Fig. 4.
Effect of ACTH on P450scc hnRNA and mRNA levels in the adrenal cortex. P450 hnRNA (A) and mRNA (B) were measured using reverse transcript and qRT-PCR. Data are normalized to GAPDH mRNA levels (not shown) and are expressed as fold induction over nonsuppressed controls infused with saline (CONTROL-SAL). A, P450scc hnRNA. MP-suppressed rats infused with saline (MP-SAL, n = 9) showed decreased P450scc hnRNA, compared with CONTROL-SAL (n = 8). P450scc hnRNA were increased in ACTH RISING (n = 5) but not in ACTH FALLING (n = 4). P450scc hnRNA levels were lower in rats infused with constant ACTH (ACTH CONST, n = 8). There was a difference between ACTH RISING and ACTH FALLING. B, P450scc mRNA. MP-suppressed rats infused with saline (MP-SAL, n = 9) showed decreased P450scc mRNA compared with CONTROL-SAL (n = 8). P450scc mRNA was increased in both ACTH RISING and ACTH FALLING. P450scc mRNA levels were lower in rats infused with constant ACTH (ACTH CONST, n = 8). *, P < 0.05 vs. CONTROL-SAL; #, P < 1 × 10−5 vs. MP-SAL; $, P < 0.0005 vs. ACTH RISING. (See Results for detailed P values.)