OBJECTIVETo test the different contrctile responses of extracellular nucleotides, such as ATP, UTP and nucleotide uridine adenosine tetraphosphate (Up4A) in gastric longitudinal muscle (LM) and circular muscle (CM). Examined the effect of P2X and P2Y receptor antagonists (in this study, we used IP5I and suramin) and cyclooxygenase inhibitor (indomethacin) on Up4A induced contractile responses in LM and CM.

METHODSThe rats were sacrificed and the stomachs were opened to gain LM and CM. Using organ bath system to assess contrctile responses of smooth muscle.

RESULTSUp4A could induce contractile responses in both CM and LM, which were similar with ATP and UTP. IP5 did not attenuate Up4A could induce contractions in both LM and CM, but suramin and indomethacin significantly inhibited Up4A contraction in CM, but not in LM.

CONCLUSIONOur results suggest that extracellular nucleosides and their inhibitors induce different responses between LM and CM.

Adenosine Triphosphate ; pharmacology ; Animals ; Dinucleoside Phosphates ; pharmacology ; Indomethacin ; Muscle Contraction ; Muscle, Smooth ; physiology ; Nucleotides ; pharmacology ; Rats ; Suramin ; Uridine Triphosphate ; pharmacology

Angiotensin II ; metabolism ; Cisplatin ; adverse effects ; Humans ; Kidney ; drug effects ; Kidney Diseases ; chemically induced ; metabolism

OBJECTIVETo investigate the role of autophagy inhibitor chloroquine (CQ) in the proliferation of pulmonary arterial smooth muscle cells (PASMCs) in hypoxia conditions.

METHODSThe following groups in this study were set up: control group, hypoxia group, 50 micromol/L CQ + hypoxia group, 50 micromol/L CQ group. The viability of PASMCs in every group was detected by MTT assay. Autophagic vacuoles in the cells were observed by MDC staining. Protein expression of microtubule associated protein light chain 3 (LC3) was measured by Western blot. Migration of PASMCs was detected by wound healing assay.

RESULTSCompared with control group, no effect on the viability of PASMCs was observed treated by CQ alone. In 1% hypoxia group, cell viability increased significantly compared with that in control group. The number of autophagic vacuoles and the rate of cell migration and also protein expression of LC3-II were also markedly increased. Compared with hypoxia group, addition of CQ increased the number of autophagic vacuoles and the levels of LC3-II protein, but decreased the proliferation and migration of PASMCs.

CONCLUSIONHypoxia could activates autophagy and contributes to proliferation and migration of PASMCs, and autophagy inhibitor CQ could decrease the effect of hypoxia on PASMCs through inhibiting autophagy process.

Autophagy ; drug effects ; Cell Hypoxia ; Cell Movement ; Cell Survival ; Cells, Cultured ; Chloroquine ; pharmacology ; Humans ; Microtubule-Associated Proteins ; metabolism ; Myocytes, Smooth Muscle ; drug effects ; Pulmonary Artery ; cytology

OBJECTIVETo explore the working mechanism and age-related change of the conflict processing system of the frontal cortex.

METHODSFifteen normal elderly people and 15 youth were performed a modified Eriksen flanker paradigm, while event-related potential (ERPs), which include 32 systerm electroencephalography, reaction time and correct rate were recorded.

RESULTSThe elderly group showed a distinct effect of reaction time and effect of conflict in the respond level compared with the youth group. The elderly group had a longer time window of N380 and same amplitude as the youth group. Low resolution brain electromagnetic tomography (LORETA) showed the bilateral temporal lobe and the dorsolateral prefrontal cortex (especially right) were activated in the youth group, while the left temporal lobe, the left dorsolateral prefrontal cortex and left medial frontal gyrus were activated in the elderly group.

CONCLUSIONWhen conflict stimuli existed in the response level, old people showed frontal interference control hypofunction. N380 reflected the activation of the left dorsolateral prefrontal cortex and the left temporal lobe during response selection and executive control processing in older people.

Adolescent ; Aged ; Aging ; Electroencephalography ; Evoked Potentials ; Frontal Lobe ; physiology ; Humans ; Prefrontal Cortex ; physiology ; Reaction Time ; Temporal Lobe ; physiology

OBJECTIVETo study the selective dilatation effects of iptakalim (Ipt) on basilar and pulmonary arterioles, and endothelial cell function of these arterioles in hypoxic rats.

METHODSSD male rats were divided into 2 groups:control and hypoxic group fed in normobaric hypoxic environment (O2 7.8%, 8 h). Arteriole rings about (204 + 5) pm were isolated and the tension of hypoxic arterioles pre-contracted by 6 nmol/L endothelin-1 (ET-1) was observed with wire myograph system model (DMT 610 m). The relaxing response of hypoxic arterioles induced by different concentration of Ipt were detected and endothelial activity was also tested by acetylcholine.

RESULTS10(5) mol/L acetylcholine (ACh)-mediated vasodilatation of basilar and pulmonary arterioles was greatly reduced in the hypoxic group than those in control group (P < 0.05). Compared with normal group, a novel ATP-sensitive potassium channel opener Ipt at the concentration ranging from 10(-11) mol/L to 10(3) mol/L, caused stronger dose dependent vasodilatation on hypoxic pulmonary arterioles, and there was no significant difference between control and hypoxic basilar arterioles.

CONCLUSIONThe endothelial function of basilar and pulmonary arterioles was damaged under hypoxic state, and Ipt selectively increased dilatation effects on hypoxic pulmonary arterioles, but not on hypoxic basilar arterioles which could improve high altitude pulmonary edema pathological state and be the novel drug in the treatment of pulmonary hypertension.

Acetylcholine ; pharmacology ; Altitude ; Altitude Sickness ; physiopathology ; Animals ; Arterioles ; drug effects ; Dilatation ; Endothelin-1 ; pharmacology ; Hypoxia ; KATP Channels ; drug effects ; Male ; Propylamines ; pharmacology ; Rats ; Vasodilation ; Vasodilator Agents ; pharmacology

OBJECTIVETo analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications.

METHODSThe SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines.

RESULTSSAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P < 0.05). In the dynamic observation of drug resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years.

CONCLUSIONDrug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

Anti-Bacterial Agents ; pharmacology ; Drug Resistance, Multiple, Bacterial ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Staphylococcal Infections ; drug therapy ; Staphylococcus aureus ; drug effects

OBJECTIVEEndothelial apoptosis plays an important role in the initiation of atherosclerosis. It would be useful to clarify whether activation of non-neuronal muscarinic receptor (NNMR) could prevent endothelial apoptosis and atherosclerosis. We investigated the effects of NNMR activation on regulating rat aortic endothelial cells (RAECs) apoptosis induced by homocysteine, an independent risk factor of atherosclerosis, and further studied its molecular mechanism.

METHODSRAECs were incubated using homocysteine at the concentration of 2.7 mmol/L for 36 h. RAECs were also pre-treated with carbachol or arecoline to examine their effects. RT-PCR was used to assess changes in the gene expression related to cell apoptosis.

RESULTSIncubation of RAECs with homocysteine at the concentration of 2.7 mmol/L resulted in morphologic changes, such as cellular shrinkage, membrane blebbing, chromatin condensation and margination. These could be attenuated by pretreatment with carbachol and arecoline at the concentration of 10 micromol/L for 12 h. Homocysteine induced apoptosis in RAECs and the molecular mechanisms were associated with the regulation of fas, fas-L and caspase-8 in the death receptor pathway, bcl-2, bcl-xL and bax in the mitochondrial pathway, caspase-12 in the endoplasmic reticulum pathway and caspase-3, caspase-6 and p53 as downstream effectors. Carbachol and arecoline attenuated the effects of homocysteine on genes in the death receptor pathway, in the mitochondrial pathway and in the downstream pathway. Atropine could reverse all of the effects of arecoline.

CONCLUSIONActivation of NNMR by carbacol and arecoline inhibits homocysteine-induced endothelial cell apoptosis mainly through regulation of death receptor pathway, mitochondrial pathway and downstream effectors.

Animals ; Aorta ; cytology ; Apoptosis ; Apoptosis Regulatory Proteins ; metabolism ; Arecoline ; Carbachol ; Cell Cycle ; Endoplasmic Reticulum ; metabolism ; Endothelial Cells ; cytology ; drug effects ; Homocysteine ; adverse effects ; Mitochondria ; metabolism ; Rats ; Receptors, Muscarinic ; metabolism

OBJECTIVETo investigate the effects of endothelial microvesicles (EMVs) induced by calcium ionophore A23187 on H9c2 cardiomyocytes.

METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with 10 micromol/L A23187 for 30 min. EMVs from HUVECs were isolated by ultracentrifugation from the conditioned culture medium. EMVs were characterized using 1 and 2 microm latex beads and anti-PE-CD144 antibody by flow cytometry. For functional research, EMVs at different concentrations were cocultured with H9c2 cardiomyocytes for 6 h. Cell viability of H9c2 cells and the activity of LDH leaked from H9c2 cells were tested by colorimetry. Moreover, apoptosis of H9c2 cells was observed through Hoechst 33258 staining and tested by FITC-Annexin V/PI double staining.

RESULTSEMVs were induced by A23187 on HUVECs, and isolated by ultracentrifugation. We identified the membrane vesicles (< 1 microm) induced by A23187 were CD144 positive. In addition, the EMVs could significantly reduce the viability of H9c2 cells, and increase LDH leakage from H9c2 cells in a dose dependent manner (P < 0.05). Condensed nuclei could be observed with the increasing concentrations of EMVs through Hoechst 33258 staining. Furthermore, increased apoptosis rates of H9c2 cells could be assessed through FITC-Annexin V/PI double staining by flow cytometry.

CONCLUSIONMicrovesicles could be released from HUVECs after induced by A23187 through calcium influx, and these EMVs exerted a pro-apoptotic effect on H9c2 cells by induction of apoptosis.

Annexin A5 ; Apoptosis ; Calcimycin ; pharmacology ; Calcium ; metabolism ; Cell Line ; Cell Membrane ; drug effects ; Coculture Techniques ; Flow Cytometry ; Fluorescein-5-isothiocyanate ; analogs & derivatives ; Human Umbilical Vein Endothelial Cells ; Humans ; Myocytes, Cardiac ; drug effects ; Staining and Labeling

OBJECTIVETo study the relationship between serum testosterone levels and the plaque formation of the carotid artery in a population-based cohort of independently living healthy women above 60 years of age.

METHODSAnalysis of the healthy elders from a population-based cohort study in 9 communities of Beijing. Carotid intima-media thickness and atherosclerotic plaques were determined ultrasonographically. Serum testosterone levels were measured by immunoassay. The data were analyzed with ANOVA and logistic regression analysis.

RESULTSThere was an inverse correlation between testosterone and plaque formation in old females (P < 0.01), while no association was found in males. Female with testosterone levels in the lowest quartile (< 0.49 nmol/L) had more risk of plaque formation (OR = 3.805, P < 0.01) after adjusted with age and other traditional factors of atherosclerosis.

CONCLUSIONTestosterone concentrations are negatively associated with carotid artery atherosclerosis in old women in Beijing, experimental and prospective studies are needed to determine the possible therapeutic role of testosterone in atherosclerosis.

Aged ; Atherosclerosis ; blood ; Carotid Arteries ; pathology ; Carotid Intima-Media Thickness ; Carotid Stenosis ; blood ; Female ; Humans ; Male ; Prospective Studies ; Testosterone ; blood

Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is not clear. The most studied health adaptations in skeletal muscle response to endurance exercise are increased muscle glycogen level and insulin sensitivity, fiber type transformation toward oxidative myofibers, and increased mitochondrial content/function. Mitochondria are dynamic organelles in eukaryotic cells critical in physical performance and disease occurrence. The mitochondrial life cycle spans biogenesis, maintenance, and clearance. Exercise training may promote each of these processes and confer positive impacts on skeletal muscle contractile and metabolic functions. This review focused on the regulation of these processes by endurance exercise and discussed its potential benefits in health and disease. We presented evidence suggesting that exercise training potentiates not only the biogenesis of mitochondria but also the removal of old and unhealthy mitochondria through mitochondrial quality control.
Adaptation, Physiological ; Exercise ; Humans ; Mitochondria ; physiology ; Muscle Contraction ; Muscle, Skeletal ; physiology