Effects Of Androgen On The Insulin Sensitivity And Plasma Lipids Levels In Castrated Male Rats

Objective: This study was designed to examine the change of insulin sensitivity and levels of plasma lipids in castrated male rats and investigate the effects of physiological dose of TU and DHEAs treatment on them.Methods: In order to examine the effects of androgen on insulin sensitivity, 50 male SD rats were castrated (n=40) or sham-operated (n=10). 2 weeks after the operation, all of the survived 40 castrated rats were randomly assigned into four equal groups and treated with TU 4mg/kg/2weeks intramuscular injection (TU group, n=10), DHEA 5mg/kg/day oral administration (DHEA group, n=10), tea seed oil intramuscular injection (Castrated group 1, n=10) or NS oral administration (Castrated group 2, n=10) throughout the 6-week course of the experiment. And then, animals' blood samples were taken to assess the level of hormone, plasma lipids, fasting blood glucose and fasting insulin. Insulin sensitivity was followed by euglycaemic, hyperinsulinaemic glucose clamp measurements. At the end of the experiment, rats were killed to obtain their hearts and aortas for pathobiology.Results: 1.Substitution of castrated rats with TU and DHEA can restor their serum TT concentrations to the normal range. Their weigh growth was repressed at the same time. 2. Serum TG, LDL-C and FINs levels in castrated rats declined after TU and DHEA treatment. But the levels of FBG didn't show marked difference in these five groups. 3. Castration was followed by a marked insulin resistance in the clamp measurements. 4. Androgen substitution treatment can inhibit the necrosis of aortic endothelial cells and maintain the structure of cardiac muscle and blood vessel in castrated rats.Conclusions: Serum TG, LDL-C and FINs levels increased after castrated inmale rats. But their serum TT, DHEAs levels decreased and was paralleled by diminished insulin stimulation. Physiological dose of TU and DHEA treatment can remain normal serum TT level as well as improving insulin sensitivity. Androgen may become the ancillary drug which cures metabolic syndrome.