Extracellular purine and pyrimidine nucleotides produce the biologic effects involved in activating P2 receptors.P2 receptors are divided P2X and P2Y receptor subtypes.There is molecular and functional evidence for widespread expression of P2X and P2Y receptor subtypes in osteoblasts,osteoclasts and cartilage cells of the skeletal system.Working through P2 receptors,ATP and other nucleotides released into the bone microenvironment regulate formation and activity of bone and cartilage,including development,growth,turnover and repair of biological functions.The release of nucleotides is increased under inflammatory conditions,and localized ATP release could stimulate formation and activation of osteoclasts.Abnormalities of bone remodelling can produce a variety of skeletal disorders.P2 receptors play an important role in the inflammatory disease of bone.

Aim To explore the modulaory effect of tetramethylpyrazine(TMP) on the responses mediated by P2X receptors.Methods Whole-cell patch-clamp technique was used to study the effects of TMP on P2X receptor agonists-activated currents in freshly isolated rat dorsal root ganglion(DRG) neurons.Results Extracellular application of ATP of 1 to 1000 ?mol?L~(-1) activated currents in DRG neurons(n=102).The ATP-activated currents showed rapid desensitization or slow desensitization.Preapplication of TMP(0.1～10 mmol?L~(-1))markedly inhibited ATP(100 ?mol?L~(1))-activated currents in the majority of the neurons examined(89.2%,91/102).TMP(1 mmol?L~(-1)) reduced ?,?-meATP(10 ?mol?L~(-1))-activated currents.TMP(1 mmol? L~(-1)) shifted the concentration-response curve of I_(ATP) downward markedly.TMP(1 mmol?L~(-1)) did not alter the reversal potential(0 mV) of ATP-activated currents.TMP(1 mmol?L~(-1)) significantly inhibited ATP(100 ?mol?L~(-1))-activated currents potentiated by PGE_2(100 ?mol?L~(-1))or SP(0.1 ?mol?L~(-1)).Intracellular application of 10 ?mol?L~(-1) H89(which is an inhibitor of PKA) reduced the inhibitory effect of TMP on ATP(100 ?mol?L~(-1))-activated currents.Conclusion The mechanism of TMP action may be the allosteric regulation via acting on PKA system and the large extracellular region of ATP receptor-ion channel complex(P2X receptors) to affect P2X receptor agonists-activated currents in rat DRG neurons.

P2 receptors activated by purine and pyrimidine nucleotides are divided into two subclasses:P2Y receptors which are G-protein coupled and P2X receptors which are ligand-gated ion channels.The expression of specific P2X and P2Y receptor subtypes in skeletal muscle cells has been demonstrated.Purinergic signaling plays an important role in muscle regeneration of muscular dystrophy,and is involved in skeletal muscle diseases such as muscular dystrophy,tendon inflammation and epilepsy,and provides the possibility of new therapeutic strategies for the treatment of muscle diseases.

Objective To observe the effects of tetramethylpyrazine (TMP) on acute nociception in rat hindpaw induced by purine 2X (P2X) receptor agonists, such as adenosine triphosphate (ATP) and ?, ?-meATP, prostaglandin E 2 (PGE 2), and substance P (SP). Methods The effects of TMP administered intraplantarlly on the acute nociception induced by P2X receptor agonists, PGE 2, or SP in the rat hindpaw were investigated by the method of the behavioral study. Results TMP (10 mmol/L) significantly depressed the acute nociception induced by ATP (1 ?mol/L) or ?, ?-meATP (0.6 ?mol/L) in the rat hindpaw. TMP (10 mmol/L) could inhibit the acute nociception induced by PGE 2 (5 ?mol/L) or ?, ?-meATP (0.2 ?mol/L) coinjected with PGE 2 (5 ?mol/L). TMP (10 mmol/L) could not affect the acute nociception induced by ?, ?-meATP (0.2 ?mol/L) coinjected with SP (10 ?mol/L). TMP could not obviously affect the inflammatory edema in rat hindpaw induced by the local administration of PGE 2, SP, or ?, ?-meATP coinjected with PGE 2 or SP individually. Conclusion The antinociceptive effects of TMP may mainly be associated with inhibiting the transmission of nociceptive information mediated by P2X receptor activation.

Objective Off-pump coronary artery bypass grafting (OPCAB) is used more widely in recent years in China. However, there is an argument on benefits and risks of off-pump surgery. Many studies shown that OPCAB had more benefits in short-term outcomes than conventional coronary artery bypass grafting(CCABG). But evidences from other studies suggested that OPCAB resulted in less long-term graft patency as compared with on-pump surgery. This study examined the longterm graft patency of OPCAB and CCABG performed by one surgeon. Methods 50 patients who had received surgical revascularization by a surgeon for more than 5 years were reviewed, 25 patients received conventional coronary artery bypass grafting ( group 1 ) and 25 patients received OPCAB ( group 2). All patients had angiograms for compareing the graft patency between the two groups. Results Among 25 patients in group 1,21 were male and 4 were female. The mean age of patients at surgery was (55.4 ±8.9) years. 15 cases had unstable angina, 16 patients had old myocardial infarction and 6 cases had diabetes.The ejection fraction (EF) was 0.58 ±0.14. The mean number of bypasses per patient was 3.32 ±0.63. Mean duration of operation was (3.58 ± 0. 82) hours. Mean follow-up duration was ( 86.52 ± 12.48) months. 83 grafts were evaluated for patency ( open vs. closed) and were graded by Fitzgibbon as grade A ( excellent graft), B ( impaired graft, with a stenosis of ≥50%, or a diameter less than 50% of the grafted artery), or O ( completely occluded). The graft patency was 73.49%, 61grafts were graded as Fitzgibbon A, 6 grafts as Fitzgibbon B and 16 grafts as Fitzgibbon 0. 25 patients were in group 2, 21males and 4 females. The mean age of patients at procedure was (58.2 ± 9.09) years, 11 patients had unstable angina, 13 patients had old myocardial infarction and 6 cases had diabetes. The ejection fraction (EF) was 0.59 ± 0. 14. Conclusion No 2011.03.013 difference in long-term graft patency was identified between on-pump and off-pump coronary artery bypass grafting. Off-pump oronary artery bypass grafting preformed by an experienced surgeon may gain similar long-term graft patency to that of conventional bypass.

Objective To investigate the role of P2X7 receptor in learning and memory dysfunction induced by HIV-1 enveloped protein gp120 in rats. Methods The imitating HIV-1 associated dementia (HAD) animal models were established by intracerebroventricular (ICV) infusion of gp120 in rats. The effect of gp120 on the learning and memory dysfunction in rats was evaluated by Morris water maze (MWM) test. The role of P2X7 receptor (P2X7R) was studied by Western blot and PCR assay. Results The ICV infusion of gp120 for 3 days in rats could imitated the HAD animal model. Results of MWM test showed that the rats in the model group had longer escape latencies and errors compared with those in the control group (P < 0.01); Results of Western blot and PCR assay showed that the expressions of P2X7R and P2X7 mRNA in hippocampus of rats in the model group were significantly increased (P < 0.01). Conclusions The ICV infusion of gp120 in rats could imitate the HIV-1 associated dementia (HAD) animal models, and P2X7R may be involved in the pathophysiological process of learning and memory dysfunction caused by gp120.

Objective This study aims to evaluate the initial results of a hybrid procedure for treating descending thoracic aortic disease that involves distal aortic arch.It also intends to report our initial experience in performing this procedure.Methods A total of 45 patients(35 males and 10 females) with descending thoracic aortic disease underwent a hybrid procedure,namely,thoracic endovascular aortic repair(TEVAR) combined with supra-arch branch vessel bypass,in our center from April 2009 to August 2014.Right axillary artery to left axillary artery bypass(n =20) or right axillary artery to left common carotid artery and left axillary artery bypass(n =25) were performed.The conditions of all patients were followed up from the 14th month to the 77th month postoperative[mean(38.0 ± 17.1) months].Mortality within 30 days,complications such as endoleak after the hybrid procedure,and stenosis or blockage of the bypass graft during the follow-up period were assessed.Results One case of death and one case of cerebral infarction were reported within 30 days.Two patients underwent open surgery beacuse of endoleak.And a newly formed intimal tear was observed in one patient and the patient underwent a second TEVAR during the follow-up period.Condusion Initial results suggest that the one-stage hybrid procedure is a suitable therapeutic option for thoracic aortic pathologies that involve distal aortic arch.However,this procedure is not recommended for type-B aortic dissection,in which a tear is located in the greater curvature or near the left subclavian artery,because of the high possibility of endoleak occurrence.

Aim To investigate effects of tetramethylpyrazine (TMP) on neuropathic pain induced by P2X_3 receptor. Methods Chronic constriction injury (CCI) model was adopted. Mechanical withdrawal threshold and thermal withdrawal latency were measured and P2X_3 immunoreactivity in L_4/L_5 spinal cord was detected by immunohistochemistry. Results At day 14 after operation, the mechanical withdrawal threshold and thermal withdrawal latency in group Ⅴ(CCI group) were lower than those in groupⅠ(NS group),Ⅱ(TMP group),Ⅲ(sham group) and Ⅳ (CCI+ TMP group)(P0.05). The expression of P2X_3 receptor in L_4/L_5 spinal cord of group Ⅳ was lower than that of group Ⅴ (P

Objective The optimal treatment for chronic type B dissection remains controversial. The purpose of this study was to report early and mid-term results of thoracic endovascular aortic repair (TEVAR) of chronic type B aortic dissection. Methods Methods From June 2001 to September 2007, 84 patients with chronic type B aortic dissection received TEVAR. The time between onset of dissection and TEVAR was (13.9 ± 22.0) months (ranged 1 - 120 months). All patients were followed for 6 - 86 months [mean (33.2 ± 19.2) months]. Results The entry tear was completely sealed in 77 cases ( 91.7% ) during TEVAR. The incidence of incomplete seal was 8.3%. One-month mortality was 1. 2%. One patient had retrograde type A dissection 1 month after operation. Four patients received a second TEVAR during follow-up :3 for endoleaking and 1 for newly formed intima tear. Seven patients (8.3%) died during follow-up: 3 thoracic aorta rupture due to endoleaking, 1 abdominal aorta rupture caused by continuous dilation of the abdominal aorta, unrelated to aortic dissection deaths in 2 and 1 died of unknown cause. The Kaplan Meier actuarial survival curve showed a 7-year survival rate of 84.4%. Conclusion Early and mid-term results showed that TEVAR was effective in treating chronic type B aortic dissection. Endoleak was the main cause of death during follow-up. With increasing of physician's experience and refinement of the stent-graft, results are likely to improve in the future.