Factors involved in the neuronal death during postischemic reperfusion: experimental study in rabbits.
OBJECTIVE
To explore the main pathogenic factors in the development of neuronal death during normothermic reperfusion in rabbits.


METHODS
Ninety-six New Zealand rabbits were randomly allocated into two groups: group I served as non-ischemic controls; group II served as postischemic normothermic reperfusion models. Complete cerebral ischemia was induced by the four-vessel model for 30 minutes. After ischemia, rabbits in group II were further divided into three subgroups according to the duration of reperfusion: subgroup A, 30 minutes; subgroup B, 180 minutes and subgroup C, 360 minutes. Twenty-eight biochemical parameters in the brain were measured, and neuronal changes were observed by histomorphological assessment. Neurons of 12 regions were differentiated into four types: type A (normal), type B (mildly damaged), type C (severely damaged) and type D (necrotic). Bivariate correlate analysis between the levels of biochemical parameters and the percentages of each type of neurons was carried out.


RESULTS
The main parameters involved in the progressive decrement of type A neurons were VIP, beta-EP, PGI2, T3, T4 and Na+, K(+)-ATPase; in the increment of type B were beta-EP and TXB2; in the increment of type C were GLU and TXB2/PGI2 respectively; in the stepwise increment of percentages of type D neurons were T4, Na+, K(+)-ATPase, GLU, T3 and VIP (P < 0.05).


CONCLUSIONS
The main factors involved in the development of neuronal death during postischemic normothermic reperfusion in rabbits include hypermetabolism, deactivation of Na+, K(+)-ATPase, release of excitatory amino acids and disorder of neuropeptides.
Duan
M
M
Department of Anesthesiology, Clinical School of Medical College of Nanjing University, Nanjing General Hospital of PLA, Nanjing 210002, China.
Li
D
D
Xu
J
J
Wang
G
G
Fu
S
S
D000818:Animals; D002545:Brain Ischemia; D016923:Cell Death; D005260:Female; D008297:Male; D009474:Neurons / Q000473:pathology; D011817:Rabbits; D011897:Random Allocation; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013929:Thromboxane B2 / Q000378:metabolism*; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism*; D001615:beta-Endorphin / Q000378:metabolism*
D014660:Vasoactive Intestinal Peptide; D013929:Thromboxane B2; D001615:beta-Endorphin; D000254:Sodium-Potassium-Exchanging ATPase