薄荷醇对戊巴比妥中枢抑制作用的影响

研究薄荷醇经胃肠道给药对成巴比妥中枢抑制作用的影响，结果发现，薄荷醇对戊巴比妥的中枢抑制作用具有一定的量效关系，含４．５％的薄荷醇溶液可明显使小鼠的入睡时间缩恒，并使急性死亡率增加，而含１．５％和０．５％的薄荷醇溶液对成巴比妥的中枢抑制作用无明显影响。     

Titration of duration discrimination in behavioral pharmacology and toxicology

This study investigated a discrete-trial, titration duration discrimination procedure in behavioral pharmacology. Pentobarbital and d-amphetamine, measured with this procedure, selectively affected discrimination more than response tendencies. Pentobarbital also tended to affect selectively discrimination of longer durations, whereas d-amphetamine did not. Further experiments showed that (1) other algorithms for modulating stimulus duration are useful in behavioral pharmacology and toxicology, (2) threshold estimates are similar with the method of constant stimuli and the method of titration, and (3) this titration procedure permits the separate examination of drug effects upon discrimination and upon response tendencies; the fixed-interval procedure does not. Baseline variability was an important correlate of drug effects in that the endpoints with more variable baselines were also more sensitive to drugs.     

A Pilot Study: Defibrillation Thresholds in Dogs are Similar with Isoflurane, Halothane, and Pentobarbital

The objective of this pilot study was to determine if three common anesthetic drugs have differing effects on the measurement of defibrillation thresholds (DFT) in dogs. The drugs compared were pentobarbital, isoflurane, and halothane. We used six dogs, which were surgically instrumented, in a chronic study design. Each dog had two internal defibrillation patches placed on its heart, which were used to deliver the defibrillation energy. DFT was determined while each dog was anesthetized under each of the listed drugs in a crossover design. This pilot study suggests that differences in DFT due to the anesthetic drugs is not significant in studies with low numbers of animals (halothane 14.5 ± 1.0, isoflurane 14.2 ± 1.0, pentobarbital 12.8 ± 1.0;P = NS; mean ± SE). Tbe variation in DFT between individual animals is much larger than the difference in DFT due to the drugs.     

基底外侧杏仁核注射戊巴比妥钠对睡眠和行为的影响

目的 观察基底外侧杏仁核（ＢＬＡ）内注射戊巴比妥钠对睡眠和行为的影响。方法 多导睡眠描记术和杏仁核微量注射。结果 戊巴比妥钠引起觉醒减少,慢波睡眠和总睡眠时间增多,开野实验中踩格数和修饰行为减少,而强迫游泳实验的不动时间延长。结论 戊巴比妥钠作用于ＢＬＡ可产生明显的促睡眠效应和镇静作用,ＢＬＡ参与了睡眠和行为的调节。     

灯盏细辛和灯盏花素对戊巴比妥钠致小鼠催眠的影响

目的:观察灯盏细辛和灯盏花素对戊巴比妥钠催眠小鼠的影响。方法:将小鼠随机分为灯盏细辛组、灯盏花素组、纳洛酮组及生理盐水组,观察对阈上剂量和催眠剂量的戊巴比妥钠致小鼠睡眠的影响,并考察了对小鼠自发活动和对小鼠的平衡功能影响。结果:灯盏细辛组、灯盏花素组及纳洛酮组与生理盐水组比较,能显著延长阈上剂量戊巴比妥钠致小鼠入睡时间,缩短睡眠持续时间(P＜0．05);缩短催眠剂量戊巴比妥钠所致小鼠翻正反射消失的持续时间(P＜0．05);对小鼠自发活动和小鼠平衡功能无明显影响。结论:灯盏细辛和灯盏花素对戊巴比妥钠催眠小鼠有催醒作用。     

戊巴比妥钠麻醉对分离培养大鼠心肌细胞的影响

目的探讨戊巴比妥钠常用麻醉剂量对分离培养成年大鼠心肌细胞的直接作用。方法分对照组和戊巴比妥钠组（30mg／kg腹腔注射），分离心肌细胞测细胞存活率和单个细胞收缩幅度。结果与对照组相比，戊巴比妥钠组心肌细胞存活率下降（P〈0．01），单个细胞收缩幅度降低（P〈0．05）。结论常用剂量下戊巴比妥钠即可降低心肌细胞存活率，直接抑制心肌细胞收缩幅度。     

氯胺酮麻醉对大鼠局灶性脑缺血模型病理结局的影响

目的:研究氯胺酮麻醉对大鼠局灶性脑缺血模型病理结局的影响. 方法: 雄性SD大鼠30只在戊巴比妥或氯胺酮麻醉下制作永久性大脑中动脉阻塞模型,每组15只. 术后4 h行神经病学评分、24 h测量梗塞体积、3 d进行甲苯胺蓝染色检测半暗带内的神经元. 结果:神经病学评分(1.5±1.0 vs 1.4±0.7)和死亡率(42% vs 33%)在戊巴比妥组和氯胺酮组间无显著性差异(P＞0.05),但氯胺酮组的脑梗塞体积小于戊巴比妥组[(28.1±4.1)% vs (37.8±5.0)%, P＜0.05],且半暗带内的神经元密度高于戊巴比妥组[(836±15)个/mm2 vs (740±24)个/mm2, P＜0.05]. 结论:在制作大鼠局灶性脑缺血模型时,氯胺酮麻醉下产生的脑损伤较轻. 在氯胺酮麻醉下的大鼠局灶性脑缺血模型中评价一些药物或方法的神经保护作用时,应考虑到氯胺酮的神经保护作用.     

CNS tolerance to the hypnotic effect of pentobarbital in rats by injections of pentobarbital suspension.

Functional (CNS) tolerance to the hypnotic effect of barbiturates was determined in vivo by comparing the brain barbiturate level at awakening from a test dose in control rats and rats chronically treated with barbiturate. Approximately two-fold CNS tolerance to barbital was achieved by giving rats increasing concentrations of barbital in their drinking water according to trie schedule of Morgan, Pfeil and Gonzales (1977), but the tolerance was lost after the three days of withdrawal necessary to eliminate the drug from the brain. No significant CNS tolerance to the hypnotic effect of pentobarbital was developed when it was administered in the rats' food or water on various schedules. Administration of pentobarbital by daily injections of the drug in suspension, however, resulted in approximately 1.5-fold CNS tolerance to the hypnotic effect of this barbiturate in 5–10 days. Barbiturates in vitro inhibit K-stimulated ACh release from brain slices; the degree of inhibition by pentobarbital in vitro was not changed after chronic pentobarbital suspension injections in vivo.     

Cardioprotective effects of desflurane: effect of timing and duration of administration in rat myocardium

Background. We compared the cardioprotective effects of 1 minimumalveolar concentration (MAC) desflurane administered before,during or after ischaemia, or throughout the experiment (before,during and after ischaemia) on myocardial infarct size following30 min occlusion of the left anterior descending coronary arteryand 3 h reperfusion in adult rats. Methods. Fifty male Sprague–Dawley rats were anaesthetizedwith pentobarbital, intubated and mechanically ventilated. Bloodgases, pH and body temperature (37.5–38°C) were controlled.Heart rate and arterial pressure were measured continuously.Animals were randomly assigned to the following groups (n=10in each group): pentobarbital only (‘Pento’); 15min desflurane administration followed by 10 min of washoutbefore 30 min ischaemia and 3 h reperfusion (‘Precond’);30 min desflurane administration during ischaemia period (‘Isch’);desflurane administration during the 15 first min of reperfusion(‘Reperf’) and desflurane administration throughoutthe experiment (before, during and after ischaemia; ‘Long’).Volumes at risk and infarct sizes were assessed by Indian inkand with 2,3,5-triphenyltetrazolium chloride staining, respectively. Results. Physiological parameters and volumes at risk were notsignificantly different between groups. In the Pento group,mean myocardial infarct size was 65 (SD 15)% of the volume atrisk; myocardial infarct size was reduced to a significant andcomparable extent in the desflurane-treated groups (Precond42 (14)%; Isch 34 (11)%; Reperf 41 (15)%; Long 33 (10)%; P<0.0002vs Pento group). Conclusions. In rats, desflurane 1 MAC significantly decreasedmyocardial infarct size whatever the period and duration ofadministration. Br J Anaesth 2004; 92: 552–7     

独活香豆素组分对戊巴比妥钠及巴比妥钠催眠作用的影响

目的观察独活香豆素组分(TCA)对戊巴比妥钠及巴比妥钠催眠作用的影响。方法将小鼠随机分为溶媒(5%吐温-80,20mL/kg)、氯霉素(25mg/kg)及TCA(50、100mg/kg)组,等容灌胃给药1h后,再腹腔注射戊巴比妥钠40mg/kg或巴比妥钠200mg/kg,观察催眠潜伏期和催眠时间。结果氯霉素和高、低剂量的TCA使戊巴比妥钠的催眠时间延长249.8%、171.1%和78.7%,均P<0.01;对巴比妥钠的催眠作用无明显影响。结论TCA对小鼠肝微粒体细胞色素P450具有一定的抑制作用。