Hemodynamic Comparison between Bupivacaine and Levobupivacaine Induced Cardiovascular Collapses in Anesthetized Dogs / 대한구급학회지

BACKGROUND: Levobupivacaine is known to be less cardiotoxic than racemic bupivacaine but some authors have reported there were no differences in cardiotoxic profiles between two agents. We will investigate the full course to cardiovascular collapse induced by bupivacaine stereoisomers in anesthetized dogs and would find out the differences if any, and explain the causative factors. METHODS: Twenty dogs were assigned to two groups, racemic bupivacaine group (BUP) and levobupivacaine group (LBUP), equally (n=10, each). Under general anesthesia each drug was infused continuously (0.5 mg/kg/min) until cardiovascuar collapse (CVC, MAP=40 mmHg) occurred. During the experiment, hemodynamic data, CO, SVR, PVR, ECG parameters and drug concen tration were gathered and analyzed. RESULTS: Two groups were not different in terms of dose for CVC, plasma drug concentration and time for CVC. MAP maintained initial values during the early period and declined during the late period without any between-group difference. Otherwise CO decreased continuously and significantly higher in LBUP than in BUP throughout. Calculated SVR showed the same feature as CO in opposite direction and was higher in BUP. Correlation test revealed high correlation between CONC and SVR or PVR and between CO and cSvO2. CONCLUSIONS: In assessment of cardiovascular collapse induced by stereoisomers of bupivacaine, monitoring with only MAP can lead to misinterpretation and invasive monitoring including CO or cSvO2 measurement might be needed.

The effect of ZDY102 on brain M receptor in dementia model rats / 中国药理学通报

Aim To observe the effect of ZDY102, a C25 stereo-isomer of ZMS, the active component of Zhimu, on brain M receptor density of dementia model animals and the correlation with its effect on learning/memory ability. Methods The rats were randomly divided into five groups: control group, model group, model given orally for 2 months with 3.6 mg?kg -1?d -1 of ZDY102 treatment, model treated with 9.0 mg?kg -1?d -1 of ZDY102, and model treated with 18.0 mg?kg -1?d -1 of ZDY102. Dementia model was produced by single unilateral injection of 4 ?l of normal saline containing 4 ?g of ?-amyloid (25～35) and 1 ?g of ibotenic acid into right basal ganglion region with the aid of a stereotaxic equipment. The brain muscarinic receptor density was analyzed with single-site binding assay using 3H-quinuclidinyl benzilae(QNB). The learning/memory ability was measured by Y-maze performance. Results Two months after model production, the learning and memory ability as well as the density of muscarinic receptor in brain were significantly decreased in model rats compared with those in control rats. Parallel models treated with daily oral administration of ZDY102 for two months improved in learning and memory ability and their muscarinic receptor density was significantly increased when compared with model rats. The correlation coefficient between total M receptor densities and the learning/memory ability was significant when examined with linear regression. Conclusion ZDY102 can significantly improve the learning and memory ability and increase the brain muscarinic receptor density of the model. Since brain muscarinic receptors are closely correlated to learning and memory, up-regulation of M receptor density might play a very important role in the therapeutic effect of ZDY102.