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.

Objective To investigate the changes of serum bilirubin level in elderly patients with acute cerebral infarction and its significance.Methods 164 hospitalized elderly patients,who suffered from acute cerebral infarction within 1 week after onset,were divided into 2 groups according to age:group A aged over 60 years(n=85) and group B aged 40-60 years(n=79),and 66 healthy subjects aged over 40 years were collected as controls(group C).Serum bilirubin levels in all subjects were determined.The ratio of pulse pressure over mean arterial pressure(PP/MAP) in group A and B was calculated.Nerve function scores in the three groups were detected before and after 2 weeks of treatment.Meanwhile,the data of risk factors including blood glucose,blood pressure,blood lipids,smoking and drinking in group A and B were collected.Results Compared with group C,serum total,direct,indirect bilirubin levels were increased in group A and B(both P＜0.01),and the change was smaller in group A than in group B(P＜0.05).The nerve function scores was lower in group A than in group B before and after treatment [(35.2±12.6) vs.(44.3±7.9),(40.7±9.1) vs.(51.3± 4.1),t=5.58,9.73,both P＜0.01],but PP/MAP and the numbers of risk factors were higher in group A than in group B [(0.46±0.06) vs.(0.38±0.06),93.01 vs.71.20,both P＜0.01].There were no significant correlations of serum total,direct and indirect bilirubin levels with nerve function scores in group A or B(all P＞0.05).Conclusions Serum bilirubin level is increased in patients with acute cerebral infarction,but the endogenous antioxidant capacity is decreased because of aging,multiple risk factors and more serious atherosclerosis in elderly patients,and the increment of bilirubin level is relatively smaller in acute cerebral ischemia,leading to the reduced protective effect against stress.Serum bilirubin level may influence the prognosis in patients with acute cerebral infarction.