自噬与肺部疾病研究进展

自噬(autophagy)是广泛存在于真核细胞中的基本生命现象,是细胞适应环境变化、防御病原微生物侵袭、维持内环境稳定的重要机制．多种肺部疾病中存在自噬活性的变化,自噬与肺部疾病的发生、发展密切相关．自噬在慢性阻塞性肺病、肺气肿、肺癌、肺结核等许多肺部疾病中发生,且发挥重要作用．现从自噬与多种肺部疾病的关系角度进行综述,有助于了解自噬在肺部疾病中发挥的作用,以便进一步研究自噬的调节,为肺部疾病的治疗提供新思路．     

PHB2抑制低氧性肺动脉高压小鼠右心室重塑的作用

摘要 目的：探讨抗增殖蛋白2（PHB2）在低氧性肺动脉高压（HPH）诱导的右心室重塑中的作用及可能机制。方法：将普通8周龄的C57BL/6小鼠随机分为：对照组（Control）、HPH组、HPH+空病毒（HPH+vector）组、HPH+过表达PHB2（HPH+PHB2）组。HPH组、HPH+空病毒组、HPH+过表达PHB2组置于低压低氧人工舱内维持4 w,对照组置于常压常氧环境中维持4 w。实验开始3 w前,尾静脉注射平滑肌特异性PHB2过表达的AAV9腺相关病毒及其对照病毒。评估小鼠右室血流动力学、右室重塑指标、炎症、氧化应激、血管活性物质水平以及肺组织PHB2和p-Stat3蛋白表达。结果：与对照组相比,HPH组和HPH+空病毒组RVSP、RVAW、RVHI显著增加（P<0.05）,而RVID显著降低（P<0.05）,右室CVF显著增加（P<0.05）,血浆ET-1和BNP显著增加（P<0.05）,血浆NO、总NOS和iNOS显著降低（P<0.05）,右心IL-1β、IL-6及TNF-α显著增加（P<0.05）,SOD和GSH-Px显著降低（P<0.05）,肺组织PHB2表达降低（P<0.05）,p-STAT3表达增加（P<0.05）。与HPH组和HPH+空病毒组相比,HPH+过表达PHB2组RVSP、RVAW、RVHI显著降低（P<0.05）,而RVID显著增加（P<0.05）,右室CVF显著降低（P<0.05）,血浆ET-1和BNP显著降低（P<0.05）,血浆NO、总NOS和iNOS显著增加（P<0.05）,右心IL-1β、IL-6及TNF-α显著降低（P<0.05）,SOD和GSH-Px显著增加（P<0.05）,肺组织PHB2表达增加（P<0.05）,p-STAT3表达降低（P<0.05）。结论：PHB2可减轻HPH诱发的右心室重塑,其机制可能与PHB2抑制STAT3的磷酸化水平有关。     

COPD大鼠肺组织中小窝蛋白-1 的表达及其与气道重塑的关系

目的:探讨小窝蛋白-1(Caveolin-1)在COPD大鼠肺组织中的表达及其与气道重塑的关系。方法:采用10周龄Wister大鼠20只,随机分为对照组与实验组,每组10只,对照组常规饲养,实验组采用烟熏法+内毒素法建立COPD模型。第91天处死全部大鼠,测定肺功能后取肺组织,采用免疫组织化学法检测Caveolin-1的表达;酶联免疫吸附试验(ELISA)检测各组大鼠肺组织匀浆中白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)、转化生长因子-β1(TGF-β1)的含量;分析Caveolin-1的表达与IL-8、TNF-α、TGF-β表达的相关性。结果:与对照组比较,实验组大鼠的肺顺应性明显下降,肺弹性阻力及气道阻力显著升高,肺组织TNF-α、IL-8、TGF-β1的含量明显升高,Caveolin-1的表达明显降低,差异均有统计学意义(P0.05)。大鼠肺组织中Caveolin-1的表达与IL-8、TNF-α、TGF-β1含量呈显著负相关(P0.05)。结论:Caveolin-1在COPD大鼠肺组织中的表达明显降低,可能通过促进炎性细胞因子的释放与气道重塑参与COPD的发生和发展。     

The Role of Proprotein Convertases in Upper Airway Remodeling

Chronic rhinosinusitis (CRS) is a multifactorial, heterogeneous disease characterized by persistent inflammation of the sinonasal mucosa and tissue remodeling, which can include basal/progenitor cell hyperplasia, goblet cell hyperplasia, squamous cell metaplasia, loss or dysfunction of ciliated cells, and increased matrix deposition. Repeated injuries can stimulate airway epithelial cells to produce inflammatory mediators that activate epithelial cells, immune cells, or the epithelial–mesenchymal trophic unit. This persistent inflammation can consequently induce aberrant tissue remodeling. However, the molecular mechanisms driving disease within the different molecular CRS subtypes remain inadequately characterized. Numerous secreted and cell surface proteins relevant to airway inflammation and remodeling are initially synthesized as inactive precursor proteins, including growth/differentiation factors and their associated receptors, enzymes, adhesion molecules, neuropeptides, and peptide hormones. Therefore, these precursor proteins require post-translational cleavage by proprotein convertases (PCs) to become fully functional. In this review, we summarize the roles of PCs in CRS-associated tissue remodeling and discuss the therapeutic potential of targeting PCs for CRS treatment.     

肺心通对慢性肺源性心脏病模型大鼠肺动脉高压、血流动力学及肺血管重构的影响

摘要 目的：研究肺心通对慢性肺源性心脏病（CPHD）大鼠的治疗效果,并探讨其治疗对慢性肺源性心脏病大鼠肺动脉高压、血流动力学以及肺血管重构的影响。方法：30只Wistar大鼠被随机均分为正常对照组（Normal control）、模型组（Model）和肺心通组（Feixintong）。模型组和肺心通组大鼠腹腔注射野百合碱建立CPHD模型,肺心通组CPHD大鼠通过灌胃给药肺心通进行治疗3周。治疗3周后,测量三组大鼠0.3秒呼出量（FEV0.3）、呼出肺功能量（FVC）、肺动脉压、左室射血分数（Left ventricular ejection fraction,LVEF）、左心室舒张末期内径（Left ventricular end diastolic diameter ,LVEDD）、室间隔厚度 （Ventricular septal thickness,IVST）和左室后壁厚度（Left ventricular posterior wall thickness,LVPWT）、肺动脉收缩压（pulmonary artery systolic pressure,PASP）、血氧分压（Partial pressure of blood oxygen,PO₂）、肺动脉平均压（mean pulmonary artery pressure,mPAP）以及舒张压（pulmonary artery diastolic pressure,PADP）以及肺血管重构相关指标。结果：与模型组大鼠相比,肺心通组大鼠活动量、饮食饮水量以及体重均显著增高,呼吸和舌色等症状均改善。肺心通治疗3周后,CPHD大鼠肺功能指标FEV0.3、FVC和FEV0.3/FVC均显著升高（P<0.05）,心脏功能结构指标LVEF、LVEDD、IVST和LVPWT均显著升高（P<0.05）,血流动力学指标PASP、PADP和mPAP均显著降低（P<0.05）,以及肺血管重构指标MA、WT和WA均显著降低（P<0.05）,而肺血管重构指标NMA却显著升高（P<0.05）。结论：肺心通对慢性肺源性心脏大鼠具有较好的治疗效果,可显著降低慢性肺源性心脏大鼠肺动脉高压,改善其血流动力学变化并有助于重构肺血管。     

Analysis of Pulmonary Dendritic Cell Maturation and Migration during Allergic Airway Inflammation

Dendritic cells (DCs) are the key players involved in initiation of adaptive immune response by activating antigen-specific T cells. DCs are present in peripheral tissues in steady state; however in response to antigen stimulation, DCs take up the antigen and rapidly migrate to the draining lymph nodes where they initiate T cell response against the antigen^1,2. Additionally, DCs also play a key role in initiating autoimmune as well as allergic immune response³.DCs play an essential role in both initiation of immune response and induction of tolerance in the setting of lung environment⁴. Lung environment is largely tolerogenic, owing to the exposure to vast array of environmental antigens⁵. However, in some individuals there is a break in tolerance, which leads to induction of allergy and asthma. In this study, we describe a strategy, which can be used to monitor airway DC maturation and migration in response to the antigen used for sensitization. The measurement of airway DC maturation and migration allows for assessment of the kinetics of immune response during airway allergic inflammation and also assists in understanding the magnitude of the subsequent immune response along with the underlying mechanisms.Our strategy is based on the use of ovalbumin as a sensitizing agent. Ovalbumin-induced allergic asthma is a widely used model to reproduce the airway eosinophilia, pulmonary inflammation and elevated IgE levels found during asthma^6,7. After sensitization, mice are challenged by intranasal delivery of FITC labeled ovalbumin, which allows for specific labeling of airway DCs which uptake ovalbumin. Next, using several DC specific markers, we can assess the maturation of these DCs and can also assess their migration to the draining lymph nodes by employing flow cytometry.     

咳嗽变异性哮喘（CVA）与小气道功能相关性分析

目的：探讨咳嗽变异性哮喘（CVA）患者小气道功能检查对其诊断,治疗的意义。方法：对254例以慢性咳嗽为主的患者行肺功能检查并行支气管激发试验,回顾性分析小气道病变及气道高反应性检查结果与咳嗽变异性哮喘（CVA）的相关性。结果：有小气道功能障碍者接受吸入乙酰甲胆碱激发试验,气道反应性明显增高。有小气道功能障碍确诊咳嗽变异性哮喘（CVA）组起始阻力、反应阈值及阻力上升度与非哮喘组相比差异有统计学意义（P〈0.01）。结论：检查小气道功能障碍有助于哮喘的诊断,治疗及预后随访。     

咳嗽变异性哮喘（CVA）与小气道功能相关性分析

目的:探讨咳嗽变异性哮喘(CVA)患者小气道功能检查对其诊断,治疗的意义。方法:对254例以慢性咳嗽为主的患者行肺功能检查并行支气管激发试验,回顾性分析小气道病变及气道高反应性检查结果与咳嗽变异性哮喘(CVA)的相关性。结果:有小气道功能障碍者接受吸入乙酰甲胆碱激发试验,气道反应性明显增高。有小气道功能障碍确诊咳嗽变异性哮喘(CVA)组起始阻力、反应阈值及阻力上升度与非哮喘组相比差异有统计学意义(P<0.01)。结论:检查小气道功能障碍有助于哮喘的诊断,治疗及预后随访。     

Emphysema distribution and annual changes in pulmonary function in male patients with chronic obstructive pulmonary disease

Background

The progression of chronic obstructive pulmonary disease (COPD) considerably varies among patients. Those with emphysema identified by quantitative computed tomography (CT) are associated with the rapid progression assessed by forced expiratory volume in one second (FEV₁). However, whether the rate of the decline in lung function is independently affected by the regional distribution or the severity of emphysema in the whole lung is unclear.

Methods

We followed up 131 male patients with COPD for a median of 3.7 years. We measured wall area percent (WA%) in right apical segmental bronchus, total lung volume, percent low attenuation volume (LAV%), and the standard deviation (SD) of LAV% values from CT images of 10 isovolumetric partitions (SD-LAV) as an index of cranial-caudal emphysema heterogeneity. Annual changes in FEV₁ were then determined using a random coefficient model and relative contribution of baseline clinical parameters, pulmonary function, and CT indexes including LAV%, SD-LAV, and WA% to annual changes in FEV₁ were examined.

Results

The mean (SD) annual change in FEV₁ was −44.4 (10.8) mL. Multivariate random coefficient model showed that higher baseline FEV₁, higher LAV%, current smoking, and lower SD-LAV independently contributed to an excessive decline in FEV₁, whereas ratio of residual volume to total lung capacity, ratio of diffusing capacity to alveolar ventilation, and WA% did not, after adjusting for age, height, weight, and ratio of CT-measured total lung volume to physiologically-measured total lung capacity.

Conclusions

A more homogeneous distribution of emphysema contributed to an accelerated decline in FEV₁ independently of baseline pulmonary function, whole-lung emphysema severity, and smoking status. In addition to whole-lung analysis of emphysema, CT assessment of the cranial-caudal distribution of emphysema might be useful for predicting rapid, progressive disease and for developing a targeted strategy with which to prevent disease progression.     

异丙托溴铵与布地奈德对COPD合并Ⅱ型呼吸衰竭患者MDA,SOD,GSH-Px水平及肺功能的影响

目的:探讨异丙托溴铵联合布地奈德对慢性阻塞性肺疾病合并Ⅱ型呼吸衰竭患者MDA、SOD、GSH-Px水平及肺功能的影响。方法:选取我院收治的慢性阻塞性肺疾病合并Ⅱ型呼吸衰竭患者92例,分为对照组和实验组,每组各46例。对照组采用常规治疗,实验组在对照组基础上加用异丙托溴铵溶液联合布地奈德雾化吸入治疗。观察并比较两组患者治疗前后MDA、SOD及GSH-Px水平的变化情况以及肺功能和血气指标的改善情况。结果:与治疗前比较,两组患者治疗后SOD、GSH-Px、FEV1、VC、Pa O2明显升高,而MDA、RV、TLC、Pa CO2明显降低(P0.05);与对照组比较,实验组治疗后SOD、GSH-Px、FEV1、VC、Pa O2明显升高,而MDA、RV、TLC、Pa CO2明显降低(P0.05)。结论:异丙托溴铵联合布地奈德能够改善慢性阻塞性肺疾病合并Ⅱ型呼吸衰竭患者的肺功能参数、血气指标和MDA、SOD、GSH-Px水平,增强机体抗氧化功能,提高临床疗效。     

Automated Measurement of Microcirculatory Blood Flow Velocity in Pulmonary Metastases of Rats

Because the lung is a major target organ of metastatic disease, animal models to study the physiology of pulmonary metastases are of great importance. However, very few methods exist to date to investigate lung metastases in a dynamic fashion at the microcirculatory level, due to the difficulty to access the lung with a microscope. Here, an intravital microscopy method is presented to functionally image and quantify the microcirculation of superficial pulmonary metastases in rats, using a closed-chest pulmonary window and automated analysis of blood flow velocity and direction. The utility of this method is demonstrated to measure increases in blood flow velocity in response to pharmacological intervention, and to image the well-known tortuous vasculature of solid tumors. This is the first demonstration of intravital microscopy on pulmonary metastases in a closed-chest model. Because of its minimized invasiveness, as well as due to its relative ease and practicality, this technology has the potential to experience widespread use in laboratories that specialize on pulmonary tumor research.     

慢阻肺患者运动负荷气道反应性与T细胞亚群的关系

摘要 目的：探讨与分析慢性阻塞性肺疾病（COPD）患者运动负荷气道反应性与T细胞亚群的关系。方法：2020年1月到2022年4月选择在本院诊治的慢阻肺患者88例作为慢阻肺组,同期选择在本院进行健康体检者88例作为健康组,检测两组T细胞亚群含量,判定两组的运动负荷气道反应性情况并进行相关性分析。结果：慢阻肺组的CD8⁺T淋巴细胞比例明显高于健康组,CD3⁺T淋巴细胞、CD4⁺T淋巴细胞比例明显低于健康组（P<0.05）。慢阻肺组的运动负荷气道反应性发生率为20.9 %,明显高于健康组的1.2 %（P<0.05）。在慢阻肺中,Spearsman分析显示运动负荷气道反应性发生率与CD3+T淋巴细胞、CD4⁺T淋巴细胞、CD8⁺T淋巴细胞比例存在相关性（P<0.05）。logistic回归分析显示CD3⁺T淋巴细胞、CD4⁺T淋巴细胞、CD8⁺T淋巴细胞比例都为影响运动负荷气道反应性发生的重要危险因素（P<0.05）。结论：慢阻肺患者多伴随有T细胞亚群异常,也多伴随有运动负荷气道反应性,运动负荷气道反应性与T细胞亚群存在相关性,也表明T细胞亚群紊乱是导致运动负荷气道反应性发生的重要因素。     

盐酸氨溴索对烟所致慢性阻塞性肺疾病大鼠肺组织细胞凋亡和血管重塑的作用机制研究

目的:盐酸氨溴索对烟所致慢性阻塞性肺疾病(chronic obstructive pulmonary disease, COPD)大鼠肺组织细胞凋亡和血管重塑的作用机制研究。方法:将SD大鼠随机分为4组,每组20只,依次为正常组、模型组、实验组、对照组。模型组、实验组、对照组大鼠采延安香烟烟熏64天构建慢性阻塞性肺大鼠模型,正常组大鼠室温下正常饲养。烟熏结束后,实验组、对照组大鼠每日分别皮下注射5ml盐酸氨溴索(20 mg/kg)和5 m L的盐酸班布特罗(20 mg/kg),正常组、模型组分别腹腔注射等剂量的生理盐水。在药物干预28天后,苏木精-伊红染色(hematoxylin-eosinstaining,HE)、弹力纤维(elastic van gieson,EVG)染色、TUNNEL染色、免疫组化染色、Western blot检测各组大鼠肺组织病理、血管重塑、肺组织的细胞凋亡、α-平滑肌肌动蛋白(α-smoothmus-cleactin,α-SMA)和血管内皮生长因子(Vascular endothelial growth factor,VEGF)的表达、以及Caspase-3、Bax和Bcl-2的表达水平。结果:与正常组相比,模型组肺组织损伤明显,肺小动脉中膜厚度明显增加,血管肌化程度、细胞的凋亡率、α-SMA和VEGF、Caspase-3、Bax的表达明显升高,Bcl-2的表达明显降低,差异均具有统计学意义(P0.05);与模型组相比,实验组和对照组大鼠肺组织损伤明显改善,肺小动脉中膜厚度明显减小,血管肌化程度、细胞的凋亡率、α-SMA和VEGF、Caspase-3、Bax的表达明显降低,Bcl-2的表达明显升高,差异均具有统计学意义(P0.05)。结论:盐酸氨溴索能抑制肺组织的细胞凋亡以及改善其血管重塑,保护COPD大鼠的肺组织。     

Measurement of the Pressure-volume Curve in Mouse Lungs

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential phenotypic changes are best assessed by measurement of the changes in lung elasticity. To best understand specific mechanisms underlying such pathologies in mice, it is essential to make functional measurements that can reflect the developing pathology. Although there are many ways to measure elasticity, the classical method is that of the total lung pressure-volume (PV) curve done over the whole range of lung volumes. This measurement has been made on adult lungs from nearly all mammalian species dating back almost 100 years, and such PV curves also played a major role in the discovery and understanding of the function of pulmonary surfactant in fetal lung development. Unfortunately, such total PV curves have not been widely reported in the mouse, despite the fact that they can provide useful information on the macroscopic effects of structural changes in the lung. Although partial PV curves measuring just the changes in lung volume are sometimes reported, without a measure of absolute volume, the nonlinear nature of the total PV curve makes these partial ones very difficult to interpret. In the present study, we describe a standardized way to measure the total PV curve. We have then tested the ability of these curves to detect changes in mouse lung structure in two common lung pathologies, emphysema and fibrosis. Results showed significant changes in several variables consistent with expected structural changes with these pathologies. This measurement of the lung PV curve in mice thus provides a straightforward means to monitor the progression of the pathophysiologic changes over time and the potential effect of therapeutic procedures.     

An Improved Method for Rapid Intubation of the Trachea in Mice

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity is a commonly used model to study both acute lung injury and fibrosis, and multiple methods have been developed for administering bleomycin (and other toxic agents) into the lungs. However, many of these approaches, such as transtracheal instillation, have inherent drawbacks, including the need for strong anesthetics and survival surgery. This paper reports a quick, reproducible method of intratracheal intubation that involves mild inhaled anesthesia, visualization of the trachea, and the use of a surrogate spirometer to confirm exposure. As a proof of concept, 8-12 week old C57BL/6 mice were administered either 2.0 U/kg of bleomycin or an equivalent volume of PBS, and both damage and fibrotic endpoints were measured post-exposure. This procedure allows researchers to treat a large cohort of mice in a relatively short period with little expense and minimal post-procedure care.     

Minimal Invasive Surgical Procedure of Inducing Myocardial Infarction in Mice

Myocardial infarction still remains the main cause of death in western countries, despite considerable progress in the stent development area in the last decades. For clarification of the underlying mechanisms and the development of new therapeutic strategies, the availability of valid animal models are mandatory. Since we need new insights into pathomechanisms of cardiovascular diseases under in vivo conditions to combat myocardial infarction, the validity of the animal model is a crucial aspect. However, protection of animals are highly relevant in this context. Therefore, we establish a minimally invasive and simple model of myocardial infarction in mice, which assures a high reproducibility and survival rate of animals. Thus, this models fulfils the requirements of the 3R principle (Replacement, Refinement and Reduction) for animal experiments and assure the scientific information needed for further developing of therapeutical strategies for cardiovascular diseases.     

A High-throughput Method for Measurement of Glomerular Filtration Rate in Conscious Mice

The measurement of glomerular filtration rate (GFR) is the gold standard in kidney function assessment. Currently, investigators determine GFR by measuring the level of the endogenous biomarker creatinine or exogenously applied radioactive labeled inulin (³H or ¹⁴C). Creatinine has the substantial drawback that proximal tubular secretion accounts for ~50% of total renal creatinine excretion and therefore creatinine is not a reliable GFR marker. Depending on the experiment performed, inulin clearance can be determined by an intravenous single bolus injection or continuous infusion (intravenous or osmotic minipump). Both approaches require the collection of plasma or plasma and urine, respectively. Other drawbacks of radioactive labeled inulin include usage of isotopes, time consuming surgical preparation of the animals, and the requirement of a terminal experiment. Here we describe a method which uses a single bolus injection of fluorescein isothiocyanate-(FITC) labeled inulin and the measurement of its fluorescence in 1-2 μl of diluted plasma. By applying a two-compartment model, with 8 blood collections per mouse, it is possible to measure GFR in up to 24 mice per day using a special work-flow protocol. This method only requires brief isoflurane anesthesia with all the blood samples being collected in a non-restrained and awake mouse. Another advantage is that it is possible to follow mice over a period of several months and treatments (i.e. doing paired experiments with dietary changes or drug applications). We hope that this technique of measuring GFR is useful to other investigators studying mouse kidney function and will replace less accurate methods of estimating kidney function, such as plasma creatinine and blood urea nitrogen.     

Right Ventricular Systolic Pressure Measurements in Combination with Harvest of Lung and Immune Tissue Samples in Mice

The function of the right heart is to pump blood through the lungs, thus linking right heart physiology and pulmonary vascular physiology. Inflammation is a common modifier of heart and lung function, by elaborating cellular infiltration, production of cytokines and growth factors, and by initiating remodeling processes ¹.Compared to the left ventricle, the right ventricle is a low-pressure pump that operates in a relatively narrow zone of pressure changes. Increased pulmonary artery pressures are associated with increased pressure in the lung vascular bed and pulmonary hypertension ². Pulmonary hypertension is often associated with inflammatory lung diseases, for example chronic obstructive pulmonary disease, or autoimmune diseases ³. Because pulmonary hypertension confers a bad prognosis for quality of life and life expectancy, much research is directed towards understanding the mechanisms that might be targets for pharmaceutical intervention ⁴. The main challenge for the development of effective management tools for pulmonary hypertension remains the complexity of the simultaneous understanding of molecular and cellular changes in the right heart, the lungs and the immune system.Here, we present a procedural workflow for the rapid and precise measurement of pressure changes in the right heart of mice and the simultaneous harvest of samples from heart, lungs and immune tissues. The method is based on the direct catheterization of the right ventricle via the jugular vein in close-chested mice, first developed in the late 1990s as surrogate measure of pressures in the pulmonary artery^5-13. The organized team-approach facilitates a very rapid right heart catheterization technique. This makes it possible to perform the measurements in mice that spontaneously breathe room air. The organization of the work-flow in distinct work-areas reduces time delay and opens the possibility to simultaneously perform physiology experiments and harvest immune, heart and lung tissues.The procedural workflow outlined here can be adapted for a wide variety of laboratory settings and study designs, from small, targeted experiments, to large drug screening assays. The simultaneous acquisition of cardiac physiology data that can be expanded to include echocardiography^5,14-17 and harvest of heart, lung and immune tissues reduces the number of animals needed to obtain data that move the scientific knowledge basis forward. The procedural workflow presented here also provides an ideal basis for gaining knowledge of the networks that link immune, lung and heart function. The same principles outlined here can be adapted to study other or additional organs as needed.     

Monitoring of Systemic and Hepatic Hemodynamic Parameters in Mice

The use of mouse models in experimental research is of enormous importance for the study of hepatic physiology and pathophysiological disturbances. However, due to the small size of the mouse, technical details of the intraoperative monitoring procedure suitable for the mouse were rarely described. Previously we have reported a monitoring procedure to obtain hemodynamic parameters for rats. Now, we adapted the procedure to acquire systemic and hepatic hemodynamic parameters in mice, a species ten-fold smaller than rats. This film demonstrates the instrumentation of the animals as well as the data acquisition process needed to assess systemic and hepatic hemodynamics in mice. Vital parameters, including body temperature, respiratory rate and heart rate were recorded throughout the whole procedure. Systemic hemodynamic parameters consist of carotid artery pressure (CAP) and central venous pressure (CVP). Hepatic perfusion parameters include portal vein pressure (PVP), portal flow rate as well as the flow rate of the common hepatic artery (table 1). Instrumentation and data acquisition to record the normal values was completed within 1.5 h. Systemic and hepatic hemodynamic parameters remained within normal ranges during this procedure.This procedure is challenging but feasible. We have already applied this procedure to assess hepatic hemodynamics in normal mice as well as during 70% partial hepatectomy and in liver lobe clamping experiments. Mean PVP after resection (n= 20), was 11.41±2.94 cmH₂O which was significantly higher (P<0.05) than before resection (6.87±2.39 cmH₂O). The results of liver lobe clamping experiment indicated that this monitoring procedure is sensitive and suitable for detecting small changes in portal pressure and portal flow rate. In conclusion, this procedure is reliable in the hands of an experienced micro-surgeon but should be limited to experiments where mice are absolutely needed.     

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities

Opioid-induced hyperalgesia and tolerance severely impact the clinical efficacy of opiates as pain relievers in animals and humans. The molecular mechanisms underlying both phenomena are not well understood and their elucidation should benefit from the study of animal models and from the design of appropriate experimental protocols. We describe here a methodological approach for inducing, recording and quantifying morphine-induced hyperalgesia as well as for evidencing analgesic tolerance, using the tail-immersion and tail pressure tests in wild-type mice. As shown in the video, the protocol is divided into five sequential steps. Handling and habituation phases allow a safe determination of the basal nociceptive response of the animals. Chronic morphine administration induces significant hyperalgesia as shown by an increase in both thermal and mechanical sensitivity, whereas the comparison of analgesia time-courses after acute or repeated morphine treatment clearly indicates the development of tolerance manifested by a decline in analgesic response amplitude. This protocol may be similarly adapted to genetically modified mice in order to evaluate the role of individual genes in the modulation of nociception and morphine analgesia. It also provides a model system to investigate the effectiveness of potential therapeutic agents to improve opiate analgesic efficacy.