Ninety-Day Nonylphenol Exposure May Cause Adverse Effects on Pancreatic Function in Adult SD Rats

[Objective] To examine the effects of exposure to nonylphenol(NP) for 90 days on pancreas and relevant indicators of blood glucose in rats. [Methods] Thirty-two adult male Sprague-Dawley(SD) rats were randomly divided into four groups, fed with NP by gavage at doses of 0, 40, 100, or 250 mg/kg body weight on alternate days for a period of 90 days respectively. Body weight, daily food and water intake, and blood glucose were measured regularly. After last gavage, insulin, hexokinase(HK), free fatty acids(FFA) in the serum were detected. Hematoxylin-eosin(HE) staining method and TdT-mediated dUTP nick end labeling(TUNEL) technique were used to analyze histological changes and cell apoptosis of pancreas. Pancreas coefficient, insulin sensitive index, and insulin secretion index were also calculated. [Results] Compared with the control group, the coefficient of pancreas(P 0.01), serum insulin(P 0.05), and serum HK were significantly decreased(P 0.01), while daily water intake and insulin sensitive index were increased(P 0.01) in the NP-administrated groups(40, 100, and 250 mg/kg). The size and number of islets were reduced. However, no apoptosis was found in the pancreatic cells. [Conclusion] It may speculate that 90-day exposure of NP poses some adverse effects on pancreatic function and has an impact on relevant indicators.