Effect of anesthesia on the expression of clock gene Clock and Bmal1 in New Zealand rabbits

To evaluate the effect of anesthetic drugs on the expression of circadian gene Clock and Bmal1 in the brain of New Zealand rabbits, and to explore their change pattern.

A total of 90 New Zealand rabbits were randomly divided into 5 groups (n=18 in each group): A normal saline group (1 mL/h saline, group S), a propofol group [600 µg/(kg·min^-1) propofol, 1 mL/h, group P], a 10% lipid group (1 mL/h lipid, group F), a dexmedetomidine group [1 µg/(kg·min^-1) dexmedetomidine, 1 mL/h, group D), a sevoflurane (SEV) group (2.5% SEV, SEV group). Inhaled and intravenous anesthetic drugs were stopped after 24 h. Experimental animals were killed at 0, 24, and 72 h after anesthesia, and their brain tissues were isolated. Western blotting was performed to measure the Clock and Bmal1 protein expression in the brain of rabbits.

At 0 and 24 h after anesthesia, compared with the group S, the levels of Clock and Bmal1 proteins were decreased significantly in the group P, the group D, and the group SEV (all P<0.05). At 72 h after anesthesia, compared with the group S, the levels of Clock and Bmal1 proteins showed no significant changes in the group P, the group D, and the SEV group (all P>0.05). Compared with the group S, the levels of Clock and Bmal1 proteins at all time points showed no significant changes in the group F (all P>0.05).

Anesthetic SEV, propofol, and dexmedetomidine can inhibit the expression of clock gene Clock and Bmal1 protein in the brain fissues of the New Zealand rabbits, and the suppression effect continues for at least 24 h after anesthesia, whereas the suppression decreases significantly at 72 h after anesthesia.