Small conductance Ca 2+ activated potassium channels ( SK channels) are potassium selective , voltage independent, and Ca 2+ high sensitivity. SK channels are widely distributed in neurons. SK underlie the slow afterhyperpolarization , which regulate the fire of neurons by spike frequency adaptation. Three mammalian SK channels (SK 1, SK 2, SK 3) have been cloned . Ca 2+ , CaM and neurotransimitters involve in the gating of these channels. The changes of these channels may result in memory, neuromuscular disorder and schizophrenia.

AIM To study the effects of propafenone on Kv 4 2 and Kv4 3 potassium current. METHODS Whole cell patch clamp technique was used to record changes of Kv4 2 and Kv4 3 potassium currents. RESULTS ① Propafenone redu ced the amplitude of Kv4 2 and Kv4 3 currents, in a concentration-dependent, IC 50 was 10 3 and 71 ?mol?L -1 respectively. ② Propafenone inhibi ted Kv4 2 and Kv4 3 current inactivation, 10 ?mol?L -1 propafenone acce lerates Kv4 2 current inactivation constant from (38 9?2 1) ms to (9 9?1 8) ms; and shifted the steady state inactivation curves of Kv4 2 current to negative potentials. 100 ?mol?L -1 Propaf enone accelerates Kv4 3 current inactivation constant from (144 8?20 8) ms t o (18 5?2 8) ms; and shifted the steady state inactivation curves of Kv4 2 c urrent to negative potentials. ③ propafenone inhibited Kv4 2 and Kv4 3 curren t activation, 10 ?mol?L -1 propafenone shifted the steady state activati on curves of Kv4 2 current to negative potentials. 100 ?mol?L -1 propafe none shifted the steady state activation curves of Kv4 2 current to negative po tentials. CONCLUSION Propafenone, maybe, also exerts its effects via blocking Kv4 2 and Kv4 3 current to antiarrhythmia.

Objective To study the histocompatibility of tissue engineered skin with the observation of the effects of selectins E and P on the immunological rejection after skin allograft in rats. Methods Tissue engineered skin was prepared as follows: The materials obtained from the neonatal SD rats were cultured and then grafted onto the adult Wistar rats. The expression of selectins E and P in the grafted skin was determined with immunohistochemical staining. Results The expression of selectins E and P was significantly higher in the rats with allograft than in the rats with the grafts of tissue-engineered material. Conclusion Selectins E and P play an important role in the immunological rejection after allograft of skin but the tissue-engineered skin graft possesses favorable histocompatibility and shows no obvious immunological rejection.

AIM To study the effects of H 2O 2 on transient outward potassium current METHODS Whole cell patch clamp technique was used to record changes of I A in the cultured rat hippocampal neurons RESULTS After exposure to 30 ?mol?L -1 H 2O 2 for 12 h (1) decreased I A current density from (53 8?15 8) PA?PF -1 to (18 5?6 2) PA?PF -1 ( n=10,P

left ventricle=cerebral cortex =urinary bladder smooth muscle. CONCLUSION mRNA expression levels of Kir2 1 and Kir3 1 in different tissues were different, this different expressions have physiological significance.

Objective To investigate the value of diffusion weighted magnetie resonance imaging and apparent diffusion coefficient (ADC) value in the diagnosis of pancreatic cancer.MethodsThe clinical data of 36 patients with pancreatie cancer who were admitted to the Wuxi No.2 People's Hospital from March 2009 to June 2011 were retrospectively analyzed,and the clinical data of 30 healthy volunteers were collected.All candidates received diffusion weighted magnetie resonance imaging examination.The signal intensity ratios ( SIRs ) of the cancer and the pericancerous tissues in the T1 weighted-images (T1WI),T2 weighted-images (T2WI)and diffusion weighted-images (DWI) were compared by using one-way analysis of variance.The ADC values of the cancer and the paricancerous tissues were compared using the paired t test.The differences of the ADC values of the cancer and pericancerous tissues compared with those of healthy individuals were analyzed using an independent sample t test.ResultsThe accuracy rate of preoperative magnetic resonance imaging examination was 92％.The relative SIRs were 0.203 ± 0.190 in the T2 WI,0.399 ± 0.201 in the T1 WI and 0.579 ± 0.291 in the DWI,respectively,with no significant differences across the 3 kinds of images (F=5.92,6.15,6.83,P ＜ 0.05 ),while SIRs of the T1 WI and DWI were significantly higher than that of the T2 WI ( P ＜ 0.05 ).There was no significant difference in SIRs when comparing T1 WI and DWI ( P ＞ 0.05 ).The mean ADC values of the cancer and pericancerous tissues of the pancreatic cancer patients and the pancreatic tissues of healthy individuals were (1.40±0.24) ×10 3 mm2/s,(1.71 ±0.10) ×10-3 mm2/s and (1.73±0.30) ×10-3 mm2/s,respectively,with significant differences across the 3 modes of images (t =10.54,12.08,P ＜ 0.05).ConclusionDWI can show high quality images of the lesions,and ADC value is helpful in the diagnosis of pancreatic cancer.

Objective To investigate the effect of tramadol combined with sufentanil on postop-erative analgesia in patients received upper-abdominal surgery.Methods One hundred and fifty pa-tients scheduled for selective upper-abdominal operation were randomly divided into five groups (n=30 each):Tramadol group (T);large dose sufentanil combined small dose tramadol group (TS1 );balanced tramadol and sufentani group (TS2 );small dose sufentanil combied large dose tramadol group (TS3);sufentanil group (S).Postoprative VAS scores were recorded respectively at 1,4,8, 12,24,36,48 h when be in quiet and turning 90 degree,Ramsay sedation score,analgesia pump pressing times and side effects were also recorded.Results VAS scores in group TS2,group TS3 and group S at each time point both be in quiet and turning 90 degree were significantly lower than that of group T and group TS1 (P <0.05).Group S sedation score significantly higher than group T (P <0.05).No significant difference in other groups.Conclusion Balanced tramadol and sufentanil group has best analgesic effect and least side effects.With the increasing doses of sufentanil,its analgesic effect was not obvious enhancement.

Objective To study the changes of biochemistry indexes in blood serum and bone mineral density (BMD) of secondary osteoporosis after spinal cord injury (SCI) in rats. Methods 120 male Wistar rats were divided randomly into 12 groups (n=10). The rats in control groups were only removed larmina with dura intact, without spinal cord injury at the level of the tenth thoracic vertebrae, the rats in experimental groups were also removed larmina, then paraplegic model was made by the method of Allen's (60gcm). The changes of biochemistry indexes in blood serum and BMD were observed. Results Compared with control groups, the concentrations of alkaline phophatase (ALP) were decreased at the 1st and the 3rd week in experimental groups (P0.05). BMD of tibia was decreased at the 7th and 11th week in experimental group (P

Objective:To study the effects of different collagen conc en tration on the proliferation of rat fibroblasts.Methods: Fibrobl asts of 1-2 days new born SD rat from back skin were isolated and seeded into D MEM containing ?=10% fetal boven serum and collagen at the concentration (mg/ml ) of 6.4,5.3and 4.0 respectively. The status and numbers of fibroblasts were observed under light microscope and analysized using ttest. Results : The general condition of fibroblasts in 6.4 mg/ml collagen was better than that in the other groups. The processes of the cells were apparent, simila r to the status of the cells in two-dimensional culture. Vacuoles and granules in cells were observed in 5.3 mg/ml collagen. In 4 mg/ml collagen, the processe s of fibroblasts disappeared; the nuclei were karyopyknosis or dissolved. Some c ells was likely to be apoptotic. The average cell number per 200? field of micr oscope in 6.4,5.3 and 4.0 mg/ml collagen was 25,15 and 6 respectively (P