Effects of indomethacin on brain blood flow, cerebral metabolism
and sagittal sinus prostanoids after hypoxia in newborn piglets.
Coyle, Mara C., William Oh, Katherine H. Petersson, Barbara S.
Stonestreet.
BROWN UNIVERSITY SCHOOL OF MEDICINE, DEPARTMENT OF PEDIATRICS,
WOMEN & INFANTS' HOSPITAL OF RHODE ISLAND, PROVIDENCE, RHODE
ISLAND 02905
APStracts 2:0179H, 1995.
We tested the hypotheses that during recovery from hypoxia, newborn
piglets exhibit a post hypoxic cerebral hyperemia, indomethacin
pretreated piglets a post hypoxic cerebral hypoperfusion, and that
the changes caused by indomethacin are dose-dependent and related to
the loss of prostanoids. We studied piglets exposed to 40 minutes of
hypoxia after pretreatment with high (5 mg_Kg-1, n=9) or low (0.3
mg_Kg-1, n=8) dose indomethacin or placebo (n=9), and allowed to
recover for 120 minutes. In the placebo and low dose pretreated
groups, total and regional brain blood flow increased during hypoxia,
but returned to baseline 10 minutes after hypoxia. High dose
indomethacin pretreatment was associated with a post hypoxic
hypoperfusion to certain brain regions at 10 minutes of recovery to
values similar to that after indomethacin treatment before the onset
of hypoxia. During and after hypoxia, the cerebral metabolic rate of
oxygen (CMR02) was preserved in both the placebo and low dose groups,
and decreased significantly during hypoxia in the high dose group.
Sagittal sinus prostacyclin was reduced significantly in both
indomethacin treated groups throughout the study. We conclude that a
post hypoxic hyperemia is not observed in newborn piglets. This
finding was not altered by pretreatment with a therapeutic dose of
indomethacin, whereas, a pharmacologic dose was associated with
selective hypoperfusion to certain brain regions both before hypoxia
and during recovery from hypoxia.
Received 11 November 1995; accepted in final form 24 April 1995.
APS Manuscript Number H26-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 9 May 1995.