Sex differences in, and gonadal hormone modulation of THC-induced catalepsy. Sham-gonadectomized females (sham F) and males (sham M), and gonadectomized (GDX) rats treated with no hormone (GDX+0), estradiol (+E2), progesterone (+P4), both ovarian hormones (+E2/P4), or testosterone (+T) were tested for catalepsy after completion of antinociceptive testing on the pre-chronic test day (pre) and the post-chronic test day (post). Each bar is the mean ± 1 SEM of 10–12 rats. *significant decrease in catalepsy from pre- to post-chronic tests.