BACKGROUND: Studies confirm that ischemia/reperfusion (I/R) injury can induce myocardial apoptosis. The loss of mitochondrial membrane potential (MMP) after reperfusion is the inevitable pathway of apoptosis. Protection of MMP may reduce apoptosis.OBJECTIVE: To observe the effect of naloxone on MMP of hypoxic myocardial cells and apoptosis in neonatal rats, and investigate the protective effect of naloxone on hypoxic myocardial cells.DESIGN: Observation and controlled trial.SETTING: Department of Cardiology, the General Hospital of Chinese PLA.MATERIALS: Detection of apoptosis of myocardial cells was carried out in the Laboratory of Pathophysiology, General Hospital of Chinese PLA in December 2004. Ten neonatal rats were used, and detection of MMP of myocardial cells was carried out in the same laboratory in March 2006 and 20 rats were used. All the involved rats were provided by the Animal Center of the General Hospital of Chinese PLA on the day of birth, were involved in this trial. Reagents: Naloxone hydrochloride injection (0.4 g/L, Beijing Sihuan Pharmaceutical Factory, Batch No. 0206272); the lowest and essential medium (Dulbecco, DEME,GIBCO company); phosphate buffer solution and fetal bovine serum (PBS and FBS, SIGMA Company).METHODS: The neonate rats were cut open along the median line of chest bone after local sterilization with iodine tincture on the day of birth. 1/3 ventricular myocardium before cardiac apex was harvested. On the 4th day of the culture,culture flasks of cells in good growth status ( ＞ 106 cells/bottle) were selected and divided into 3 groups: control group (normal culture, n =3 bottles), hypoxia group (hypoxia/reoxygenation, n =15 bottles) and naloxone group (hypoxia/reoxygenation, and treated by naloxone, n =15 bottles). Three time points were set in hypoxia group and naloxone group according to different time of hypoxia and reoxygenation: hypoxia 2 hours/reoxygenation 0 hour; hypoxia 2 hours/reoxygenation 2 hours; hypoxia 2 hours/reoxygenation 4 hours, 5 bottles at each time point. In the hypoxia group, DEME medium, which was pre-filled with 0.95 volume fraction of N2 and 0.05 volume fraction of CO2, containing 0.01 volume fraction of FBS, was used and 0.95 volume fraction of N2 and 0.05 volume fraction of CO2 was also filled to replace the air in the culture flasks. The culture flasks were enveloped for incubation at 37 ℃. The cells in the hypoxia group were incubated at normal condition (0.95 volume fraction of air and 0.05 volume fraction of CO2) at set time. In the naxolone group, hypoxia/reoxygenation treatment was the same as above, and naloxone hydrochloride was added at the sametime and the final concentration of naloxone in culture flasks was 5 μmol/L (The volume for naloxone ≤ 0.5% of the total medium). In the control group, hypoxia/reoxygenation and naloxone treatment were not given, but the same volume of normal saline was added, and this time served as time point of hypoxia 0 hour/reoxygenation 0 hour. After intervention,myocardial MMP changes and apoptosis were detected with fluorescent staining-flow cytometer at different time after hypoxia/reoxygenation.MAIN OUTCOME MEASURES: ① MMP changes of hypoxia group and naloxone group at different time points; ② Comparison of survival, apoptosis and necrosis of cells at hypoxia 2 hours/reoxygenation 4 hours in each group.RESULTS: ① After hypoxia, MMPs of the cells in hypoxia group and naloxone group were decreased. MMP of the cells in the naloxone group was higher than that in the hypoxia group at each time point (P ＜ 0.01). The great amplitude of decrease of MMP occurred in hypoxia period, but not in reoxygenation period. ② At hypoxia 2 hours/reoxygenation 4 hours, the apoptotic and necrotic rates in the hypoxia group were significantly higher than those in the naloxone group [(9.88±0.98)% vs. (2.41±0.52)%; (5.10±0.29)% vs. (3.56±0.56)%, both P ＜ 0.01]. The apoptotic rate was significantly higher than the necrotic rate in the hypoxia group (P ＜ 0.05).CONCLUSION: Early application of naloxone can significantly alleviate and postpone the decrease of myocardial MMP after I/R, and reduce apoptosis and necrosis.

AIM To determine the effect of isoflurane(Iso) on pulmonary surfactant(PS) synthesis in cultured primary ATⅡ cells. METHODS ATⅡ cells were isolated from adult rat lungs and used for the experiments after 32 h in primary culture. Iso 0.28 and 2 8 mmol?L -1 was added into the media of normal and H 2O 2 (75 ?mol?L -1 )-treated cells, and the cells were further incubated for 2 h. The cell proliferation was measured with MTT method and PS synthesis with 3H-choline chloride incorporation. RESULTS Iso had no effect on the proliferation of ATⅡ cells, but markedly decreased PS synthesis in normal alveolar type Ⅱ cells, and aggravated the decrease of PS synthesis induced by H 2O 2. CONCLUSION Iso may decrease PS synthesis of alveolar type Ⅱ cells in vitro , and aggravate the damage of the cells under peroxidation condition.

On the basis of superimposed stenosis, a model of femoral occlusive thrombus was produced in 12 dogs. Among them, urokinase+saline were given in 6 dogs (group A), aptamer was given ten minutes before urokinase in another 6(group B). The aim of the study was to explore the effect of a new direct sited thrombin inhibitor thrombin aptamer on thrombolysis . The results showed that the interval between thrombosis and reflow was significantly different between this two groups ( P

DynaPulse, a newly developed noninvasive apparatus, is valuable in assessing blood pressure, cardiac output and vascular compliance. The purpose of the present study was to evaluate the validity of cardiac output measurement using DynaPulse in patients, compared with echocardiography and Fick method. Forty five inpatients underwent cardiac output measurement using DynaPulse (CO DP ) and Doppler echocardiography (CO DE ), cardiac output was measured with DynaPulse (CO DP ) and Fick method (CO FM ) in additional 26 patients. A good correlation was found between CO DP and CO DE ( r =0 76). There was an acceptable correlation between CO DP and CO FM ( r =0 61). DynaPulse can provide a noninvasive, clinically useful estimation of cardiac output.

To explore the changes of mitochondrial membrane potential in rat cadiomyocyte apoptosis by fluorescent JC 1, H 2 O 2 was used to induce cadiomyocyte apoptosis, and JC 1 in combination with flow cyometry was used to detect the changes of mitochondrial membrane potential in the early stage of cadiomyocyte apoptosis. The results showed that living cardiomyocytes had a high mitochondrial membrane potential, JC 1 aggregates were formed in the inner membrane of mitochondria and emitted orange red fluorescence. H 2 O 2 caused the decrease of mitochondrial membrane potential, JC 1 aggregates were dissociated to monomer,which emitted green fluorenscence. So the red fluorescence decreased. It is suggested that JC 1 in combination with flow cyometry is an ideal method to detect the changes of mitochondrial membrane potential.

Objective To compare and assess the antihypertentive efficacy and safety of barnidipine hydrochloride and felodipine in the elderly hypertentive patients. Methods 69 elderly patients(60-75 years old ) with mild or moderate essential hypertension were selected and randomly assigned to two groups, one was medicated with barnidipine (36 patients) and another (33 patients) with felodipine. Placeboes were given for 2 weeks, then the testees were administered barnidipine 10mg/d or felodipine 5mg/d for 2 weeks, followed by an increased administration of dose titration to barnidipine 15mg/d or felodipine 10mg/d for another 2 weeks in those patients with DBP≥90mmHg. Both groups were administered once daily. Results After 4 weeks administration no statistical difference was found on the total effectiveness between barnidipine and felodipine groups (100.0% vs 93.9%). Both SBP and DBP declined by 20.7?7.8mmHg and 17.6?4.5mmHg respectively in barnidipine group, and 20.2?9.6mmHg and 17.6?6.1mmHg respectively in felodipine group. The decline of blood pressure showed no significant difference between the two groups. The mild harmful respond occurred in 4 of 36 patients of barnidipine group (11.1%), and in 3 of 33 patients of felodipine group(9.1%).Conclusion The results suggested that barnidipine is effective and well tolerated in antihypertension of the old patients.

Objective To explore the effect of isoflurane on Na-K-ATPase activity in cultured primary alveolar type Ⅱ(ATⅡ) cells with or without being injured by H 2O 2.Methods ATⅡcells were isolated from adult rat lungs and incubated for 24h and divided into six groups. Group 1 served as control and received no treatment. Group 2 and 3 ATⅡ cells were exposed to 0.28 or 2.8mmol/L isoflurane. In group 4 cells were exposed to 75?mol/L H 2O 2. In group 5 and 6 cells were exposed to both 75?mol/L H 2O 2 + 0.28 or 2.8mmol/L isoflurane. Each group was incubated for another 2h after the addition of isoflurane and /or H 2O 2. The Na-K-ATPase activity of ATⅡcells ,the LDH activity and the MDA concentration of fluid culture medium were measured by biochemical methods.Results Isoflurane markedly decreased Na-K-ATPase activity in normal ATⅡ cells, but aggravated the decrease in Na-K-ATPase activity induced by H 2O 2. Isoflurane had no effect on LHD activity and MDA concentration of fluid culture medium of normal ATⅡ cells ,but significantly increased LHD activity and the MDA concentration of of fluid culture medium of ATⅡ cells injured by H 2O 2.Conclusions Isoflurane can inhibit Na-K-ATPase activity of ATⅡ cells in vitro, and aggravate the damage of ATⅡ cells caused by oxidants.

Peripheral nerve injury of a limb usually causes functional reorganization of the contralateral somatosensory cortex.However, the patients with an operation of the contralateral seventh cervical nerve (C7) transfer to an injured arm with brachial plexusroot avulsions usually have the sole tactile sensibility of the healthy hand when the injured hand is touched at the early stage after theoperation. Then, at later stage they gradually get normal sense from the injured and the normal hands independently. Mimicked theprocess in a rat model based on the above operation, representations of the injured forepaw and the healthy forepaw in thesomatosensory cortex were studied by means of somatosensory evoked potential (SEP) recording. Somatosensory function shown inSEP response amplitude and peak latency of the injured forepaw gradually recovered with time after the operation due to thecontralateral C7 regeneration toward the injured limb, accompanied with the recovery process of limb movement. The somatosensoryrepresentation of the injured forepaw was observed exclusively in the ipsilateral somatosensory cortex since the 5th month after theoperation. Accordingly, the overlapped representation of the injured and healthy forepaws emerged in the ipsilateral somatosensorycortex of 13 rats studied except one with separated representation though the SEP latency and response amplitude were different inresponding to stimuli on the two forepaws. It is concluded that the contralateral peripheral nerve transfer to the injured arm can causedynamically functional reorganization in the ipsilateral somatosensory cortex suggesting a remarkable plasticity of the brain functioninduced by an alteration of sensory input between two sides of the body in adult rats.

Peripheral nerve injury of a limb usually causes functional reorganization of the contralateral somatosensory cortex.However, the patients with an operation of the contralateral seventh cervical nerve (C7) transfer to an injured arm with brachial plexus root avulsions usually have the sole tactile sensibility of the healthy hand when the injured hand is touched at the early stage after the operation. Then, at later stage they gradually get normal sense from the injured and the normal hands independently. Mimicked the process in a rat model based on the above operation, representations of the injured forepaw and the healthy forepaw in the somatosensory cortex were studied by means of somatosensory evoked potential (SEP) recording. Somatosensory function shown in SEP response amplitude and peak latency of the injured forepaw gradually recovered with time after the operation due to the contralateral C7 regeneration toward the injured limb, accompanied with the recovery process of limb movement. The somatosensory representation of the injured forepaw was observed exclusively in the ipsilateral somatosensory cortex since the 5th month after the operation. Accordingly, the overlapped representation of the injured and healthy forepaws emerged in the ipsilateral somatosensory cortex of 13 rats studied except one with separated representation though the SEP latency and response amplitude were different in responding to stimuli on the two forepaws. It is concluded that the contralateral peripheral nerve transfer to the injured arm can cause dynamically functional reorganization in the ipsilateral somatosensory cortex suggesting a remarkable plasticity of the brain function induced by an alteration of sensory input between two sides of the body in adult rats.

Objective To study the effect of stellate ganglion blocking (SGB) during cardiopulmonary bypass (CPB) on inflammatory reaction.Methods Twenty patients undergoing mitral valve replacement were randomly allocated to 2 matched groups,control group and SGB group (n=10).The control group only received conventional anesthesia,while the SGB group was blocked with 1% lidocaine in addition before the operation for SBG.Blood glucose (BG),Cortisol (Col),IL-1?,IL-6 and TNF-? in the venous blood samples were detected in following 5 time points,20 min before anesthesia,20 min after anesthesia,20 min after operation,20 min afer the start of CPB and 20 min after the end of CPB.Results Col level of the control group (353.09?129.34 ng/ml) was significantly higher than that of the SGB group (486.84?152.20 ng/ml) in 20 min after the end of CPB (P