Objective: To investigate the protective effect of somatostatin (SS) on acute kidney injury (AKI) of paraquat (PQ) poisoned mice and its mechanism. Methods: From December 2017 to April 2018, a total of 48 SPF male BALB/C mice were selected and randomly divided into 4 groups, with 12 mice in each group: Control group, SS group (20 mg/kg SS was injected 1 hour before and 3 hours after gavage with normal saline) , PQ group (2% PQ 60 mg/kg by gavage) and PQ+SS group (Intragastric administration was performed with 2% PQ solution of 60 mg/kg, and 20 mg/kg SS was administered 1 h before and 3 h after intragastric administration) , 12 mice in each group were observed for the general situation and behavioral effects. After 24 hours of modeling, mice were sacrificed.Then blood was extracted after eyeball was removed, and both kidneys were removed by laparotomy. Serum IL-6, TNF-α and MPO levels were determined by ELISA. The characteristic pathological changes of toxic renal tubular injury were observed under light microscope and scored accordingly. The changes of NF-κB expression were detected by Western-Blot, SOD, Caspase-3 and malondialdehyde (MDA) were detected by chemical colorimetry. Results: Mice in Control group and SS group showed normal general conditions and behaviors; Mice in PQ group were significantly worse than those in Control group, showing decreased feeding and activity, dry fur, hair shedding and listless spirit; The above symptoms in the mice of PQ+SS group were alleviated compared with the PQ group. Under the light microscope, the renal tissue structure of PQ group was obviously disordered and severely damaged, and the nephropathy score was (6.14±0.72) . The performance of PQ+SS group under light microscope was improved compared with PQ group, and nephropathy score (4.36±0.42) decreased (P<0.05) . Compared with the Control group, serum TNF-α (39.89±3.32) pg/ml, IL-6 (77.29±4.77) pg/ml, renal NF-κB (2.29±0.097) , MPO (0.31±0.017) μg/ml, MDA (0.91±0.03) mmol/mg prot, and Caspase-3 (376.51±8.24) % levels were significantly increased in the PQ group, while the level of renal SOD (2.36±0.73) U/mg prot was significantly decreased (P<0.05) . Compared with the PQ group, serum TNF-α (33.82±1.57) pg/ml, IL-6 (58.49±5.89) pg/ml, renal NF-κB (0.84±0.05) , MPO (0.22±0.01) μg/ml, MDA (0.72±0.05) mmol/mg prot, Caspase-3 (327.32±21.93) % decreased significantly, and renal SOD (4.90±0.81) U/mg prot increased significantly in the PQ+SS group (P<0.05) . Conclusion: PQ poisoning can lead to AKI in mice, while SS can reduce AKI caused by PQ poisoning, improve the general survival state of PQ poisoned mice, and play a certain protective role in kidney injury caused by PQ poisoning, which may be achieved by inhibiting oxidative stress response, inflammatory response and apoptosis caused by poisoning.
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