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Parkinson's disease is characterized by progressive cell death in the substantia nigra pars compacta, which leads to dopamine depletion in the striatum and indirectly to cortical dysfunction. Increased glutamatergic transmission in the basal ganglia is implicated in the pathophysiology of Parkinson's disease and glutamate receptor mediated excitotoxicity has been suggested to be one of the possible causes of the neuronal degeneration. In the present study, the effects of serotonin, gamma-aminobutyric acid and bone marrow cells infused intranigrally to substantia nigra individually and in combination on unilateral 6-hydroxydopamine induced Parkinson's rat model was analyzed. Scatchard analysis of total glutamate and NMDA receptor binding parameters showed a significant increase in Bmax (P < 0.001) in the cerebral cortex of 6-hydroxydopamine infused rat compared to control. Real Time PCR amplification of NMDA2B, mGluR5, bax, and ubiquitin carboxy-terminal hydrolase were up regulated in cerebral cortex of 6-hydroxydopamine infused rats compared to control. Gene expression studies of GLAST, ά-Synuclien and Cyclic AMP response element-binding protein showed a significant (P < 0.001) down regulation in 6-OHDA infused rats compared to control. Behavioural studies were carried out to confirm the biochemical and molecular studies. Serotonin and GABA along with bone marrow cells in combination showed reversal of glutamate receptors and behaviour abnormality shown in the Parkinson's rat model. The therapeutic significance in Parkinson's disease is of prominence.  相似文献   
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Philip L Hooper 《Trials》2001,2(6):251-3
An explanation for the higher incidence of cardiovascular disease and heart failure in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) with doxazosin and the Vasodilator Heart Failure Trial (V-HeFT) with prazosin might be decreased expression of heat shock proteins. Heat shock proteins help to protect cells from ischemic injury by decreasing oxidation, suppressing cytokine action, refolding damaged proteins, and decreasing apoptosis. I hypothesize that α-adrenergic blockade decreases heat shock protein levels, thus making the heart and vascular system vulnerable to injury from pathologic processes such as ischemia, hypertension, oxidation or inflammation. Similarly, poor cardiovascular outcomes with calcium-channel blockers might be due to decreased expression of heat shock proteins.  相似文献   
927.
Homotypic and heterotypic permeable junction formation between a metabolic cooperationdefective embryonal carcinoma variant R5/3 and its parent PC13TG8 have been studied by uridine prelabelling. The results indicate that the lesion results not in a modified specificity of cell recognition but in a deficiency in forming permeable junctions irrespective of contiguous cell type. New techniques have been developed for the study of intercellular transfer of sodium ions and of amino acids of the urea cycle. These have been used to demonstrate that the R5/3 lesion reduces the capacity of the cells to participate in intercellular transfer of three unrelated categories of small molecule.  相似文献   
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Although earlier North American records of Stictyosiphon soriferus (Reinke) Rosenvinge cannot he substantiated, the species is shown to be common in Newfoundland and is also reported from Nova Scotia. Plants are summer annuals and a component of ephemeral subtidal communities characteristic of suitable inlets and harbors. Only plurilocular reproductive organs are produced. In culture the life history of populations from both sides of the North Atlantic consists of a direct replication by asexual zoospores. A microscopic stage might occur in the field, and is presently known only from European cultures. In eastern Canada S. soriferus is readily distinguishable from S. tortilis (Rupr.) Reinke, S. subsimplex Holden and S. griffithsianus (Le Jol.) Holmes & Batters.  相似文献   
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1. Hypothalami from pregnant and non-pregnant rabbits were homogenized in sucrose and separated into fractions by differential and density-gradient centrifugation. 2. The fractions were examined for enzymes capable of inactivating oxytocin. 3. Enzyme activity was detected in the supernatant and one particulate fraction of both pregnant and non-pregnant animals. 4. The specific activity of the enzymes increased during early pregnancy, and coincided with the time of blastocyst spacing and implantation in the uterus.  相似文献   
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