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Objective To observe the expression of acid-sensing ion channel la (ASICla) and to investigate the effect of intracellular Ca2 + concentration on focal cerebral ischemia in diabetic rats.Methods 108 male Wistar rats were divided into three groups:group A [rats with middle cerebral artery occlusion (MCAO)],group B [rats with MCAO and diabetes (DM + MCAO)],group C [rats with MCAO and diabetes treated with fasudil intervention (DM+ MCAO+ fasudil)] (n=36 each).Samples were obtained at the time points of 1,3,6 and 24 h after ischemia respectively (n=9).Models of MCAO and DM+MCAO were prepared.Rats in DM+MCAO+Fasudil group were treated with fasudil 1 mg/Kg by caudal vein injection after half an hour when DM+MCAO model successfully prepared.ASICla expressions were detected at different time points of ischemia in the 3 groups respectively.Ca2+ concentration in ischemia cortex cells were determined at different time points of ischemia in group B and C.Results ASICla expressions were gradually increased along with the ischemia time in group A and B (group A:0.71±0.10,0.80±0.11,0.86±0.08,0.93±0.09;groupB:0.86±0.11,1.05±0.51,2.42±0.08,2.78±0.04; all P＜ 0.05),and ASICla expressions at different time points were higher in group B than in group A (all P＜ 0.05).Ca2-concentration were gradually increased along with the ischemia time in group B (106.32± 18.6,137.84±14.32,151.94± 18.38,183.61±7.96,all P＜0.05).Compared with group B,the levels of ASICla expression and calcium current were reduced in group C.Conclusions The activation of ASICla increases calcium ion flow internal pathway leading to intracellular calcium overload,which may be one of the reasons for the aggravation of focal cerebral ischemia in diabetes.
RESUMO
<p><b>OBJECTIVE</b>To explore the isolation, purification and expansion of human umbilical cord blood mesenchymal stem cells (MSCs) into neuron-like cells in vitro.</p><p><b>METHODS</b>Human cord blood samples were obtained sterilely with 20 U/ml preservative-free heparin. MSCs were isolated by lymphocyte separation medium (density 1.077 g/ml), and purified and expanded with Mesencult trade mark medium. The surface antigen expression of MSCs was detected by flow cytometry. The passage 2, 5 and 8 of the expanded MSCs were induced to differentiate to neuron-like cells. Specific markers and structures were detected by immunohistochemistry and histochemistry methods.</p><p><b>RESULTS</b>The number of MSCs increased two- to three-fold with each expanded passage. 6.6 x 10(5) primary MSCs were expanded ten passages to reach a number of 9.9 x 10(8), and was increased about 1.5 x 10(3)-fold. Flow cytometry showed that MSCs did not express antigens CD(34), CD(11a) and CD(11b), but expressed strongly CD(29) and weakly CD(71), which was identical to human bone marrow-derived MSCs. 70% cells exhibited typical neuron-like phenotype after induction. Immunohistochemistry staining showed that all of the induced different-passage MSCs expressed neurofilament (NF) and neuron-specific enolase (NSE). Special Nissl body was found by histochemistry.</p><p><b>CONCLUSION</b>MSCs in human umbilical cord blood can expand in vitro and differentiate into non-mesenchymal cells.</p>