SECRETION OF LIPASES IN THE DIGESTIVE TRACT OF THE CRICKET Gryllus bimaculatus.
SECRETION OF LIPASES IN THE DIGESTIVE TRACT OF THE CRICKET Gryllus bimaculatus.
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DOI：
10.1002/arch.21303
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发表时间：
2015-12
影响因子：
2.2
通讯作者：
Sandy Weidlich;K. Hoffmann;J. Woodring
中科院分区：
文献类型：
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作者：
Sandy Weidlich;K. Hoffmann;J. Woodring
由于对昆虫中脂肪酶分泌的部位和比例知之甚少，因此我们对摄食和未摄食的成年雌性双斑灰蛙的脂肪酶分泌进行了研究。在盲肠和胃中，被摄食的雌性所分泌的三酰甘油脂肪酶、二酰甘油酯脂肪酶和磷脂酰胆碱脂肪酶的比例为1：1.4：0.4。在没有喂食的雌性中，盲肠中的这些活动减少了30%-40%。盲肠中的总脂肪酶活性(TLA)约为胃中的10倍。最小的脂肪酶分泌发生在最后一次换羽之前和期间，在未喂食的蟋蟀中保持在这个水平，表明基本的分泌速度。在2日龄的喂食雌性幼虫中，整个肠道中约10%的TLA存在于作物中，约70%在盲肠，20%在胃，3%在回肠。胃中的脂肪酶被循环回盲肠，几乎不会在粪便中丢失。油酸能促进体外脂肪酶的分泌，而脂类不能。摄食刺激了脂肪酶的分泌，饥饿减少了脂肪酶的分泌，但这并不能证明是对分泌的直接调节，因为摄食也导致盲肠的大小和体积增加。
Little is known concerning the sites and the ratios of the lipase secretions in insects, therefore we undertook an examination of the lipase secretion of fed and unfed adult female Gryllus bimaculatus. The ratio of triacylglyceride lipase, diacylglyceride lipase, and phosphatidylcholine lipase secreted by fed females in the caecum and ventriculus is 1:1.4:0.4. These activities decrease in the caecum by 30-40% in unfed females. The total lipase activity (TLA) in the caecum is about 10 times that in the ventriculus. Minimal lipase secretion occurs before and during the final moult, and remains at this level in unfed crickets, indicating a basal secretion rate. In 2-day-old fed females, about 10% of the TLA in the entire gut is found in the crop, about 70% in the caecum, 20% in the ventriculus, and 3% in the ileum. Lipases in the ventriculus are recycled back to the caecum and little is lost in the feces. Oleic acid stimulated in vitro lipase secretion, but lipids did not. Feeding stimulated lipase secretion, starvation reduced lipase secretion, but this does not prove a direct prandal regulation of secretion, because feeding also induced a size and volume increase of the caecum.