To observe the effects of transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia or controlled
hypotension on hippocampal neuronal damage and the inflammatory response in peripheral circulation and central nervous system
(CNS) after surgery, and to investigate its brain protection mechanism.Eighteen healthy male beagles aged 6 - 8 months were randomly divided into a general anesthesia group (group G), a controlled
hypotension group (group C) and a compound anesthesia acupuncture group (group A), 6 cases in each group. Dogs in group G
was anesthetized by isoflurane inhalation, and group C was combined with intravenous infusion of sodium nitroprusside based
on isoflurane inhalation to induce hypotension, and followed surgery after achieving the target blood pressure, and group
A was combined with TEAS at "Quchi" (LI 11), "Hegu" (LI 4) "Zu sanli" (ST 36) and "Sanyinjiao" (SP 6) based on controlled
hypotension, and then brain tissue was taken out on the 72 h after mean arterial pressure (MAP) was returned to baseline levels.
The concentration of IL-1beta,TNF-alpha in serum at different time points were detected by ELISA. The expression of IL-1beta,
TNF-alpha, Bcl-2, Bax and cleaved caspase-3 were measured by immunohistochemistry, and the apoptosis of hippocampus were detected
by TUNEL.(1) At different time points, the concentration of TNFalpha showed the trend of increase first and then decrease, while IL-1beta
concentration represented a trend of decrease first and then increase in both group C and group A, but there were no significant
differences in cytokine expression between the two groups (all P > 0.05). (2) The ratio of positive cells of IL-1beta, TNF-alpha
and caspase-3 in CA1 and CA3 of hippocampus in both group C and A were higher than those in group G (all P < 0.01), and cytokines
expression in group A were lower than those in group C (all P < 0.01), and caspase-3 in CA1 in group A was lower than that
in group C (P < 0.01). The ratio of Bcl-2/Bax in both group C and A were lower than that in group G (all P < 0.01), and that
in group A was higher than that in group C (P < 0.01 in CA1, P < 0.05 in CA3). (3) The apoptosis index (AI) of hippocampal
neurons in both group C and A was significantly higher than that in group G (P < 0.01), while AI in CA1 in group A was lower
than that in group C (P < 0.01).The TEAS can regulate the expression of inflammatory factor in hippocampus in animals undergoing general anesthesia or con
trolled hypotension surgery, further improving Bcl-2/Bax ratio, inhibiting the expression of caspase-3 and reducing neuron
apoptosis in hippocampus so as to play a neuroprotection.