Effects of Restraint Stress and Cadmium Chloride on the Liver Function of Female Wistar Rats (Rattus norvegicus)

Cadmium (Cd) and prolonged exposure to stress are associated with adverse health outcomes. Various studies have shown the impacts of stress and metal exposures on liver function. Cd is a non-redox metal, one of the important mechanisms underlying its toxicity is oxidative stress induction because of the generation of reactive species with the depletion of the antioxidant defense system. Cadmium and psychological stressors are known to affect the liver's functions. The study aimed to assess the impact of restraint stress and cadmium chloride administration on oxidative stress and liver functions in female Wistar rats. Twenty female Wistar rats (180-220g) were randomly divided into 4 groups (n=5 each): Control (CTL), Restraint stress (RSS), Cadmium chloride (CCC), Restraint+Cadmium (RSC). Experimental groups were administered a daily dose of 100 mg/kg/BW of Cadmium chloride and subjected to restraint stress via wire mesh for 30 minutes daily for 21 days. All rats were anaesthesized and sacrificed 24 hours after the last procedures. Blood was collected through cardiac puncture for biochemical analysis. Liver tissue was collected, homogenized and analyzed for biochemical assays and a part for histological analysis. Results showed that the weight gain difference and antioxidant enzymes decreased significantly (p<0.05) in RSC group when compared with the control. The findings also revealed that cadmium and restraint stress exposure induced hepatotoxicity with a significant difference in liver function markers. AST and ALT significantly increased (p<0.05) in RSC group when compared to RSS and CCC groups. Furthermore, ALP and TP showed significant increase (p<0.05) in RSC group when compared with other groups. The histological architecture of the livers was also distorted by restraint stress exposure and cadmium chloride administration. Overall, the findings established that both psychological and environmental stressors affect liver health, through different pathways.