Early regional response of apoptotic activity in newborn piglet brain following hypoxia and ischemia.
Responses of selected neuroregulatory proteins that promote (Caspase 3 and Bax) or inhibit (Bcl-2, high Bcl-2/Bax ratio) apoptotic cell death were measured in the brain of piglets subjected to precisely controlled hypoxic and ischemic insults: 1 h hypoxia (decreasing FiO₂ from 21 to 6%) or ischemia (ligation of carotid arteries and hemorrhage), followed by 0, 2 and 4 h recovery with 21% FiO₂. Protein expression was measured in cortex, hippocampus and striatum by Western blot. There were no significant differences in expression of Caspase-3 between sham operated, hypoxic and ischemic groups. There were significant regional differences in expression of Bcl-2 and Bax in response to hypoxia and ischemia. The changes in Bcl-2/Bax ratio were similar for hypoxia and ischemia except for striatum at zero time recovery, with ischemia giving lower ratios than hypoxia. The Bcl-2/Bax ratio was also lower for the striatum than for the other regions of the brain, suggesting this region is the more susceptible to apoptotic injury.
Pirzadeh
A
A
Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
Mammen
A
A
Kubin
J
J
Reade
E
E
Liu
H
H
Mendoza
A
A
Greeley
W J
WJ
Wilson
D F
DF
Pastuszko
A
A
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism; D002545:Brain Ischemia / Q000378:metabolism / Q000503:physiopathology*; D053148:Caspase 3 / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D002534:Hypoxia, Brain / Q000378:metabolism / Q000503:physiopathology*; D010100:Oxygen / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D013552:Swine; D051028:bcl-2-Associated X Protein / Q000378:metabolism
D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D053148:Caspase 3; D010100:Oxygen