To investigate the effect of Shenfu injection preconditioning on ventilator-induced brain injury in rats.

Sixty healthy adult male Sprague-Dawley rats, weighing 300-320 g, were divided into 3 groups (n=20 each) using a random number table: control group (group C), ventilator-induced brain injury group (group VIBI) and Shenfu injection group (group SF). Rats were mechanically ventilated for 6 h with tidal volume of 40 ml/kg in VIBI and SF groups.Rats were mechanically ventilated for 6 h with tidal volume of 10 ml/kg in group C. Shenfu injection 20 ml/kg was injected intraperitoneally at 30 min before ventilation in group SF.Blood samples were collected at 2 and 6 h of ventilation for measurement of the concentrations of serum S100β protein (by enzyme-linked immunosorbent assay). Then the rats were sacrificed at the end of ventilation, and brains were removed for determination of the contents of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) (by enzyme-linked immunosorbent assay) and expression of glutamate decarboxylase (GAD) and γ-aminobutyric acid type A (GABA_A) receptor in brain tissues (by Western blot).

Compared with group C, the serum concentrations of S100β protein at each time point of ventilation and contents of IL-1β and TNF-α in brain tissues were significantly increased, and the expression of GAD and GABA_A receptor was down-regulated in VIBI and SF groups (P<0.05). Compared with group VIBI, the serum concentrations of S100β protein at each time point of ventilation and contents of IL-1β and TNF-α in brain tissues were significantly decreased, and the expression of GAD and GABA_A receptor was up-regulated in group SF (P<0.05).

Shenfu injection preconditioning can relieve ventilator-induced brain injury in rats, and the mechanism may be related to inhibiting inflammatory responses and activating GABA signaling pathway.

SHENFU DECOCTION; Respiration, artificial; Brain injuries