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At least 1,315 records · Page 73Linked to original sources
PubMed1990

Calcium transport activities of plasma membranes isolated from the livers of various animal species.

1. Plasma membranes of comparable yield and purity were isolated from the livers of various animal species belonging to phylogenetic groups from Amphibia to Mammalia. 2. Calcium transport activity was observed in all liver plasma membranes examined. 3. No phylogenetic pattern of expression of the liver plasma membrane calcium transport system was observed, with the order of activity being: guinea pig greater than rabbit greater than frog greater than chicken = hamster greater than rat = budgerigar = turtle greater than beef cattle greater than mouse = duck. 4. Calcium transport activity was only 9.7 and 8.7% of adult frog levels in plasma membranes isolated from the livers of tadpoles without and with limbs, respectively. 5. Liver plasma membrane calcium transport activity was 25% higher in adult chickens than in day-old chicks. 6. A possible role for thyroid hormone in the development of the liver plasma membrane calcium transport system is discussed.

Animals↗
PubMed1985

Phylogenetic examination of vertebrate central nervous system myelin proteins by electro-immunoblotting.

Central nervous system (CNS) myelin proteins from vertebrate classes were examined by immunoblotting with antisera against mammalian CNS myelin proteins. Higher vertebrates possessed proteolipid (PLP), DM-20 and Wolfgram (WP) proteins, except that DM-20 was missing in amphibia. Fish CNS myelins contained neither PLP nor WP; instead they bound antisera to mammalian peripheral nervous system P0 protein. All classes carried myelin basic protein, but only mammals exhibited a component equivalent to rat 21.5K (21,500 dalton). These phylogenetic data are consistent with major changes in CNS myelin protein composition at the transition from fishes to higher vertebrates.

Animals↗
PubMed1992

Müller (glial) cells in the retina of urodeles and anurans reveal different morphology by means of freeze-fracturing.

Müller (glial) cells of the retina of various species of amphibia (urodeles and anurans) were investigated by means of the freeze-fracture technique. This was done because Müller cells in anamniotes were believed to differ from those in mammals in that they should lack the so-called orthogonal arrays of particles (OAP) which are a characteristic feature of Müller cells in mammalian retina. However, as we could demonstrate previously (Berg-von der Emde and Wolburg, Glia, 2 (1989) 458), fish retinal Müller cells also contain OAP in their membranes suggesting that OAP are a general marker of Müller cells in all vertebrates. As demonstrated in this study, Müller cells of urodeles (Batrachoseps attenuatus and Pleurodeles waltlii) are OAP-positive, whereas two anurans (Rana esculenta and Xenopus laevis) do not reveal any OAP in their Müller cell membranes. Under phylogenetic aspects, it appears very interesting that frogs are as yet the only vertebrate group that deviates from all other vertebrates in terms of Müller cell membrane morphology.

Animals↗
PubMed1984

The effects of environmental factors on the development, behaviour and survival of Paramphistomum microbothrium miracidia.

The effects of temperature, hydrogen ion concentration, salts, light, gravity and living organisms on the development, survival and behaviour of Paramphistomum microbothrium miracidia were studied. Isotonic water environment of pH 7-8 and temperature of 25 degrees C were found to be most favourable for miracidial development and hatching. Miracidia longevity was highest at 21 degrees C in an isotonic water environment of pH 6-8. Demineralized water reduced the longevity of miracidia. Miracidia exhibit a strong phototaxis and a weak geotaxis, the latter being manifested only in the absence of light, and they show a preference for a medium with a low Ca/Mg ratio. An unidentified fungus, probably of the group of Fungi Imperfecti, had a deleterious effect on egg development. Aquatic organisms such as molluscans, dipterans and amphibia affect the survival of the miracidia. The relationship between observed phenomena and dynamics of infection are discussed.

Abattoirs↗
PubMed1977

Gluconeogenesis in vertebrate livers.

1. The hypothesis is advanced that it would be logical for a tissue (liver) to evolve as a gluconeogenic organ in order to recover the lactate produced as a result of rapid and sustained contraction of skeletal muscle. 2. Lactate was present in skeletal muscle of all animals examined and increased following electrical stimulation. It was also present in the blood. 3. Gluconeogenesis from lactate occurred in liver slices of all animals excepting amphibia. However, livers of these animals also contained much glycogen and are probably gluconeogenic. 4. Phosphoenolpyruvate carboxykinase was present in all animals investigated; pyruvate carboxylase was present in all animals excepting the toad.

Ambystoma↗
PubMed1977

Occurrence and properties of low molecular weight RNA components from cells at different taxonomic levels.

1. The occurrence and gel electrophoretic properties of low molecular weight RNA components (LMW RNA) have been studied in species at different taxonomic levels. The LMW RNA components apart from tRNA, 5S RNA and 5.5S RNA are called LMW*RNA. 2. The major components of LMW*RNA in mammalian cells are L, A, C and D, accounting for 0.1-0.7% of cellular RNA. The gel electrophoretic migration of components L, C, and D is similar in different mammals but the migration of component A shows differences. 3. Amphibia, reptiles and birds contain L, A, C and D in about the same amounts as mammals but slight differences in migration are seen for L, C and D. Component A is absent from the nucleated red blood cells of the chicken and the frog. 4. Sea urchins contain three LMW*RNA components with migrations different from L, A, C and D. These components account for about 0.1% of the cellular RNA. 5. Insects contain only one LMW*RNA component, migrating as component L. 6. Tetrahymena, Physarum and Mycoplasmas have one component which may be a counterpart to component L in higher cells. Yeast shows no LMW*RNA components. 7. In the multicellular species the occurrence and gel electrophoretic migration of LMW*RNA components are not related to tumorigenicity, developmental stage or origin of tissue.

Animals↗
PubMed1983

Pharmacology and physiology of monoamine oxidase activity in vertebrates--a comparative study.

Monoamine oxidase (MAO) activity is high in brain, where it regulates neurotransmitter levels, and in the 'detoxifying' organs. Two MAO isoenzymes (A and B) apparently exist in terrestrial tetrapods, but only one form (type A-like) can be detected in teleosts and in aquatic amphibia. MAO activity is regulated by both endogenous (hormones, substrates) and exogenous (daylength, temperature) factors.

Animals↗
PubMed1983

Density distribution, characterization and comparative aspects of plasma lipoproteins in the salamander, Pleurodeles waltii.

Blood plasma from a Urodele amphibian, Pleurodeles waltii, has been found to contain very-low density, low-density and high-density lipoproteins (VLDL, LDL and HDL, respectively). HDL and LDL predominated (concentration range 72-114 and 51-101 mg/dl) with lesser quantities of VLDL (23-51 mg/dl). Following isolation by density gradient ultracentrifugation, the physicochemical properties (morphology, particle size, hydrated density, electrophoretic mobility, and chemical composition) of the three major classes resembled, but were not identical with, those of the corresponding fractions in normal human plasma. The protein moieties of VLDL and LDL consisted mainly of polypeptides of high molecular weight (Mr greater than 60,000), which in their solubility were akin to human apo-B; smaller amounts of another protein migrated to the position of human apo-C-III in basic polyacrylamide gels. The major HDL apolipoproteins were of Mr 31,000 and 27,000, with minor amounts of 13,000, 61,000 and 76,000 components; in alkaline, urea-containing polyacrylamide gels, these major proteins migrated faster than the major components (apo-AI and apo-AII) of human HDL. Immunochemically, lipoproteins with pre-beta-, beta- and alpha-mobility were detected in the VLDL, LDL and HDL, respectively. Salamander VLDL and LDL were found to share an antigenic site(s) with the LDL of trout, chicken and guinea-pig, suggesting the presence of an apo-B-like protein. The chemical compositions and immunochemical reactions of salamander lipoproteins indicate that their structure and metabolism resemble that of other amphibia, reptiles and fish rather more closely than that of most mammals and birds.

Animals↗
PubMed1986

Presence of O6-methylguanine acceptor protein in the tissues of different classes of vertebrates and invertebrates.

We have measured the ability of extracts of tissues from several species of mammals, birds, reptiles, amphibia and fish to demethylate adducts of O6-methylguanine in exogenous DNA by transfer of the methyl group to an acceptor protein. Our study also encompassed tissues from a smaller number of invertebrates, from arthropods, molluscs and annelids. The vertebrate tissues used were liver, brain, spleen and kidney. In the case of the invertebrates we sampled liver, neural tissue, gonads, digestive tract and hepatopancreas. There was no consistent change in the amount of acceptor activity per unit of protein or DNA going from cold-blooded to warm-blooded vertebrates. Liver invariably had the highest amount; this finding was not unexpected since metabolic processes in the liver are high, and good cellular protective mechanism important. Inter-class comparisons within the vertebrates are highly speculative, and hindered by the fact that there is little information on carcinogenesis in animals other than rodents and humans. O6-methylguanine acceptor activity was found in all the invertebrate tissues tested. The amounts were variable, 0.003-0.0051 fmol/micrograms cellular DNA, but the values fell within the range of those found in the tissues of vertebrates.

Amphibians↗
PubMed1987

A glycosylated proteolipid protein is common to CNS myelin of recent lungfish (Ceratodidae, Lepidosirenidae).

1. Myelin proteins from the CNS of recent lungfish (Lepidosiren paradoxa, Protopterus dolloi, Neoceratodus forsteri) were separated and analysed by staining and immunoblotting. 2. All species showed a glycosylated component (g-PLP) that cross-reacted with antibodies against tetrapod proteolipid protein (PLP), indicating phylogenetic relationships with amphibia. 3. Actinopterygian IP or teleostean 36k components were not detectable in lungfish CNS myelin. 4. The identical size of g-PLPs from Lepidosiren and Protopterus (Mr = 29,000) underlines the close relationship of the Lepidosirenidae. The smaller size of g-PLP from the ceratodidan Neoceratodus forsteri (Mr = 27,500) pointed to an earlier diversion.

Animals↗
PubMed1987

Comparison of intraperoxisomal localization form and properties of amphibian (Rana catesbeiana) uricase with those of other animal uricases.

Liver uricase of bull frog (Rana catesbeiana) was present as the soluble form in the peroxisomal matrix and consisted of four identical subunits with a molecular weight of 30,000. These properties were identical with those of fish liver uricase but differed from mammalian liver uricase. Purified uricase from the frog liver was insoluble in hypertonic, hypotonic and detergent solutions at pH 6-9. This insolubility was the same as mammalian liver uricase but differed from fish liver uricase; fish uricase was soluble in these solutions. The frog liver uricase did not cross-react immunologically with both uricases of fish and mammalian liver. An immunological cross-reactivity of liver uricase was observed among amphibia.

Animals↗
PubMed1987

Phytosphingosine is a characteristic component of the glycolipids in the vertebrate intestine.

Sphingoids in the intestinal lipids of an agnatha, a chondrichthyes, two osteichthyes, three amphibia, three reptiles and two avian species were analyzed by reversed phase high performance liquid chromatography. The glycolipid fraction of all the samples studied contained 4-D-hydroxysphinganine as the major component together with sphingosine and sphinganine. While the trihydroxy base was not found in their sphingomyelin fraction. The trihydroxy base was considered to be a characteristic component of the intestinal glycolipids for the vertebrates in general. Its concentration in the intestinal tissue had little correlation with the food habitat of the animals.

Animals↗
PubMed1987

The phylogenetic distribution of the liver protein F antigen.

F antigen is a liver protein of unknown function previously thought to be confined to class Mammalia. Using a recently developed radioimmunoassay, we show that F antigen can also be found in classes Aves, Reptilia, Amphibia and Osteichthyes. Ouchterlony gel diffusion (using murine antibodies) gave lines of identity or partial identity between mammalian F antigens, a line of identity between avian and reptilian F antigens (each showing partial identity to mammalian) and no precipitation with fish or amphibian F antigens. All immunopurified F antigens have molecular weights of 40,000-45,000.

Animals↗
PubMed1988

Isolation and partial characterization of IgM-like immunoglobulins from the serum of carp (Cyprinus carpio L.), frog (Rana ridibunda Pall.) and tortoise (Testudo graeca Pall.).

1. IgM-like immunoglobulin fractions have been isolated by combinations of precipitation procedures and gel-filtration from the serum of three vertebrate species, representative of the classes of Pisces (Cyprinus carpio L.), Amphibia (Rana ridibunda Pall.) and Reptilia (Testudo graeca Pall.). 2. The homogeneity of the isolated fractions has been confirmed electrophoretically and immunoelectrophoretically. 3. Electrophoretic mobility of IgM, similar for the three species studied has been observed in polyacrylamide gel; in agar gel immunoelectrophoresis carp and frog IgM mobilities are almost identical, in contrast to the markedly slower cathodic migration of tortoise IgM.

Animals↗
PubMed1991

Each otoconia polymorph has a protein unique to that polymorph.

1. Otoconia, contained within the vestibular portion of the inner ear, are mineralized by one of three polymorphs of calcium carbonate. Each otoconial polymorph contains a unique, major protein. 2. The major protein of calcitic otoconia of members of different vertebrate classes, Amphibia (African clawed frog) and Mammalia (rat), have similar molecular weights. 3. The major protein of calcitic rat otoconia and of vateritic otoconia of the gar may be calcium binding proteins. No protein from the other polymorph, aragonite, appear to have this characteristic.

Ambystoma mexicanum↗
PubMedDate not supplied

A comparative study of free radicals in vertebrates--I. Antioxidant enzymes.

1. Five antioxidant enzymes and cytochrome oxidase were measured in three vital organs of seven animal species of different vertebrate classes. 2. Minimal superoxide dismutase activities were found in the brain of homeotherms and in the lung of amphibia. Catalase (CAT) was maximal in liver and minimal in brain. 3. Possession of both Se dependent and independent glutathione peroxidase (GPx) is widespread in vertebrate organs. Similarities in tissue distribution were found among enzymes which use hydroperoxides (Se and non-Se GPx and CAT) or glutathione (both GPx and glutathione reductase) as substrates. 4. The results also suggest that the high aerobic capacity of the liver strongly influences the activities of the antioxidant enzymes in this tissue across vertebrate species, whereas other factors such as tissue pO2 can be more important in the lung.

Amphibians↗
PubMed1995

Comparative studies on NADP(+)-linked malic enzyme in the central nervous system of ectothermic and endothermic animals.

The maximum activity and intracellular distribution of NADP(+)-linked malic enzyme in brain of Mammalia, Aves, Reptilia, Amphibia and Pisces are reported. Malic enzyme activity was present in all animals brains investigated. Most of the enzyme activity was located in the mitochondrial fraction. In brain of endothermic animals the activity of malic enzyme was several-fold higher than in ectothermic animals. Other NADPH-producing enzymes (i.e. NADP(+)-linked isocitrate dehydrogenase and hexosemonophosphate shunt dehydrogenase) activities were essentially similar in all animals brains tested. However, the total potential capability of NADPH production was lower in ectothermic animals (due mainly to lower malic enzyme activity). It is suggested that the presence of NADP(+)-linked malic enzyme in the brain may be related mainly to mitochondrial metabolism, especially to maintain the mitochondrial pool of NADP+ in reduced form.

Animals↗
PubMed1994

Phylogenetic conservation of ganglioside GD3 expression during early vertebrate ontogeny.

Gangliosides were investigated in adult brains and in 5-vesicle stage embryos of representatives belonging to the four vertebrate classes: Chondrichthyes, Amphibia, Aves and Mammalia. Considerable variability in brain ganglioside composition and concentration was observed among the adult vertebrates. The ganglioside patterns of the developmentally matched vertebrate embryos were similar in that each comprised GD3 as the predominant ganglioside. The phylogenetic conservation of abundant GD3 expression during early vertebrate ontogeny is interpreted as biochemical evidence consistent with von Baer's theory of increasing differentiation and suggests that GD3 is of critical importance for normal vertebrate development.

Animals↗