齐口裂腹鱼生长、肌肉品质和脂蛋白脂酶及脂肪酸合成酶基因表达的研究

目的：研究不同生长阶段齐口裂腹鱼的生长状况、肌肉品质和脂蛋白脂酶（lipoprotein lipase，LPL）及脂肪酸合成酶（fatty acid synthetase，FAS）的基因表达。方法：分别选取齐口裂腹鱼幼鱼（137.8±1.7） g（S组）、亚成鱼（312.4±11.8） g（M组）、成鱼（500.9±31.4） g（L组），测定形体指标、脏器指数和肌肉主要营养成分含量，并采用实时荧光定量聚合酶链式反应测定LPL及FAS的基因表达水平。结果：与S组相比，M组、L组肥满度、肝体比、肠脂比、水分含量均有所降低（P＜0.05），粗蛋白、粗灰分含量变化不大；L组肌间脂肪（intermuscular fat，IMF）含量最低（P＜0.05）；而S组、M组与L组肝胰脏中LPL mRNA及FAS mRNA表达水平均基本高于肌肉（P＜0.05），且L组肝胰脏中LPL mRNA及FAS mRNA表达水平均最低（P＜0.05），M组肌肉中LPL mRNA及FAS mRNA表达水平最高（P＜0.05）。结论：齐口裂腹鱼的肌肉主要营养成分含量在成鱼阶段有所降低，且IMF含量与LPL mRNA及FAS mRNA表达水平呈一定正相关。

Growth,Muscle Quality and Gene Expression of Lipoprotein Lipase and Fatty Acid Synthase of Schizothorax prenanti Tchang

Objective: To investigate the growth, muscle quality and gene expression of lipoprotein lipase (LPL) and fatty
acid synthase (FAS) of Schizothorax prenanti Tchang (SPT) at different growth stages. Methods: SPT with body weights of
(137.8 ± 1.7) g (small, juvenile), (312.4 ± 11.8) g (medium, subadult) and (500.9 ± 31.4) g (large, adult) were collected,
respectively. Their body condition indexes, visceral indexes and major muscle nutrients were determined. Meanwhile, LPL
and FAS mRNA levels in liver and muscle of SPT at the juvenile, subadult and adult growth periods were evaluated by realtime
PCR. Results: Compared with the small group, boby condition indexes, hepatopancreas index (HIS), mesenteric lipid
index and water content were reduced in the medium group and large group (P < 0.05). The contents of crude protein and
crude ash showed no significant change in muscle. The intermuscular fat was the least abundant in the large group (P < 0.05).
The LPL and FAS mRNA expression levels in liver for the small group, medium and large group were significantly higher
than in muscle (P < 0.05). The LPL mRNA and FAS mRNA expression levels in liver were the lowest in the large group
(P < 0.05). The LPL mRNA and FAS mRNA expression levels in muscle were the highest in the medium group (P < 0.05).
Conclusion: The essential nutrients in muscle are reduced at the adult stage, and the content of intramusclar fat is correlated
with the expression of LPL mRNA and FAS mRNA.