实验动物,动物麻醉 z-bo 2022-02-05 434

　　Laboratory anesthesia for experimental animals is a complex working system. The correct anesthesia treatment is a powerful guarantee for successful animal testing. Inadequate anesthesia treatment can lead to errors, and it is difficult to analyze with experimental results. In order to obtain a good anesthesia effect, please master the basic knowledge and technology of laboratory animal anesthesia, and follow the scientific anesthesia procedures and various factors that affect laboratory animal anesthesia (animal factors, environmental factors, etc.). ) Still need to understand.

　　1. Animal factors

　　1, 1 age and weight

　　The response of animals to drugs varies with age. Someone divided rats and mice into three groups (young, adult, and old) and observed the effect of age on the acute toxicity of ethanol, pentane and dichloroethane. The observation results of LD50 and anesthetic concentration show that for young adults and old people. The age difference for toxic substances may be related to the activity of toxic enzymes. Small animals lack these enzymes, so they are very prone to substance poisoning. The detoxification enzymes of newborn rats reach levels about 8 weeks after the birth of adult rats. The rat glucuronide converting enzyme reaches the adult rat level about 30 days after birth. In addition, young animals, especially newborn animals, have poor liver and kidney function and low drug excretion capacity, which increases the amount of free drugs and drugs that enter the tissues, making them more prone to accumulation and poisoning. Small animals have higher basal metabolism per unit body weight, so the dose of anesthetic per unit body weight of small animals is higher. In some long-term experiments, the observation time is longer, and you can choose smaller and smaller animals for the experiment.

　　1, 2 gender

　　Experiments have shown that animals of different sexes have different sensitivity to the same drug and have different responses to different stimuli. Female animals have different stages of the sexual cycle during pregnancy and lactation, and have different physical responses. Therefore, the main change is that men or women are usually preferred for experiments. The basal metabolic rate of men is higher than that of women, and women's metabolic rate increases during pregnancy and is more sensitive to drugs. For example, gelatin can be used in male rats aged 5 to 6 weeks and has analgesic effect, but when administered to female rats, it has no analgesic effect. Calculating the intake and excretion of ethanol in 3-month-old lWistar rats per unit body weight, females are more than males. 1, 3 Physiology and Health Lean muscle animals need more anesthetics than fat animals because the basal metabolic rate of relatively non-metabolizable tissues is lower. Yes. Activity can increase the rate of metabolism, thereby increasing the amount of anesthesia required for moving animals. Poor animals need a small amount of anesthetic and low tolerance. Easy to poison. Dogs with insufficient food intake or weight loss of 10% to 20% will significantly extend the duration of anesthesia.

　　1,4 animals

　　Ensuring proper nutrition is an important factor in maintaining animal health, and the relationship between feed and animals is closer. Animal growth, development, reproduction, ability to resist disease and all important activities depend on nutritious diet. Animals should be placed one week before anesthesia, and they should be fed carefully and managed to stay healthy. You should provide nutritionally balanced feed, and no too much or too little nutrition. For example, the basal metabolic rate of succulent dogs can be increased by 90%. The protein content of mouse feed is less than 20%, which can easily cause intestinal diseases. Vitamin deficiency in guinea pig feed can easily cause scurvy.

　　2, environmental factors

　　2, a temperature

　　Within a certain range, the temperature changes slowly, and the body can adjust automatically. However, unpredictable changes may be too large or too rapid to adversely affect your physical behavior and physiology. Therefore, if the experimental environment is too hot or too cold, your body's resistance will decrease, your sensitivity to anesthetics will increase, and you are more likely to be poisoned. Therefore, it affects the anesthesia effect.

　　2, 2 humidity

　　If the humidity is too high, microorganisms are easy to grow, if the humidity is too low (less than 40%), dust is easily scattered, which is harmful to animal health. The relative humidity of the air is also closely related to the regulation of animal body temperature. This effect is particularly obvious under high temperature conditions. For example, when the humidity is less than 40%, mice are prone to scurvy, while under low humidity conditions, lactating mice or female mice are more likely to eat their children. Humidity directly affects the animal's temperature regulation and health, and indirectly affects the animal's ability to respond to anesthetics. Therefore, in an animal anesthesia laboratory, the relative humidity should be between 40% and 70%, preferably 50% ± 5%.

　　2, 3 air circulation and cleaning

　　Air circulation has a significant impact on animals, because laboratory animals usually have a larger body surface area per unit weight than humans. On the other hand, wind speed will affect the heat dissipation of the animal's body surface, especially the temperature of the animal under anesthesia. On the other hand, proper air flow can quickly exhaust dirty gases in the laboratory, such as ammonia. Experiments have shown that in the air around experimental animals, excessive ammonia can irritate the mucous membranes of the animals, causing lacerations and coughing. Therefore, the air in the animal anesthesia laboratory should be kept as fresh as possible, the ammonia concentration should be less than 20 mg/L, the air flow rate should be 10-25 cm/sec, and the air exchange frequency should be 8-15 times/hour. is compulsory. Avoid winter draughts. In other words, animals and environmental factors directly or indirectly affect animal health, and their ability to clear metabolic enzymes and anesthetics in their bodies is different, so their sensitivity to anesthetics is different. Therefore, when giving animals anesthesia, it is necessary to fully consider the above factors, and increase or decrease the dose as needed to obtain an appropriate anesthetic effect.