Animal Models Core

导演从极其劳动密集的任务，创造 慢性动物和照顾他们的术后立即恢复。核心还将提供 在心力衰竭或假手术发生之前和期间对动物进行超声心动图评估 对照动物模型核心在过去10年的PPG中非常有效。 将由Dr. Kurtis G.或在其监督下制备各种动物模型。康沃尔语 具有多年的慢性动物实验经验，并在这些特定动物中具有丰富的经验 准备工作他将由三名技术人员协助在使用前准备和护理动物 PPG的投资者。本中心制备的模型为：（1）心脏冠状动脉结扎模型 （2）家兔心脏起搏心衰模型。 通过超声心动图评估所有动物的心脏状态。核心是 由两个超声心动图仪支持。兔成像在Accuson Sequoia 5120机器上进行， 啮齿动物图像在VisualSonicsVevo 770上获得。Johnnie Hackley女士主要负责 获得大鼠和家兔在诱导心力衰竭之前、期间和之后的数据。 a.动物模型的手术准备 1.心力衰竭大鼠模型：冠状动脉结扎。 将Sprague-Dawley大鼠（200 + g，雄性）随机分配至HF或假手术两组之一 动物心力衰竭动物的左冠状动脉将在其主动脉分叉附近结扎。 假手术组大鼠将接受相同的手术，但冠状动脉不会被结扎，与对照组一致。 我们和其他实验室使用的程序^'^'。将用2%异氟烷麻醉大鼠，并给予 6 pg阿托品/100 gm体重肌肉注射。将经口插入气管内导管， 正压通气将在左侧第4 "^肋间隙进行胸廓切开术。一旦 在插管后，剃除胸部毛发，用外科肥皂擦洗，然后涂上聚维酮碘。所有 在这个中心的手术将在严格的无菌程序下进行。HF组左冠状动脉 将用6 - 0脯氨酸缝线结扎，位于其从主动脉出口的下方，肺动脉流出道之间 束和左心房。在利加菲翁之前，将皮下注射0.5 mg利多卡因，以帮助有效预防 致命的心律失常充分的冠状动脉闭塞将通过心脏扩大和苍白来证明。 心肌然后将胸管插入6 '*^肋间隙并在其下方0.5厘米处退出 点在这些操作之后，胸腔将关闭并排空。当老鼠开始呼吸时 胸腔内的液体和空气会自然排出，胸管会被移除。对照组大鼠将 接受开胸手术和心脏操作，用利多卡因治疗，但冠状动脉结扎不会 被安置。在动物开始显示出恢复迹象后，将移除气管内导管， 使大鼠从麻醉中恢复。然后将大鼠置于单独的笼中，直至 实验当天。 将大鼠圈养在具有12小时光照-黑暗循环的房间中，环境温度维持在 22 º C和30 - 40%的湿度。实验室食物（Purina）和自来水可自由饮用。在我们 而且，对于梗塞大鼠，初始（立即或24小时）死亡率为21%。完成后 在手术中，将用镇痛剂对大鼠进行镇痛治疗：1.恢复前约45分钟 从麻醉剂开始，将以0.05mg/kg的剂量给予大鼠丁丙诺啡; 2.然后他们会收到 布丙诺啡0.05 mg/kg SQ，每12小时一次。这将在术后前2天进行。大鼠将 在实验方案规定的时间交付给PI。 234

Directors from the extremely labor intensive task of creating chronic animals and caring for their immediate post operative recovery. The Core will also provide echocardiographic assessment on animals prior to and during the development of heart failure or sham fime controls. The Animal Models Core has worked very effectively over the past 10 years of this PPG. Various animal models will be prepared by or under the supen/ision of Dr. Kurtis G. Cornish who has had many years of experience in the preparafion of chronic animals and is experienced in these specific animal preparations. He will be assisted by three technicians in the preparation and care of animals prior to their use by the PPG invesfigators. The models prepared by this Core will be (1) the coronary ligafion model of heart failure (HF) in the rat, and (2) the pacing model of HF in the rabbit. Assessment of the cardiac status of all animals is obtained echocardiographically. The Core is supported by two echocardiographs. Rabbit imaging is done on an Accuson Sequoia 5120 machine and rodent images are obtained on a Visual Sonics Vevo 770. Ms. Johnnie Hackley is primarily responsible for obtaining the data on the rats and rabbits prior to, during and after the inducfion of heart failure. A. Surgical Preparation of Animal Models 1. Rat model of heart failure: coronary ligation. Sprague-Dawley rats (200+ g, males) will be assigned randomly to one of two groups, HF or sham animals. The heart failure animals will have their left coronary artery ligated near its bifurcafion from the aorta. Sham rats will undergo the same surgery but the coronary arteries will not be tied, consistent with the procedure used by us and by other laboratories^'^¿. The rat will be anesthefized with 2% Isoflurane and given 6 pg atropine/100 gm body weight im. An endotracheal tube will be inserted orally in order to administer positive pressure ventilation. A thoracotomy will be done at the 4"^ intercostal space on the left side. Once intubated, the chest will be shaved and scrubbed with surgical soap and then painted with Betadine. All surgeries in this Core will be done following strict sterile procedures. In the HF group, the left coronary artery will be ligated with 6-0 Proline suture, just below its exit from the aorta, between the pulmonary artery outflow tract and left atrium. Prior to the ligafion, 0.5 mg of lidocaine will be injected SQ to help prevent potenfially lethal arrhythmias. Adequate coronary occlusion will be evidenced by cardiac enlargement and blanching of the myocardium. A chest tube will then be inserted in the 6'*^ intercostal space and exited 0.5 cm below this point. Following these maneuvers the thorax will be closed and evacuated. As the rats begin to breathe spontaneously, the fluid and air in the chest will be evacuated and the chest tube removed. Control rats will undergo thoracotomy and the manipulafion of the heart, treated with lidocaine, but the coronary ligature will not be placed. After the animal begins to show signs of recovery, the endotracheal tube will be removed and the rats will be allowed to recover from the anesthesia. The rats will then be placed in individual cages until the day of the experiment. The rats will be housed in a room with a 12-hour light-dark cycle, an ambient temperature maintained at 22¿C and humidity of 30-40%. Laboratory chow (Purina) and tap water will be available acf libitum. In our hands there is an inifial (immediately or 24 hour) mortality rate of 21% for the infarcted rats. After completion of surgery the rats will be treated prophylactically with analgesics: 1. approximately 45 minutes before recovery from the anesthetic the rats will be given Buprinorphine at a dose of 0.05 mg/kg; 2. Then they will receive Buprinorphine 0.05 mg/kg SQ every 12 hours. This will be done for the first 2 post-operative days. Rats will be delivered to the PI at the time prescribed by the experimental protocol. 234