[Effects of taurine on early changes of excitatory amino acids in rabbit brain due to deep hypothermic circulatory arrest].
OBJECTIVE
To study the effects of taurine (Tau) on early changes of excitatory amino acids (EAA) in hippocampus rabbit brain due to deep hypothermic circulatory arrest (DHCA).


METHODS
Sixteen New Zealand rabbits were randomly allocated into 2 groups: Tau 150 mg/kg group (group I, n = 8), control group (group II, n = 8). Cardiac pulmonary bypass (CPB) was set up after cerebral microdialysis model was established. High performance liquid chromatography was employed to monitor the continuous changes of glutamic acid (Glu), aspartic acid (Asp), Tau and glycine (Gly) in the hippocampus CA1 region at anaesthesia periods, CPB stage, pre 30 minutes in DHCA, post 30 minutes in DHCA, pre 30 minutes in rewarming, post 30 minutes in rewarming.


RESULTS
The increase of Glu in group II was (5.1 +/- 1.5) and (4.1 +/- 1.4) times higher than that at anaesthesia periods (t = 3.74, 5.45, P < 0.01), and the increase of Glu in group I was (2.1 +/- 1.5) and (1.1 +/- 0.4) times than that at anaesthesia periods at pre 30 minutes and post 30 minutes rewarming stage respectively. Rising of Gly in group II was 6.7 (3.6, 13.6) times than that at anaesthesia periods (T = 75.00, P < 0.05), the rising of Gly in group I was 4.2 (3.8, 11.5) times at post 30 minutes in DHCA. Rising of Tau in group I was 6.9 (3.0, 14.2) and 10.6 (2.8, 22.5) times than that at anaesthesia periods (T = 75.00, P < 0.05 and T = 90.00, P < 0.05) and rising of Tau in group II was 4.0 (3.0, 5.7) and 3.2 (1.2, 7.6) times than that at anaesthesia periods at post 30 minutes in DHCA and pre 30 minutes rewarming stage respectively. Asp was no evident change at every periods.


CONCLUSIONS
DHCA might increase the excitatory amino acids in the early phases of circulatory restoration. Exterior Tau 150 mg/kg could inhibit release of EAA.
Li
Ming
M
Department of Surgery, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China. Lee99720@sohu.com
Gao
Guo-dong
GD
Zheng
Jun
J
Sun
Li-zhong
LZ
Long
Cun
C
D000818:Animals; D002545:Brain Ischemia / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D004195:Disease Models, Animal; D018846:Excitatory Amino Acids / Q000378:metabolism*; D005112:Extracorporeal Circulation / Q000009:adverse effects* / Q000379:methods; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D007036:Hypothermia, Induced; D008297:Male; D011817:Rabbits; D013654:Taurine / Q000494:pharmacology*
D018846:Excitatory Amino Acids; D013654:Taurine