Glutamine synthetase localization

Martinez-Hernandez, A., Bell, K. P. and Norenberg, M. D. Glutamine synthetase glial localization in rat brain. Science 195 1356-1358,1977. 

Martinez-Hernandez A, Bell KP, Norenberg MD (1977) Glutamine synthetase glial localization in brain. Science 195(4284) 1356-1358... 

Branjeon, J., Hirel, B. Forchioni, A. (1988). Immunogold localization of glutamine synthetase in soybean leaves, roots and nodules. Protoplasma 151, 88-97. 

Norenberg, M.D., and A.Martinez-Hernandez. 1979. Fine structural localization of glutamine synthetase in astrocytes of rat brain. Brain Res. 161(2) 303—310. 

Primary pulmonary diseases (e.g. primary pulmonary hypertension, pulmonary fibrosis, chronic obstructive respiratory diseases) cause chronic hepatic congestion due to chronic pulmonary heart disease, possibly leading to insufficiency. Hypoxaemia as a result of acute or chronic respiratory insufficiency can impair metabolic liver functions considerably. In 40—70% of patients with cirrhosis, hypoxaemia can be found in about 50% of cases with advanced cirrhosis, a reduced diffusion capacity for CO is detectable. Furthermore, pulmonary tissue contains a high level of glutamine synthetase, so that ammonia detoxification is possible (ultimately by perivenous hepatocytes) before the blood reaches the systemic circulation. In existing pulmonary diseases, localized ammonia detoxification is impaired. 

Takumi Y, Matsubara A, Danbolt NC, Laake JH, Storm-Mathisen J, Usami S, Shinkawa H, Ottersen OP (1997) Discrete cellular and subcellular localization of glutamine synthetase and the glutamate transporter GLAST in the rat vestibular end organ. Neuroscience 79 1137-1144. 

Quiz et al., 1979). Subcellular localization studies with barley indicate GSi to be localized in the cytosol while GSn is present in chloroplasts. Etiolated leaf tissue contained only GSi and glutamine synthetase of barley roots and seeds eluted as a single peak from DEAE-sephacel coincident with shoot GS. Suggesting GSj to be present in leaves, roots, and seeds while GSu is restricted to green tissues (Mann et al., 1980). 

Norenberg, M. D. and Martinez-Hemandez, A. (1979) Fine structural localization of glutamine synthetase in astrocytes of rat brain. Brain Res., 161, 303-310 Pentschew, A. and Garro, F. (1966) Lead encephalomyelopathy of the suckling rat and its implications on the porphyrinopathic nervous diseases. Acta Neuropathol, 6, 166-17S Phelan, P. and Regan, C. M. (1982) Developmental expression of glutamine synthetase activity in rat brain. Ir. ]. Med. Sci., 151, 403-404... 

Mammalian cells contain two carbamoyl phosphate synthetases the glutamine-dependent enzyme (CPSase II) which is part of CAD and an ammonia-dependent enzyme (CPSase /) which is localized in the mitochondrial matrix and which is used in urea and arginine biosynthesis. Under certain conditions (e.g., hyperammonemia), carbamoyl phosphate synthesized in the matrix by CPSase I may enter pyrimidine biosynthesis in the cytoplasm. 

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