title: [Lactate dehydrogenase isoenzymes from teleost fish retina, cardiac and skeletal muscle].
abstract: Kinetic analysis, electrophoresis and selective inactivation were used in studies of isozymic composition of LDH in the retina, cardiac and skeletal muscles in 8 species of marine teleost fishes. In the retina, the number of isoenzymes in all the fishes studied varied from 2 to 7, the predominant ones being B4 and E4. The isoenzyme E4 was found only in the retina of Hexagrammus octogrammus, Pleurogrammus monopterygius, Liopsetts pannifasciata, Limanda yokohamae, Eleginus gracilis, Therarga chalcogramma. In two last species, the electric charge of E4, B4 and A4 is opposite to that of the corresponding isoenzyme in terrestrial animals, resulting in opposite migration of these isoenzymes during electrophoresis. In the retina of fishes containing the isoenzyme E4, double heterotetramers B1E3, B2E2, B3E1 were also found. The retina in Leuciscus brandti, Clupea harengus harengus does not contain the isoenzyme E4. Investigation of the distribution pattern of the isoenzymes in cellular fractions of the retina in P. monopterygius revealed that hyaloplasm and nuclei contain A4, B4, B3E1, E2B2, E3B1 and E4, which corresponds to the situation found after the extraction of LDH from the whole retina tissue. In the mitochondria B4 and E4 were found, while in the outer segments--only B4. Skeletal muscles in all the fishes studied differ by the predominance of the isoenzyme A4 which is present as a sole component (P. monopterygius, H. octogrammus, L. pannifasciata, L yokohamae, L. brandti) or together with B4 (T. chalcogramma, C. harengus harengus). In the cardiac muscles of four species of fishes (except L. yokohamae, L. pannifasciata, H. octogrammus, P. monopterygius), the predominant isoenzyme was found to be B4, although the total number and the ratio of the isoenzymes varied: A4, A2B2, B4 (E. gracilis), A4B4 (T. chalcogramma, C. harengus harengus), A4, A3B1, A2B2, A1B3, B4 (L. brandti). The LDH in the heart of L. yokohamae, L. pannifasciata, H. octogrammus, P. monopterygius has only one isoenzyme A4.
mesh_terms: D000818:Animals; D005399:Fishes / Q000378:metabolism*; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D009132:Muscles / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology; D012160:Retina / Q000201:enzymology; D013045:Species Specificity
chemical_list: D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase
vernacular_title: Izofermenty laktatdegidrogenazy setchatki, serdechnoĭ i skeletnoĭ myshts kostistykh ryb