Figure 1.

Androgen receptor protein expression. AR protein expression was quantified in N27 cells and SN, ETC, hippocampus, and testes micropunches from young gonadally intact male rats (n = 3). Antibodies targeting either the NTD (AR N20) or the CTD (AR C19) of the AR were used. Low protein expression of full-length AR (110 kDa) was found in all samples, but high protein expression of AR fragments (70 and 30 kDa) was observed in fresh samples and to a lesser extent in frozen samples. Protein expression at 45 kDa (AR45) was observed in all samples and was unaffected by temperature (A). To determine the role of testosterone and age on AR45 expression, different hormone groups were used: N27 cells treated with vehicle control (n = 8) or 100 nM testosterone (n = 8) and SN from young and middle-aged male rats that were either gonadectomized (n = 3) or gonadally intact (n = 3; B, C). Testosterone did not affect AR45 expression in N27 cells. Neither hormones nor age affected AR45 expression in SN (B, C). C, control; T, testosterone; Ts, testes; YI, young gonadally intact male rats; YG, young GDX male rats; MI, middle-aged gonadally intact male rats; MG, middle-aged GDX male rats; SN, substantia nigra pars compacta; ETC, 2nd layer of the entorhinal cortex; Hipp, CA1 region of the dorsal hippocampus.