The investigation of leptin synthesis and serum levels in diet induced obese rats subsequent to retroperitoneal adipose tissue denervation

Leptin is a hormone synthesized mainly in white adipose tissue and that regulates the energy balance. Synthesis of leptin is regulated by the sympathetic nervous system as well as a number of other factors. In our study, we aim to investigate the effects of retroperitoneal fat tissue denervation (both sides) on mRNA expression of leptin in the fat tissue and in the serum concentrations in rats fed with standard and high fat diet. In our study, there will be four experimental groups each containing 8 Sprauge Dawley rats weighing 100-150 g and aging 3-5 weeks: I. Group: Denervated of both retroperitoneal tissue and fed high fat rat diet (YD+), II. Group: Not Denervated and fed with high fat rat diet (YD-), III. Group: Denervated of both retroperitoneal tissue and fed standart fat rat diet (SD+), IV. Group: Not Denervated and fed with standart rat diet (SD-) (control group). At the end of 10 week period, the animals tissue and serum samples were collected. In serum samples measured glucose, triglyceride, insulin and leptin levels. Furthermore, in retroperitonel ve epididimal tissue samples leptin mRNA levels were determined by using RT-PCR. Serum leptin levels were determined to be higher in high-fat diet and denervated group compared to the control group (p=0.038). Denervation with high fat diet did not altered gene expressions (p=0.31). In conclusion, the denervated rats, there was no difference in the leptin expression. On the other hand, serum leptin levels showed significant changes. The observed changes, were considered to be caused by dietary effects to other fat tissues.