Walther F J, Batenburg J J
Department of Pediatrics, King/Drew Medical Center, Los Angeles, Calif., USA.
Biol Neonate. 1995;68(2):128-34. doi: 10.1159/000244228.
In fetal lung the amounts of mRNAs encoding fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC) and ATP citrate lyase (ACL) increase in late gestation and drop around birth. To study the mechanism of the perinatal decrease, pregnancy was prolonged from 22 (term) to 25 days in rats with daily injections of progesterone. Progesterone did not affect the levels of lipogenic enzyme mRNAs in fetal lung prior to term, but significantly delayed the perinatal decrease in the levels of lung FAS and ACC mRNA. Although for ACL mRNA abundance the differences were not statistically significant, its pattern in the control and progesterone groups were similar to those of FAS and ACC mRNA. Malic enzyme mRNA did not change between 20 and 25 days after conception in either group. These results suggest that the decrease in FAS and ACC mRNA at term can be partially explained by labor, delivery, air-breathing or switch from carbohydrate to fat metabolism.
在胎儿肺中，编码脂肪酸合酶（FAS）、乙酰辅酶A羧化酶（ACC）和ATP柠檬酸裂解酶（ACL）的mRNA量在妊娠后期增加，并在出生前后下降。为了研究围产期下降的机制，通过每日注射孕酮将大鼠的妊娠期从22天（足月）延长至25天。孕酮在足月前不影响胎儿肺中脂肪生成酶mRNA的水平，但显著延迟了肺FAS和ACC mRNA水平的围产期下降。尽管ACL mRNA丰度的差异无统计学意义，但其在对照组和孕酮组中的模式与FAS和ACC mRNA相似。两组在受孕后20至25天之间苹果酸酶mRNA均未发生变化。这些结果表明，足月时FAS和ACC mRNA的下降部分可由分娩、呼吸或从碳水化合物代谢向脂肪代谢的转变来解释。
