利多卡因在兽医临床上的应用

利多卡因属于中效酰胺类局部麻醉药,兽医临床上多用于局部表面或浸润麻醉,其主要作用还包括镇痛、抗心律失常和促动力学等。利多卡因廉价易得,但目前兽医临床上对于利多卡因其他方面的应用却不如局部麻醉广泛,这不仅关系到药物的充分应用,也关系到动物福利。通过查阅国外文献,对利多卡因在兽医临床上的应用进行综述,以期给临床兽医用药提供参考,更好地为患畜解除病痛,提升动物福利。     

盐酸赛拉嗪和盐酸氯丙嗪复合麻醉在野生动物中的应用

通过杭州动物园兽医多年的临床实践验证,使用盐酸赛拉嗪和盐酸氯丙嗪复合麻醉野生动物效果安全稳定。该麻醉方法临床应用也相当广泛,包含杭州动物园大多数动物。梅花鹿、马鹿和旋角羚3~4mg/kg(盐酸噻拉嗪,下同)体重用量,可以达到深麻状态,诱导期较短,麻醉深入稳定;黇鹿和黑麂10~15mg/kg体重,可以达到深麻状态,诱导期相对较长,需要30min以上,效果稳定;斑马用此麻醉方法效果不佳,但是6~8mg/kg体重用于镇静串笼,过程安全且省力;对食肉动物用量为6~8mg/kg体重,种间差异小,麻醉效果佳。文中将各动物的麻醉应用情况总结统计,旨在为兽医临床麻醉的应用提供参考。     

常见麻醉药在兽医临床上的应用研究

探究在兽医临床过程中应用的麻醉药物药效,有利于提升治疗对象的依从性,对提升治疗效果大有裨益。本文在对常见的非吸入性麻醉药物进行综合阐述的基础上,介绍了吸入性麻醉药物在兽医临床中的运用,以期为相关人士提供借鉴和参考。     

动物毛发中β-受体激动剂残留消除规律及检测技术研究进展

畜禽养殖环节违法添加β-受体激动剂类药物,导致畜产品安全事件多发,我国政府对畜产品中β-受体激动剂监管高度重视。而动物毛发中β-受体激动剂残留消除缓慢,且毛发取样方便、无创伤、易于保存,作为监管β-受体激动剂在畜禽养殖环节违法添加的靶标具有很大优势。综述了毛发的结构特性与生长规律、药物进入毛发机制、动物毛发中β-受体激动剂残留消除规律及检测技术,旨在为毛发作为可能的监管靶标提供科学依据。     

脑室注射脑啡肽和纳洛酮对北京鸭胃酸分泌的影响

本实验观察了第三脑室注射甲硫氨酸脑啡肽和阿片受体阻断剂纳洛酮对北京鸭胃酸分泌的影响,结果表明：（１）将５μｌ脑啡肽（０．０７５ｇ／Ｌ）注入脑室后,北京鸭胃酸分泌明显抑制,且注药后２０ｍｉｎ抑制作用最为显著,（２）预先注射阿片受体阻断剂纳洛酮后,再注射同样剂量的脑啡肽,抑制胃酸分泌的现象消失,结果提示,脑室注射脑啡肽对胃酸分泌有抑制作用,此作用是通过作用于阿片受体而实现的。     

脑室注射啡肽和纳洛酮对北京鸭胃酸分泌的影响

本实验观察了第三脑室注射甲硫氨酸脑啡肽和阿片受体阻断剂纳洛酮对北京鸭胃酸分泌的影响。结果表明：（１）将５μｌ脑啡肽（０．０７５ｇ／Ｌ）注入脑室后，北京鸭胃酸分泌明显抑制，且注药后２０ｍｉｎ抑制作用最为显著。（２）预先注射阿片受体阻断剂纳洛酮后，再注射同样剂量的脑啡肽，抑制胃酸分泌的现象消失。结果提示，脑室注射脑啡肽对胃酸分泌有抑制作用，此作用是通过作用于阿片受体而实现的。     

阿片受体类型和功能及其在猪脑中的个体发育特点

总结阿片受体类型的研究进展,介绍4种主要类型受体的功能。动物脑中阿片受体的数量以及它们与阿片配体亲和力的改变能够对脑功能的阿片控制或内分泌系统的中枢神经控制产生影响。为明确猪脑中阿片受体的变化,阐述了阿片受体在猪脑中的个体发育特点。     

β-受体激动剂在饲养肉用动物体内的代谢与残留研究进展

β-受体激动剂是一类人工合成药物,其主要用于防治支气管哮喘,但对于人体和动物都有很强的副作用。多国学者对生物样本猪、牛、羊、鼠、鸡体内β-受体激动剂的代谢与残留消除做过研究,对其血液、排泄物、内脏、肌肉、眼睛、毛发在动物服药期和停药期进行检测。β-受体激动剂口服或注射均易被机体吸收,主要以原型药物的形式经肾脏排泄,排泄迅速。在动物体内残留量的多少与动物的种属、给药剂量、给药期有关。残留浓度大小顺序为眼睛>肺脏>肝脏>肾脏>血清>脂肪>肌肉>心脏。β-受体激动剂在眼睛和心脏中代谢较慢,其次是肺脏和肾脏,代谢最快的是脾脏。眼睛和毛发中蓄积的克伦特罗浓度和其色素浓度大小成正相关,代谢比较缓慢且含量比较稳定,是检测残留比较理想的靶器官。     

技术遇难题 专家来帮忙

候加法（兽医专家）南京农业大学动物医学院博士导师。长期从事临床兽医外科学教学和科研工作。主要研究方向：小动物疾病学；畜禽骨骼生物学；小动物外科学；小动物临床麻醉与应用。     

《兽医药理学》课程教学改革的研究

《兽医药理学》是动物医学的一门重要专业基础课程，也是基础动物医学与临床兽医学、临床医学之间　的桥梁学科。它运用生理生化、微生物学及免疫学知识认识、理解药物的作用及作用机理，又直接应用于兽医临床各个学科。自２０世纪我国建立兽医学校、兽医系、兽医学院并开设兽医药理学以来，特别是改革开放以来，兽医基础药理、临床药理和药物动力学都有很大的发展，新型兽药不断涌现，畜牧生产和兽医临床用药已由大中家畜的散养个体用药为主，向中小家畜的集约化群体用药为主转变。在兽医药理学课程内容大大增加、教学时数反而压缩（我校总…     

白芷香豆素的镇痛机制初探

目的探讨白芷香豆素（Coumarin of Angelicae dahuricae,CAD）的镇痛作用机制．方法采用热板法,通过工具药观察CAD的镇痛作用与阿片受体和单胺类神经递质的关系;利用硝酸还原酶法检测CAD对甲醛所致伤害性疼痛模型小鼠血清一氧化氮（NitricOxide,NO）的含量．结果纳洛酮（5mg／kg）部分拮抗CAD（60mg／kg）的镇痛作用;利血平（4mg／kg）可以部分拮抗CAD（60mg／kg）的镇痛作用．CAD（30,60,120mg／kg）连续给药4d,使甲醛所致伤害性疼痛模型小鼠血清NO含量明显下降．结论CAD具有明显的镇痛,其镇痛作用与阿片受体和脑内单胺类神经递质有一定的关系．此外,明显减少NO的合成可能是其发挥镇痛作用的重要机制．     

Neuroanatomical correlates of morphine dependence

Naloxone hydrochloride, an opioid antagonist, was applied to several discrete brain regions of morphine-dependent rats to precipitate abstinence. Severe withdrawal signs were elicited after administration in the thalamus but not in neocortical, hippocampal, hypothalamic, or tegmental areas of the brain.     

Both mu and delta opiate receptors exist on the same neuron

Low concentrations of the relatively selective opiate receptor agonists dihydromorphine and normorphine (mu receptor agonists) and D-Ala 2-D-Leu 5-enkephalin (a delta receptor agonist) were applied to single enteric neurons while the frequency of action potential firing was recorded. Most neurons that were inhibited by the mu agonists were also inhibited by the delta agonist, but the two receptors could be distinguished by the higher concentration of naloxone required to antagonize the delta agonist. The results indicate that enteric neurons bear both mu and delta receptors and that cell firing is inhibited if either receptor type is activated.     

Endotoxin-stimulated opioid peptide secretion: two secretory pools and feedback control in vivo

Small doses of endotoxin evoked a dramatic biphasic response of opioid peptide secretion into blood in sheep. The first phase began within minutes and coincided with a brief hypertensive response to endotoxin well before the appearance of fever or hypotension. The ratio of beta-endorphin to beta-lipotropin fell abruptly at the onset of the second phase of release, suggesting early depletion of a pool rich in beta-endorphin and subsequent emergence of a pool rich in unprocessed precursor. The concentration of cerebrospinal fluid opioids increased tenfold during the second phase. Naloxone administration augmented endotoxin-induced opioid secretion in both early and late phases, suggesting a short-loop feedback regulation of stress-induced endorphin secretion.     

Psychotomimesis mediated by kappa opiate receptors

The kappa opioid agonists are analgesics that seem to be free of undesired morphine-like effects. Their dysphoric actions observed with the kappa agonist cyclazocine are thought to be mediated by an action at sigma-phencyclidine receptors. The benzomorphan kappa agonist MR 2033 is inactive at sigma-phencyclidine receptors. In male subjects, the opiate-active (-)-isomer, but not the (+)-isomer, elicited dose-dependent dysphoric and psychotomimetic effects that were antagonized by naloxone. Thus, kappa opiate receptors seem to mediate psychotomimetic effects. In view of the euphorigenic properties of mu agonists, our results imply the existence of opposed opioid systems affecting emotional and perceptual experiences.     

Naloxone antagonism of the thermoregulatory effects of phencyclidine

Phencyclidine elicits hyperthermia at low doses and hypothermia at high doses in rats. Naloxone antagonizes both effects. Phencyclidine's effects on thermo-regulation are probably mediated by an interaction with a mu opiate receptor.     

马Mu阿片受体基因第一外显子的PCRSSCP分析

[目的]采用PCR．SSCP方法对马Mu阿片受体基因第一外显子压域进行分析,以求发现SNP位点。[方法]以纯血马、三河马、乌珠穆沁马、锡尼河马、巴尔虎马和乌审马6个类型马共计297个个体的血样为研究材料,对马Mu阿片受体基因的第一外显子进行PCR扩增和PCR—SSCP分析,并比较不同品种的基因型频率。[结果]通过PCR-SSCP分析确定不同品种马MOR基因第一外显子区域存在多态性,共发现了AA、AB和BB3种基因型,且AA型为优势基因型,等位基因A较B为优势等位基因.除纯血马外,其他各群体中3种基因型均有分布。对AA和BB2种基因型个体PCR产物进行的竞隆测序发现,AA型在第167位发生了A—G的转换。[结论]该研究为丰富马品种的种质特性资料库和分子育种提供理论依据。     

眠乃宁对熊化学保定的试验研究

眠乃宁是利用国产药物合成的一种复方麻醉剂,作用于中枢α—受体和吗啡受体。对13只熊的使用效果表明,眠乃宁对棕熊和黑熊的麻醉保定期比其它麻醉药保定期长。注入眠乃宁后3～5min出现反应,诱导期为5min6s～15min12s。恢复期(完全苏醒)与保定期成正比。该药品可作为兽类化学保定的理想麻醉剂。     

Spinal sympathetic neurons: possible sites of opiate-withdrawal suppression by clonidine

Morphine, methadone, meperidine, fentanyl, and clonidine rapidly depressed transmission through sympathetic preganglionic neurons in cats with the spinal cord transected. Naloxone promptly antagonized this effect of the opiates but not that of clonidine which was reversed by alpha 2-adrenergic receptor antagonists. The independent depression of preganglionic neurons by clonidine may contribute to the ability of this drug to depress the symptoms of opiate withdrawal that are characterized by sympathetic hyperactivity.