (NOS) activity in brain before ischemia decreases postischemic hyperemia. Pentobarbital-anesthetized piglets underwent 15 min of complete global cerebral ischemia induced by elevation of intracranial pressure followed by 20 min of reperfusion. Before ischemia the animals were randomly assigned to receive either intravenous N omega-nitro-L-arginine methyl ester (L-NAME 10 mg/kg, n = 6, or 50 mg/kg, n = 6) or an equal volume of saline (10 ml, n = 8). Serial cerebral blood flow (radiolabeled microspheres) was measured at baseline and during ischemia and reperfusion. Forebrain postischemic hyperemia was documented after administration of saline (42 +/- 4 to 88 +/- 10 ml.min-1.100 g-1) and 10 mg/kg L-NAME (36 +/- 4 to 59 +/- 9 ml.min-1.100 g-1) but not after 50 mg/kg L-NAME (29 +/- 3 to 34 +/- 7 ml.min-1.100 g-1). However, the percent reduction in cerebral vascular resistance (CVR) fell during reperfusion to a similar extent in all three groups because of differences between groups in cerebral perfusion pressure changes during the protocol. CVR fell to the lowest level at 8 min of reperfusion in the saline-treated animals (2.0 +/- 0.16 to 0.68 +/- 0.05 mmHg.ml-1.min.100 g) compared with the L-NAME-treated animals (50 mg/kg: 4.0 +/- 0.3 to 1.8 +/- 0.2 mmHg.ml-1.min.100 g).(ABSTRACT TRUNCATED AT 250 WORDS)
Volume
269
Issue
1 Pt 2
First Page
341
Last Page
347
ISSN
0002-9513
Published In/Presented At
Greenberg, R. S., Helfaer, M. A., Kirsch, J. R., & Traystman, R. J. (1995). Effect of nitric oxide synthase inhibition on postischemic cerebral hyperemia. The American journal of physiology, 269(1 Pt 2), H341–H347. https://doi.org/10.1152/ajpheart.1995.269.1.H341
Disciplines
Medicine and Health Sciences | Pediatrics
PubMedID
7543258
Department(s)
Department of Pediatrics
Document Type
Article