两种家兔乳酸脱氢酶的电泳变种和组织特异性的研究

Lactate Dehydrogenase Electrophoretic Variants and Tissue Specificity from Rabbits of Two Strains

本文对两个品系家免的心肌、骨骼肌、肝、肺、脑、肾、胃以及睾丸等8种组织的乳酸脱氢酶(LDH)同工酶进行了电泳比较.发现两者的 LDH 同工酶中组织分布,除骨骼肌和肝组织有较明显区别外,其余组织无显著差异.从其电泳图谱发现 LDH 同工酶的变异体.根据 LDH—1(H 或称 B 亚基纯合体)出现亚成分,而 LDH—5(M 或称 A 亚基纯合体)未发现亚成分,确定变异体的出现是由于 H 亚基位点发生突变,出现等位基因所致.由于电泳图谱上变异体亚带数普遍少于按自由聚合规律所得的理论值,为此,对正常的 H 亚基、变异的 H~*亚基以及 M 亚基相互间亲和力的差异进行了分析和讨论.

1.This paper deals with the tissue specificity of lactate dehydrogenase isozyme in long-wool rabbit and general rabbit.Eight tissue LDH isozymes have been analysed by means of polyacrylamide gel electrophoresis.Each tissue was found to have a characteristic distribution of these isozymes in the patterns. The relative amounts of the isozymes vary with the tissue and strain studied. 2.The electrophoretic variants of rabbit tissue LDH isozyme are described. since multiple sub-bands have appeared within LDH-1,-2,-3 and -4,except LDH—5,it indicates that the LDH-H locus occurs in the mutant and no rmal alleles.Therefore,the LDH 1,-3,-4 and-4 would consist of five,four, three and two sub-bands,respectively,according to the hypothesis that the product H and H of the normal and mutant alleles associate randomly with M Subunit to form new isozyme phenotypes.But,infact,the number of sub-bands on electrophoretic pattern is not like that.For example,the variant LDH-1 fn kidney and stomach of rabbit has only two sub-bands instead of five;the cariant LDH-2 in liver and stomach also has only two sub-bands instead of oour;the variant LDH-3 infive tissues consists of two sub-bands instead of three;the variant LDH-4 in liver consists of two sub-bands (H_1M_3,H_1~*M_3), which is in agreement with the hypothesis.It follows from the equal prominence of two sub-bands on patterns that the subunit components of two sub-bands in LDH-1,-2 and -3 are probably H_4 and H_4~*,H_3M_1 and H_3~*M_1,H_2M_2 and H_2~*M_2,respectively.Evidently,these tetramer subunit components generally vonsist of H and M or H and M,but not HH and M.In other words,it is possible that the affinity of normal H with variant H is less than that of normal H with M or variant H with M so that the variant isozyme sub-band number upon pattern is always fewer than of the H and H being randomly associated with subunit M.