Objective To investigate the effects of droperidol on the Na+ currents in rat dorsal root ganglion neurons.Methods The rat dorsal root ganglion neurons were enzymatically dissociated. Whole-cell patch-clamp technique was applied to record Na+ current. Results 3-300?mol?L-1 Droperidol inhibited the sodium currents by 14.12%-78.46% (P0.05, n =7).Conclusions Droperidol inhibits Na+ currents in rat dorsal root ganglion neurons in a concentration- and voltage-dependent manner. The results suggest that the concentration of epidural droperidol clinically applied during epidural patient control analgesia may enhance the analgesic effects.

Objective: To explore the effects of desflurane on systemic and hepatic hemodynamics and oxygen delivery to the liver. Method: 11 healthy mongrel dogs were anesthetized with 0.5 and 1.0 MAC desflurane respectively. The changes of systemic, pulmonary and hepatic hemodynamics,systemic oxgen delivery and consumption,oxygen delivery to the liver were measured continuously. Blood flow of hepatic artery and portal vein was monitored with electromagnetic flowmeter. Result: During inhalation of 0.5 MAC desflurane,HR.MAP.SVR,portal vein and total hepatic oxygen delivery decreased significantly(P

Objective The effect of lidocaine and bupivacaine on the Na+ current of dorsal horn neurons was observed to further evaluate the mechanism of local anesthetics . Methods The dorsal horn neurons of the SD neonates(0-7 d) were isolated acutely. Under the condition of holding voltage -80mV , and testing voltage -30mV with duration of 20 ms , the whole-cell patch-clamp technique was applied to recording the changes of voltage-gated Na+ currents following the administration of lidocaine or bupivacaine at 50-1000?mol/L.Results The voltage-gated Na+ currents ranged from 0.5-8nA peak amplitude , was inhibited by lidocaine and bupivacaine at clinical concentrations, the inhibitory degree was parallelly correlated with the concentration of local anesthetics(r=0.949 and 0.847 ,P

Objective To study the effects of desflurane on Ca 2+-ATPase activity isolated rat cardiac myocyte plasma membrane ,for the mechanisms of its inhibitory myocardial function.Methods The effects of different concentration desflurane(0%-11%) on Ca 2+-ATPase activity were studied at different calcium concentration(04-20?mol/L) and at 25℃ or 37℃Results Ca 2+-ATPase activity wan depressed by desflurane,the greater inhibitory effect,the higher desflurane concentration,and more severely at low calcium concentration or at 37℃ than at high calcium concentration or at 25℃Conclusions At clinical concentration desflurane produces tha inhibitory effect on rat cardiac myocyte plasma membrane Ca 2+-ATPase activity dose-dependently,which may in part explain its depression on myocardial function.

AIM To elucidate the direct effects of propofol and thiopental on cardiac contraction by measuring intracellular Ca 2+ concentration change in cultured rat ventricular myocytes. METHOD Ventricular myocytes of neonatal rats were obtained by enzymatic digestion with typsin and were cultured for 4～5 days, then were loaded with Fluo 3AM, a new Ca 2+ indicator. The effects of propofol (50, 250 ?mol?L -1 ) or thiopental (100, 500 ?mol?L -1 ) on changes of intracellular Ca 2+ fluorescent intensity induced by KCl, isoprenaline or caffeine were investigated. RESULTS Both intravenous anesthetics caused dose dependent inhibit Ca 2+ transsarcolemmal influx induced by KCl and isoprenaline, peak Ca 2+ fluorescent intensity decreased. The inhibitory effect of thiopental was more than propofol at equiopotency. Neither anesthetics altered the amount of Ca 2+ release from intracellular stores in response to caffeine. CONCLUSION The negative inotropic effects of propofol and thiopental, at least in part, may be mediated by a decrease Ca 2+ transsarcolemmal influx though voltage gated and receptor gated calcium channel, but it is not relate to sarcoplasmic reticulum Ca 2+ release.

AIM: To study the interactions of propofol and midazolam on the whole cell sodium channel currents in rat sympathetic ganglion neurons. METHODS: Whole cell patch clamp recordings were made from enzymatically isolated rat (7- 10 d ) superior cervical sympathetic ganglion neurons. Isobolographic analysis was applied to evaluate the potency of combinations of propofol and midazolam on Na + channel currents. RESULTS: Under V h= 80 mV and V t= 0 mV . Propofol and midazolam dose dependently blocked Na + currents with a mean drug concentration required to produce 50% current inhibition (IC 50 ): 33.12 ?mol?L -1 and 18.35 ?mol?L -1 ; clinically relevant concentrations of propofol and midazolam reduced Na + peak currents by 27.66 % (P

AIM: To explore the influence of different concentration midazolam on the macroscopic voltage gated potassium currents and to discuss the relationship between potassium currents and inhibitory effect of clinical relevant concentration midazolam on sympathetic nervous system. METHODS: Superior sympathetic ganglion neurons were dissociated enzymatically from 7 to10 day old rat. Experiments were performed about 5 h after plating at room temperature (20- 24 ℃ ). Appropriate solution was chosen to separate the K + current from the other transmembrane currents. 1 ?mol?L -1 TTX was applied to the extracelluar solution to block the Na + current. Midazolam was also resolved in extracelluar solution to get various concentration ( 0.1 , 0.3 ,3,10,50,100 ?mol?L -1 ). Currents were recorded with the patch clamp technique in whole cell configuration using glass electrodes with a tip resistance of 2- 4 M . Potassium currents were evoked by test pulse from -100 mV to +30 mV with holding potential -80mV. Data were analyzed using Clampfit 6.0 and Oringih 5.0 software. Whole cell current records were corrected for leakage and capacitance by using the P/5 protocol. RESULTS: Midazolam dose dependently inhibited the whole cell potassium currents. Clinical relevant concentration midazolam ( 0.3 ?mol?L -1 ) only reduced the peak currents by 3.89 %(P= 0.88 ). The concentration required to produce 50% current inhibition(IC 50 ) was 76.065 ?mol?L -1 . CONCLUSION: Midazolam inhibits the whole cell potassium current significantly and dose dependently, but clinical relevant concentration midazolam has minor effect on the potassium currents, indicating that the inhibitory effect of midazolam on potassium current is not related to the suppression of activity of sympathetic system.

Objective To summarize the clinical experie nce in the diagnosis and treatment of cystolithiasis complicated by squamous cel l carcinoma (SCC) of the bladder. Methods Retrospective analysis was performed in 28 patients (19 men and 9 women) with cystolithiasis c omplicated by SCC of the bladder.Their age ranged from 26 to 68 years with a mea n of 33 years.The disease course of cystolithiasis ranged from 2 to 18 years wit h a mean of 4.5 years. Among the 24 cases who underwent urine cytology,atypical cells were found in 19 cases.KUB showed solitary stone of the bladder in 5 case and multiple stones in 23.Space-occupying lesions were noted in 11 cases on IVU ,in 17 cases on B-ultrasonography and CT scan.Cystoscopy was performed in 28 ca ses, and tumors were found in 21 cases.The size of the tumors ranged from 1.2 cm ?1.5 cm to 2.2 cm?5.0 cm. Partial cystectomy was performed in 21 cases, includ ing ureterocysto-transplantation in 6 cases.Radical cystectomy was performed in 7 cases. Results Pathology revealed SCC of the bladder in all 28 cases,including G_1 in 11 cases,G_2 in 12 cases,G_3 in 5 cases;T_1 in 11 cases,T_2 in 12 cases,T_3 in 5 cases. Twenty-two patients were followe d up for 1 to 8 years with a mean of 3 years. The 1- and 5-year survival rates were 63.6% (14/22) and 16.7% (3/18),respectively. Conclusions Cystolithiasis is the main cause of SCC of the bladder. Early diagnosis a nd surgical treatment is very important for such patients.

Objective:To determine the microvessel density (MVD) in laryngeal carcinoma and its clinical significance.Method:Thirty-eight tumor specimens were selected from laryngeal cancer patients from January,1994 to March,1996.Histological sections of the tumors were stained immunohistochemically for factor Ⅷ.Using light microscopy,we counted microvessels per 400×field in the most active areas of tumor angiogenesis.Result:①The tumor blood vessels,composed of only one layer of endothelium were mainly distrbuted heterogenously in the interstitial tissue of laryngeal carcinoma with irregular lumen,poorly developed structure.②The MVD in the cancer tissues were statistically higher than that in peritumoral tissues (P＜0.01).③The MVD in the cancer tissues in group of patients with metastasis to cervical lymphonodes were statistically higher than in group without metastasis (P＜0.01),the MVD in the cancer tissues in group of advanced cases (Ⅲ,Ⅳ stages) were statistically higher than that in group of early cases (Ⅰ,Ⅱ stages,P＜0.01).④There was no statistically difference in MVD in the cancer tissue between supraglottic and glottic laryngeal carcinoma patients (P＞0.05).⑤There was no statistically difference in MVD in the cancer tissue among the G1,G2 and G3 group (P＞0.05).Conclusion:The laryngeal cancer blood vessels have some characteristics that don′t appear in normal vessels.It is suggested that tumor angiogenesis can promote tumor growth and metastasis and MVD may be a new prognostic indicator of laryngeal carcinoma.

Objective:To introduce the experience of repairing the defect of cervical trachea wall by using the sternocleidomastoid myoperiosteal flap after the anterior or posterior wall of cervical trachea was invaded by cervical neoplasm. Method:Between 1989 to 1998 the sternocleidomastoid myoperiosteal flap was applied in 12 patients with different diseases, among which 3 cases were thyroid carcinoma, 5 cases were laryngeal carcinoma, 4 cases were cervical esophageal carcinoma. Result:The operation was successful. 12 patients were decannuated and had normal exercise tolerance. The time from reconstruction to decannulation was ranging from 20 days to 6 months. Conclusion: The sternocleidomastoid myoperiosteal flap is an ideal transplant for cervical tracheal reconstruction.