Arienti G, Leat W M, Harrison F A
Q J Exp Physiol Cogn Med Sci. 1975 Jan;60(1):15-24. doi: 10.1113/expphysiol.1975.sp002286.
Sheep pancreatic juice was found to contain at least two enzymes which hydrolysed biliary lecithin. One enzyme was heat and acid labile and hydrolysed the fatty acid from position 1 (phospholipase A1); the other was heat and acid stable hydrolysing the fatty acid at position 2 (phospholipase A2). Lysophospholipase activity was also present. The phospholipases were active at pH values greater than 4.2, and would therefore function in the acid conditions (pH 3-6) of the sheep small intestine. The activity of the pancreatic phospholipases, and A2 in particular, was dramatically stimulated by the presence of the secretions of Brunner's glands which could be important in accelerating the hydrolysis of biliary lecithin in the lumen of the intestine. Phospholipase A1 was sensitive to acid in the range pH 2.5-3.5 and could therefore be partially inactivated by abomasal digesta; but phospholipase A2 was resistent to acid treatment.
发现绵羊胰液中至少含有两种可水解胆汁卵磷脂的酶。一种酶对热和酸不稳定，可水解1位上的脂肪酸（磷脂酶A1）；另一种酶对热和酸稳定，可水解2位上的脂肪酸（磷脂酶A2）。同时也存在溶血磷脂酶活性。这些磷脂酶在pH值大于4.2时具有活性，因此能在绵羊小肠的酸性环境（pH 3 - 6）中发挥作用。胰腺磷脂酶，尤其是A2的活性，会因布伦纳腺分泌物的存在而受到显著刺激，这在加速肠腔内胆汁卵磷脂的水解过程中可能具有重要意义。磷脂酶A1在pH 2.5 - 3.5范围内对酸敏感，因此可能会被皱胃消化物部分灭活；但磷脂酶A2对酸处理具有抗性。
