Objective: To study the efficacy of antisense oligonucleotide of neuropeptide Y (NPY) Y5 receptor on treating hyperleptinemia by intracerebral ventricular administration in diet-induced obese rats.Methods: The obese rats were prepared by feeding a high-nutritive diet for 7 weeks. The lateral ventricle of obese rats was cannulated. Either 10 μl of different neuropeptide Y Y5 receptor oligodeoxynucleotide, including antisense, sense and missense oligodeoxynucleotide (5 g/L) or 10 μl saline was administered into the ventricle through cannula three times per day in every rat. Two days later the rats were slaughtered .The weights of both retroperitoneal and epididymal adipose tissues were measured, and the serum insulin and leptin were detected by radioimmunoassay method and the murine leptin ELISA kit respectively. Results: ①The level of serum was significantly higher in experimental rats than that in normal rats. Similarly, the level of serum insulin and the weights of both retroperitoneal and epididymal adipose tissues were increased in experimental rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of serum leptin and insulin were significantly decreased and combined with the reduction of weight in retroperitoneal adipose tissue. There was, however, no significant difference in the weight of epidymal adipose tissue between pre-treated and post-treated duration. ③There was significant positive correlation among the level of serum leptin, the level of serum insulin and the weight of retroperritoneal adipose tissue in diet-induced obese rats. Conclusion: Intracerebral ventricular administration of antisense oligodeoxynucleotide of neuropeptide Y Y5 receptor may alleviate hyperleptinemia in diet-induced obese rats and decrease the weight of retroperitoneal adipose tissue and the level of serum insulin.
