ABSTRACT
<p><b>OBJECTIVE</b>To investigate the role of extracellular signal-regulated kinase1/2 (ERK1/2) pathway in the regulation of aquaporin 4 (AQP4) expression in cultured astrocytes after scratch-injury.</p><p><b>METHODS</b>The scratch-injury model was produced in cultured astrocytes of rat by a 10-μL plastic pipette tip. The morphological changes of astrocytes and lactate dehydrogenase (LDH) leakages were observed to assess the degree of scratch-injury. AQP4 expression was detected by immunofluorescence staining and Western blot, and phosphorylated-ERK1/2 (p-ERK1/2) expression was determined by Western blot. To explore the effect of ERK1/2 pathway on AQP4 expression in scratch-injured astrocytes, 10 µmol/L U0126 (ERK1/2 inhibitor) was incubated in the medium at 30 min before the scratch-injury in some groups.</p><p><b>RESULTS</b>Increases in LDH leakage were observed at 1, 12, and 24 h after scratch-injury, and AQP4 expression was reduced simultaneously. Decrease in AQP4 expression was associated with a significant increase in ERK1/2 activation. Furthermore, pretreatment with U0126 blocked both ERK1/2 activation and decrease in AQP4 expression induced by scratch-injury.</p><p><b>CONCLUSION</b>These results indicate that ERK1/2 pathway down-regulates AQP4 expression in scratch-injured astrocytes, and ERK1/2 pathway might be a novel therapeutic target in reversing the effects of astrocytes that contribute to traumatic brain edema.</p>
Subject(s)
Animals , Rats , Aquaporin 4 , Metabolism , Astrocytes , Metabolism , Butadienes , Cells, Cultured , Down-Regulation , Enzyme Activation , Extracellular Signal-Regulated MAP Kinases , Metabolism , MAP Kinase Signaling System , Nitriles , Rats, Wistar , Skin , Wounds and InjuriesABSTRACT
<p><b>OBJECTIVE</b>To study the changes in endogenous neuregulin-1 (Nrg1) expression in the anterior pituitary of female Wistar-Furth rats in different phases of the estrous cycle.</p><p><b>METHODS</b>Female Wistar-Furth rats during estrous cycles were used. RT-PCR was employed to study the changes in the expression of Nrg1 isoforms and their cognate receptors ErbB-2 and ErbB-4 in the anterior pituitary in different phases of the estrous cycle. Western blotting was used to detect Nrg1 expression at the protein level. Immunofluorescence staining was used to identify hypophyseal cells expressing Nrg1 and observe the localization and distribution of Nrg1 and functional phosphorylation of ErbB-4. The co-expression of Nrg1 and ErbB-4 in the anterior pituitary of Rhesus monkey was also investigated.</p><p><b>RESULTS</b>Some of the Nrg1 isoforms, especially type III Nrg1s, were expressed at a higher level during the estrous cycle I (E1) and estrous cycle II (E2), a result consistent with that of Western blotting for samples of the anterior pituitaries collected at these phases. Immunofluorescence staining identified the gonadotrophs as the main source of Nrg1, and showed an extensive distribution of Nrg1 in the anterior pituitary in E1 and E2 phases accompanied by apparent phosphorylated activation of ErbB-4. Adjacent distribution of Nrg1- and ErbB-4-positive cells was also observed in the anterior pituitary of male Rhesus monkeys.</p><p><b>CONCLUSION</b>Our results provide evidence for the expression of multiple Nrg1 isoforms and the presence of Nrg1/ErbB-4 signaling in the anterior pituitary of female Wistar-Furth rats. This signaling demonstrates an estrous cycle phase-related pattern. Additionally, Nrg1/ErbB-4-based juxtacrine signaling may exist in the anterior pituitary of male non-human primate.</p>
Subject(s)
Animals , Female , Male , Rats , Estrous Cycle , Physiology , Macaca mulatta , Neuregulin-1 , Metabolism , Phosphorylation , Pituitary Gland , Metabolism , Protein Isoforms , Metabolism , Rats, Inbred WF , ErbB Receptors , Metabolism , Receptor, ErbB-4ABSTRACT
Aim The study is to observe the clinical efficacy of losartan in hypertentive patientswith left ventricular hypertrophy. Methods 21 case were given losartan for 20 wk and 24h ambulatory blood pressure monitoring and color doppler echocardiography were per-formed in the patients before and after treatment.Results The 24 h SBP, 24 h DBP,dDBP, nSBP were from (151 ? 15) 、(93 ?9)、(155 ? 15)、(96 ? 10)、(146 ? 16)、(88 ? 11)mmHg before treatment to (132 ? 11)、(82 ? 8)、(137 ? 12)、(88 ? 9)、(120 ? 9)、(120 ? 15)、(74 ? 9) mmHg after treatment respectively and the IVST, PWT and LVMI were from(14.2 ? 1 .5) mm、(13. 9 ? 1. 45) mm、(152. 1 ? 24. 2) g? m2-1 BSA before treatment to(12. 1 ? 1. 31) mm、 (12. 2 ? 1. 41) mm、(130. 6 ? 23. 1) g? m2-1 BSA after treatment re-spectively. All the parameters after treatment in the patients were significantly decreased ascompared with those before treatment (P