1.THE EFFECTS OF CLONIDINE ON MEMBRANE PROPERTIES OF THE NEURONS OF GUINEA-PIG CELIAC GANGLIA
Ruchun MA ; Ruiling WU ; Yijian DONG
Chinese Pharmacological Bulletin 1986;0(05):-
This work was carried out to investigate the effects of clonidine on some electrophysiological properties of the neurons of guinea-pig celiac ganglia in vitro, using the technique of intracellula.r recording. 54 neurons were examined, among which 18 neurons were found to be sensitive to clonidine. There were 3 reaction types in the sensitive cells, depolarization with decrease of membrane resistance, hyperpolarization with increase of membrane resistance and biphasic reaction ( depolarization followed by hyperpolarization ) . Clonidine depolarization was not blocked by low Ca^/high Mg2+ solution, pro-pranolol and yohimbine. However, it was reversibly blocked by prazo-sin. The experimental results show that clonidine has some! effects on the membrane potential and membrane resistance of the neurons of guinea-pig celiac ganglia,
3.Osteocyte density may be an important influencing factor for the bone biomechanical property
Yulin MA ; Ruchun DAI ; Zhifeng SHENG ; Yuhai ZHANG ; Yan JIN ; Eryuan LIAO
Chinese Journal of Geriatrics 2009;28(6):500-504
Objective To investigate osteocyte density as a potential index of bone biomechanical property. Methods Forty 7-month-old female Sprague-Dawley rats were randomly group (EST) and sham operation group (SHAM). At 15 weeks postoperation, the compression test was performed on L5 vertebral body and micro-computed tomography (μ-CT) was used to estimate the three-dimensional bone mineral density (BMD) and three-dimensional microstructure parameters of L6 vertebral body. After fatigue damage testing, the L6 vertebral body was bulk-stained in 1% basic fuchsin and embedded in methylmethacrylate. Mounted bone slices were used to measure microcrack parameters and osteocyte density. Results At 15 weeks postoperation, osteocyte density (Ot. N/T. area) was significantly decreased in OVX group compared with SHAM group and EST group [(1268. 1 ±191.2)/mm2 vs. (1760. 8 ± 376.6)/mm2 and (1550. 9± 202.2)/mm2, F = 3.513,P<0. 05]. Maximum load (ML) was significantly decreased and the length of microcrack (Cr. Le) was significantly increased in OVX group compared with SHAM group, EST group and GEN group [(84. 4±16.9)N vs. (110.3±25.6),(103. 9±15. 8)and(110.1±4. 9)N; (58. 1±6.8) μm vs. (24.2±8. 1), (36. 5±9. 7)and(28.5±7. 5)μm, F=9. 561,3. 179, all P<0. 05]. Compared with SHAM group and EST group, bone trabecula connection density (Conn. D) was significantly decreased and trabecular separation (Tb. Sp) was significantly increased in OVX group [(47.4±7.4) m-3 vs. (71.8±16.0)and (74.0±12.7)m-3;(315.0±32.7)μm vs. (222. 5±21.7)and (273.3± 50.0)μm, F=7. 635,7. 007, all P<0. 05]. Bone mineral content (BMC) was lower in OVX group than that in SHAM group[(6.5±2. 2)g vs. (7. 9±1.2)g, P<0. 05]. When data in four groups were overall analyzed, Ot. N/T. Ar was positively correlated with ML, Conn. D and BMC (R2 = 0. 7874, 0. 1153, 0. 1309, all P<0. 05), but was negatively correlated with Cr. Le and Tb. Sp (R2 =0. 5738, 0. 3964, both P < 0.05). Conclusions Osteocyte plays a crucial role in maintaining bone biomechanical property and osteocyte density may be considered as a useful indicator for assessing bone biomechanical property.
5.Slow synaptic transmission mediated by 5-HT_(1P) receptor in sympathetic ganalion of guinea pig
Liecheng WANG ; Yan ZHU ; Yanlong HE ; Jinlan HU ; Zhenxin HUANG ; Ruchun MA
Chinese Pharmacological Bulletin 1986;0(05):-
AIM To investigate the effects of several 5-hydroxytryptamine(5-HT) subtype receptor antagonists on late slow excitatory postsynaptic potential(LS-EPSP) of the neurons of guinea pig inferior mesenteric ganglion(IMG). METHODS Intracellular recordings were made from neurons of the isolated guinea pig IMG. RESULTS Cyproheptadine and BRL 24924 suppressed LS-EPSP of 5-HT sensitive neurons reversibly, while mianserin, MDL 72222 and spiperone showed no significant effect. Continuous superfusion of IMG with MCPP suppressed LS-EPSP of 5-HT sensitive neurons by 5-HT 1P receptor desensitizated. CONCLUSION LS-EPSP of 5-HT sensitive neuron is mediated by 5-HT 1P subtype receptor.
6.Effect of Intravesical Instillation Therapy on Cancer-specific Survival Rate of Stage T1 Non-muscle-invasive Bladder Transitional Cell Carcinoma Patients After Transurethral Resection
Cancer Research on Prevention and Treatment 2022;49(12):1269-1275
Objective To investigate the effect of transurethral resection of bladder tumor (TURBT) with or without intravesical instillation therapy on cancer-specific-survival rate (CSS) of T1 stage non-muscle-invasive bladder transitional cell carcinoma (BTCC) patients. Methods The data of patients diagnosed with T1 stage non-muscle-invasive BTCC from 2010 to 2015 were obtained from the SEER database. The different dividing groups were based on TURBT with or without intravesical instillation therapy. A 1:1 PSM method was used to balance the differences in baseline data between each group. Herein, Kaplan-Meier methods were used to draw survival curves, and the difference between OS and CSS were compared by Log rank test. In addition, univariate and multivariate Cox regressionanalyses were used to explore the independent risk factors of CSS. Results The OS and CSS of patients in the TURBT combined with intravesical instillation therapy group were higher than those of the TURBT alone group (
7. Duration time and effectiveness of 0.25%ropivacaine for sciatic nerve block in patients with diabetes
Hongyu DAI ; Kun YANG ; Ruchun HU ; Hongmei ZHOU ; Peimin MA ; Qian HAO
Chinese Journal of Clinical Pharmacology and Therapeutics 2022;27(11):1278-1284
AlM: To compare the duration of 0.25% ropivacaine used for sciatic nerve block between type 2 diabetic patients and non-diabetic patients, and to explore the factors affecting the duration of nerve block. METHODS: Sixty eight patients with unilateral lateral malleolus fracture who were to be treated with open reduction and internal fixation were selected from January 2021 to January 2022, aged 20-80 years old, ASA I-III, including 28 diabetic patients and 40 non-diabetic patients. All patients were given 0.25% ropivacaine 20 mL to the superior popliteal sciatic nerve under the guidance of ultrasound. The onset and duration of sensory block were evaluated by blunt needle stimulation. The onset and duration of motor block were evaluated by dorsiflexion and plantar flexion of the operated foot. The interval between the end of the operation and the patientls first request for analgesia was taken as the duration of nerve block analgesia. RESULTS: Compared with non-diabetic patients, the duration of sciatic nerve sensation, motor block and analgesia in diabetic patients were prolonged (P < 0.05). There was no significant difference in the onset time of sciatic nerve sensation and motor block between the two groups (P > 0.05). Linear regression analysis showed that diabetes mellitus, duration of diabetes mellitus, fasting blood glucose and glycosylated hemoglobin were factors affecting the duration of nerve block, and fasting blood glucose was not related to the duration of analgesia. CONCLUSlON: 0.25% ropivacaine can prolong the duration of sciatic nerve block in diabetic patients. The duration of diabetes, diabetes, fasting blood glucose and glycosylated hemoglobin are positively correlated with the duration of block.