Figure 4.

Influence of GH on the concentration of HNF-6 mRNA detected in rat liver by RNase protection assay. (A) Total RNA (20 μg) was incubated with an HNF-6 and a GAPDH riboprobe. After digestion with RNase, the protected fragments were separated on a 6% denaturing polyacrylamide gel. Each lane corresponds to an individual sample (two animals per experimental condition). Arrows point to the protected fragments expected for GAPDH mRNA (316 b), and for the short (254 b) and long (215 b) forms of HNF-6 mRNA (16). GH was administered for 7 days either by minipump infusion to mimic the female secretory pattern (lane d, 50 μg GH; lane e, 250 μg GH per 100 g body weight) or by daily injections of 12.5 μg GH to mimic the male secretory pattern and sacrificed 1 h (lane f), 3 h (lane g), or 6 h (lane h) after the last injection. (B) Relative concentration of HNF-6 mRNA short form (filled boxes) or long form (shaded boxes) in the liver of hypophysectomized female rats left untreated or treated with GH according to the corresponding protocol described under A above. Data are means ± SEM for the number of animals indicated above the bars.