Unité mixte de recherche Stress Environnementaux et Biosurveillance des milieux aquatiques (UMR-I 02 SEBIO), Reims, France.
Institut National de l'Environnement Industriel et des Risques (INERIS), Unité d'Ecotoxicologie in vitro et in vivo (ECOT), Verneuil-en-Halatte, France.
PLoS One. 2018 Apr 3;13(4):e0194932. doi: 10.1371/journal.pone.0194932. eCollection 2018.
Determining digestive enzyme activity is of potential interest to obtain and understand valuable information about fish digestive physiology, since digestion is an elementary process of fish metabolism. We described for the first time (i) three digestive enzymes: amylase, trypsin and intestinal alkaline phosphatase (IAP), and (ii) three gut morphometric parameters: relative gut length (RGL), relative gut mass (RGM) and Zihler's index (ZI) in threespine stickleback (Gasterosteus aculeatus), and we studied the effect of temperature and body size on these parameters. When mimicking seasonal variation in temperature, body size had no effect on digestive enzyme activity. The highest levels of amylase and trypsin activity were observed at 18°C, while the highest IAP activity was recorded at 20°C. When sticklebacks were exposed to three constant temperatures (16, 18 and 21°C), a temporal effect correlated to fish growth was observed with inverse evolution patterns between amylase activity and the activities of trypsin and IAP. Temperature (in both experiments) had no effect on morphometric parameters. However, a temporal variation was recorded for both RGM (in the second experiment) and ZI (in both experiments), and the later was correlated to fish body mass.
测定消化酶活性对于了解鱼类消化生理学具有潜在的意义，因为消化是鱼类代谢的基本过程。我们首次描述了（i）三种消化酶：淀粉酶、胰蛋白酶和肠碱性磷酸酶（IAP），以及（ii）三种肠道形态计量学参数：相对肠道长度（RGL）、相对肠道质量（RGM）和 Zihler 指数（ZI）在三刺鱼（Gasterosteus aculeatus）中，并研究了温度和体型对这些参数的影响。在模拟温度季节性变化时，体型对消化酶活性没有影响。淀粉酶和胰蛋白酶活性的最高水平出现在 18°C，而 IAP 活性的最高水平出现在 20°C。当三刺鱼暴露于三种恒温（16、18 和 21°C）时，观察到与鱼类生长相关的时间效应，淀粉酶活性与胰蛋白酶和 IAP 活性之间呈相反的演变模式。温度（在两个实验中）对形态计量学参数没有影响。然而，在第二个实验中记录到 RGM 的时间变化（在第二个实验中）和 ZI（在两个实验中），并且后者与鱼体质量相关。
