Fig. 2

Plasma steroid hormone concentrations of aged good and poor learners and young rats (n = 10, each). T, testosterone; Prog, progesterone; E2, 17β-estradiol; 4A, 4-androstenedione; AD, androstanediol-3α,17β; DHT, dihydrotestosterone; 17OHP, 17-hydroxyprogesterone; B, corticosterone. Horizontal and vertical bars indicate statistically significant differences between groups. Given are the means with standard deviation