Nakagawa K, Asami M, Kuriyama K
Jpn J Pharmacol. 1983 Feb;33(1):9-15. doi: 10.1254/jjp.33.9.
The mode of the inhibitory effect of lead ion on the release of enzymes from cerebral lysosomes isolated from young Wistar rats was examined. The incubation of cerebral lysosomes in a low pH medium or with adenosine triphosphate (1 mM) at neutral pH resulted in the decrease of the release of acid phosphatase (EC 3.1.3.2) and beta-N-acetylglucosaminidase (EC 3.2.1.30) activities. Multivalent cations such as Mn2+, Co2+ and La3+ inhibited the enzyme release, while Ca2+ facilitated the release. On the other hand, lead ion suppressed the Ca2+-induced enzyme release, but this suppressive effect of lead ion was eliminated by the treatment of lysosomes with phospholipase C and phospholipase A2. These results suggest that lead ion may alter the ionic permeability of cerebral lysosomal membrane by reacting with membraneous phospholipids, and thus may prevent the release of lysosomal enzymes in vitro.
研究了铅离子对从幼年Wistar大鼠分离的脑溶酶体中酶释放的抑制作用模式。在低pH介质中或在中性pH下与三磷酸腺苷（1 mM）一起孵育脑溶酶体，导致酸性磷酸酶（EC 3.1.3.2）和β-N-乙酰氨基葡萄糖苷酶（EC 3.2.1.30）活性的释放减少。多价阳离子如Mn2+、Co2+和La3+抑制酶的释放，而Ca2+促进释放。另一方面，铅离子抑制Ca2+诱导的酶释放，但通过用磷脂酶C和磷脂酶A2处理溶酶体，铅离子的这种抑制作用被消除。这些结果表明，铅离子可能通过与膜磷脂反应改变脑溶酶体膜的离子通透性，从而在体外阻止溶酶体酶的释放。
