Chmielnicka J, Zareba G, Grabowska U
Department of Toxicological Chemistry, Medical University, Lódź, Poland.
Ecotoxicol Environ Saf. 1992 Dec;24(3):266-74. doi: 10.1016/0147-6513(92)90002-k.
In the present study the lowest p.o. doses of tin affecting heme biosynthesis in rabbits were determined and the protective effect of zinc on these disorders was evaluated. The experiment was performed on female rabbits who received per os single doses of SnCl2 x 2 H2O (10, 100, and 200 mg Sn/kg) and ZnSO4 (50 mg Zn/kg s.c.). The activities of delta-aminolevulinic acid dehydratase (ALA-D) in the whole blood, free erythrocyte propoporhyrins, urine delta-aminolevulinic acid, and coproporphyrins (CP-U) were determined. In animals administered tin at a dose of 100 mg Sn/kg, ALA-D activity decreased by about 80% and two- to threefold increases in the ALA and CP concentrations in urine were observed. A protective effect of zinc with respect to ALA-D activity was noticed in both groups (100 and 200 mg Sn/kg) after combined administration of both metals. Results of an interaction between zinc and tin were also observed to reduce ALA levels in urine, whereas zinc did not protect against an effect of tin on CP excretion.
在本研究中，确定了影响家兔血红素生物合成的最低口服锡剂量，并评估了锌对这些紊乱的保护作用。实验选用雌性家兔，经口给予单剂量的SnCl₂·2H₂O（10、100和200mg锡/千克）和ZnSO₄（50mg锌/千克，皮下注射）。测定全血中δ-氨基乙酰丙酸脱水酶（ALA-D）的活性、游离红细胞原卟啉、尿δ-氨基乙酰丙酸和粪卟啉（CP-U）。给予100mg锡/千克剂量锡的动物，ALA-D活性降低约80%，尿中ALA和CP浓度升高2至3倍。两种金属联合给药后，在两组（100和200mg锡/千克）中均观察到锌对ALA-D活性的保护作用。还观察到锌与锡相互作用的结果可降低尿中ALA水平，而锌不能防止锡对CP排泄的影响。
