Sepsis produces depression of testosterone and steroidogenic acute regulatory (StAR) protein

The hypothesis that induction of chronic peritoneal sepsis would produce de pression of serum testosterone due to a decrease in Leydig cell steroidogen ic acute regulatory (StAR) protein or P450c17 steroidogenic enzyme was test ed. Male Sprague-Dawley rats (350-400 g) were randomized to septic and nons eptic groups. Sepsis was induced with a cecal slurry (200 mg/kg in 5 mt of 5% dextrose in water (D5W); intraperitoneal) while nonseptic rats received only sterile D5W. Animals (n = 6, in each group) were killed by CO2 asphyxi ation and blood samples were collected by direct cardiac puncture at 24 h a fter induction of sepsis/sham sepsis. The serum concentration of corticoste rone, progesterone, estradiol, and testosterone was determined using radioi mmunoassay. Western blot analysis was utilized to quantify Leydig cell StAR protein and P450c17 enzyme. Sepsis produced a significant decrease in the serum concentration of testosterone, a down-regulation of StAR protein, and an increase in serum estradiol 24 h after induction of sepsis (as compared with the nonseptic group). Protein levels of P450c17 in Leydig cells and s erum concentrations of progesterone and corticosterone 24 h after induction of sham sepsis or sepsis were not different. It is concluded that the decr eases in serum testosterone after 24 h of chronic peritoneal sepsis correla ted with reductions in StAR protein.