Singla Amika, Kaur Jaspreet, Mahmood Akhtar
Department of Biochemistry, Panjab University, Chandigarh 160 014, India.
J Appl Toxicol. 2006 Sep-Oct;26(5):397-401. doi: 10.1002/jat.1148.
The effect of feeding nickel (50 mg kg(-1) body weight) daily for 7 days was studied on the development of various brush border enzymes across the crypt-villus axis. The activities of brush border maltase (P < 0.05), lactase (P < 0.05), alkaline phosphatase (P < 0.05) and leucine amino peptidase (P < 0.05) were augmented in purified brush borders, whereas sucrase, trehlase (P < 0.01) and glutamyl transpeptidase (P < 0.05) were reduced in nickel fed animals compared with controls. Kinetic and heat inactivation studies with brush border sucrase and alkaline phosphatase confirmed these findings. Western blot analysis of alkaline phosphatase showed a strong signal for the enzyme protein but a reduced level of sucrase antigen in nickel fed rat intestine compared with the controls. These findings suggest that the expression of various brush border enzymes along the crypt-villus axis is modulated in rat intestine exposed to nickel, which may disrupt the digestive functions of the intestinal tissue.
研究了连续7天每天喂食镍(50毫克/千克体重)对沿隐窝-绒毛轴的各种刷状缘酶发育的影响。在纯化的刷状缘中,刷状缘麦芽糖酶(P<0.05)、乳糖酶(P<0.05)、碱性磷酸酶(P<0.05)和亮氨酸氨肽酶(P<0.05)的活性增强,而与对照组相比,喂食镍的动物中的蔗糖酶、海藻糖酶(P<0.01)和谷氨酰转肽酶(P<0.05)降低。对刷状缘蔗糖酶和碱性磷酸酶的动力学和热失活研究证实了这些发现。碱性磷酸酶的蛋白质印迹分析显示该酶蛋白有强烈信号,但与对照组相比,喂食镍的大鼠肠道中蔗糖酶抗原水平降低。这些发现表明,在暴露于镍的大鼠肠道中,沿隐窝-绒毛轴的各种刷状缘酶的表达受到调节,这可能会破坏肠道组织的消化功能。