Ottolenghi A, Weatherly N F, Larsh J E
Infect Immun. 1980 Aug;29(2):799-807. doi: 10.1128/iai.29.2.799-807.1980.
After a primary infection with 100 Angiostrongylus cantonensis larvae, infected rats showed elevated phospholipase B activity in meningeal and brain homogenates beginning with the first week and continuing through the first month of infection. The rise in phospholipase B values through the first 4 weeks, with a prolonged peak spanning days 30 to 31, coincided with the invasion and maturation of the parasites in the brain, and the ensuing sharp decline in phospholipase B levels, shown by the readings on day 45, coincided in turn with the known migration of the worms from the brain to the lungs, which begins about 5 weeks after infection. In the meninges, the pattern of enzyme elevation was generally similar to that in the brain samples except that the highest activity was seen earlier at days 8 to 9, followed by a gradual decline by days 30 to 31 and a sharper drop by day 45. Rats challenged with 100 larvae 53 days after the primary infection exhibited an almost immediate rise of phospholipase B activity in both the brain and meninges; the peaks of activity occurred at day 1 for the meninges and day 25 for the brain, and levels above control values were still present at day 50. Comparison of the total enzymatic content of the cerebral tissue and meninges revealed that a remarkably high proportion of the phospholipase B activity was contained in the meninges. The inference that elevated levels of this enzyme in the cerebral tissue of A. cantonensis-infected rats are due to inflammatory reactions within the meningeal envelopes was confirmed by histochemical demonstration of specific sites of enzymatic activity limited to the meninges. It is of interest that 80% of the cells positive for the enzyme were clearly identifiable as eosinophils since an association of bone marrow eosinophilia and high phospholipase B levels in rats infected with A. cantonensis was shown in our earlier study of rats infected with this parasite.
用100条广州管圆线虫幼虫进行初次感染后，感染的大鼠从感染第一周开始直至感染第一个月，脑膜和脑匀浆中的磷脂酶B活性均升高。在最初4周内磷脂酶B值升高，第30至31天出现一个持续时间较长的峰值，这与寄生虫在脑内的侵入和成熟相吻合，而第45天的读数显示，随后磷脂酶B水平急剧下降，这又与已知的蠕虫从脑向肺的迁移相吻合，这种迁移在感染后约5周开始。在脑膜中，酶活性升高的模式与脑样本中的大致相似，只是在第8至9天酶活性最高，随后在第30至31天逐渐下降，到第45天下降更为明显。在初次感染53天后用100条幼虫攻击的大鼠，其脑和脑膜中的磷脂酶B活性几乎立即升高；脑膜活性峰值出现在第1天，脑活性峰值出现在第25天，到第50天仍高于对照值。对脑组织和脑膜的总酶含量进行比较发现，磷脂酶B活性有相当高的比例存在于脑膜中。广州管圆线虫感染大鼠脑组织中该酶水平升高是由于脑膜包膜内的炎症反应这一推断，通过酶活性特定部位仅限于脑膜的组织化学证明得到了证实。有趣的是，80%的酶阳性细胞可明确鉴定为嗜酸性粒细胞，因为在我们早期对感染该寄生虫的大鼠的研究中发现，感染广州管圆线虫大鼠的骨髓嗜酸性粒细胞增多与高磷脂酶B水平有关。
