Development Of Compound Anesthetic MZ

With the development of medical and bioscientific research in our country,animal experiments have become more and more important,especially the rodent experimental animals.The treatment in the rodent experimental animals such as embryo transplantation,purification,surgery,treatment,blood collection and disease model,etc.needs proper anesthesia.There are some disadvantage of anesthetize rodent experimental animals with a single drug,for example:increased cardiac burden(heart rate slows,faster or rhythm disorders),decreased vital capacity,easy peripheral circulation slowed down,low temperature death,etc.Currently,there are some shortages of anesthesia drugs,such as narrow safety range,shallow depth of anesthesia and strong side effects.Inhalation anesthesia for rodent required expensive respirator and inhaled anesthetics,and gas a nesthesia machine need regular maintenance and the anesthesiologist needs training to detect and maintain anesthesia.In addition,some special animal models could not use inhalation ane sthesia.Therefore,it has become urgency to explore a new composite a nesthetic for rodent experimental animals.So it is need more careful to develop preferable narcotic drugs.Based on the theories of balanced anaesthesia of animals,we developed a proper compound injection,which contains there widely used anesthetics:Ketamine,Xylazine and Dexmedetomidine,named-MZ compound anesthesia.This study contained the following 3parts.Research on Prescription of MZ Injection:Based on the results of pre-experiment,according to the factors that affect the anesthetic effect,ort hogonal method was used,the concentrations of Ketamine,Xylazine and Dexmedetomidine were selected as variable factors and table L9(3~3)was used to do experiment on the basis of loss of righting reflex in C57BL/6 mouse with SPF grade.The optimum prescription was:Ketamine(55mg/kg),Dexmedetomidine(1mg/kg)and Xylazine(10mg/kg).named as MZ injection.The manufacturing process is simple,which is suitable for mass production.Safety Evaluation and Long-Term Stability of MZ Injection:To evaluate the safety of MZ injection,acute toxicity experiment was carried out in mice by up-and-down method,the results showed that ED50=21mg?kg-1 body weight,LD50=164mg?kg-1 body weight,AI=7.81 Injecting MZ into rabbits to carry out local irritat ion experiment,the results indicated that MZ had mild vein irritation and slight muscle irritation,did not cause eye irritation.To establish expiration time for MZ injection,long term test was performed,the results showed that the main compositions of MZ injection were stable,the injection looked clear,no impurity,the period of validity was 16 months at room temperature,protect from light.Anesthetic Effect of MZ Injection in Rat:This study was investigated in 5 Rats.,the animals were injected with MZ injection(0.006ml/kg)without premedication,to observe the time to induction,maintenance,recovery,heart rate,SPO2,respiration rate,systolic pressure,diastolic pressure,ractal temperature,effects of analgesia,sedative and muscle relaxation.The time to induction,maintenance,recovery were3.86±1.14a,43.23±6.56a,5.11±1.32a,respectively;heart rate,SAP and DAP increased slowly with a peak,then decreased steadily but rema ined within the normal range;rectal temperatures decreased slowly but did not vary significantly during induction and maintence of anesthesia;respiratory rate decreased rapidly at first and then increased slowly;no vomiting,nystagmus,excessive salivation.In conclusion,the MZ injection is a potential good surgical anesthesia for rodent experimental animals.