Cytochrome oxidase is decreased in piglet hippocampus following hypoxia-ischemia.
We assessed cytochrome oxidase (CytOx) staining in sham-operated control piglets and in piglets subjected to 30 minutes of cerebral hypoxia-ischemia (H-I) plus 4 hours of reperfusion (REP). The 1-day-old piglets were sedated, anesthetized, and ventilated. Cerebral blood flows (CBFs) were quantitated using microspheres. H-I was induced by a combination of phlebotomy and cervical tourniquet; the brain was reperfused for four hours after 30 minutes of H-I. CBF was reduced during ischemia in experimental animals from 42 + 13 to 12 + 5 ml/min/100g. CytOx staining of hippocampal sections from 3 control and 3 experimental animals was compared. The staining of the stratum pyramidale neurons of the same portion of the CA1 sector in a single high power field was assessed in a blinded fashion in 4 corresponding sections from each animal, and graded from 0 = no staining to 3 = heavy staining. The results were compared using one-way analysis of variance. Cells with grade 3 staining were significantly more numerous in controls compared to H-I/REP animals (p = 0.03). There were significantly more cells with no CytOx staining in the experimental animals (p = 0.01). These findings suggest that CytOx staining in newborn piglet CA1 is a reliable method of assessing cell dysfunction after H-I.
Anderson
A
A
Dept. of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
Oviedo
M
M
Adcock
L M
LM
Yamashita
Y
Y
Louis
P T
PT
Goddard-Finegold
J
J
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D002545:Brain Ischemia / Q000201:enzymology* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D003576:Electron Transport Complex IV / Q000378:metabolism*; D006624:Hippocampus / Q000201:enzymology*; D006651:Histocytochemistry; D002534:Hypoxia, Brain / Q000201:enzymology* / Q000503:physiopathology; D008863:Microspheres; D015427:Reperfusion Injury / Q000201:enzymology; D013552:Swine
D003576:Electron Transport Complex IV