动物实验,动物血压 z-bo 2020-08-13 483

　　Blood pressure and electrocardiogram are important physiological indicators. Animal blood pressure and electrocardiogram measurement methods and techniques are one of the basic skills required for functional experimental education and one of the experimental techniques required by the Institute of Cardiovascular Physiology and Pharmacology.

　　This section introduces the methods and techniques of measuring blood pressure, indoor pressure and electrocardiogram of commonly used animals.

　　1. Measure the blood pressure of conscious rats

　　There are many ways to measure blood pressure in conscious rats. According to whether surgery is performed, it can be divided into invasive and non-invasive. According to the measurement method, it can be divided into direct and indirect, but direct methods are usually invasive. Direct methods are divided into transducers embedded in catheterization and abdominal telemetry. The catheter inserted into the rat’s artery is connected to the recording system through a transducer, thereby limiting the activity of the conscious rat during the measurement. There is no connection between the catheter in the latter artery and the transducer and recording system, allowing the rat to move freely during the measurement. Although indirect methods are usually non-invasive, there are many indirect methods, but the rat tail volume method and rat tail artery pulse pressure method are usually used. Currently, the most common blood pressure measurement method for awake rats is the rat tail artery pulse pressure method. The following mainly introduces the method of measuring the pulse pressure of the tail artery in rats. 1. Basic Principles When the pressure of the rat's tail exceeds the systolic pressure, the pulse disappears, and when the pressure drops to the systolic pressure, the pulse appears. When the diastolic blood pressure drops, the pulse returns to the pre-compression level. The instantaneous pressure when the pulse is detected and the change is the blood pressure value.

　　2. Experimental animals and equipment rats, weighing 150-300g, a tail pressure measuring system, which consists of a tail pressure gauge, a pulse sensor, a pressure tail cap, a tail heater and an animal fixing device.

　　3. There are some differences between the operating procedures of different manufacturers and different models of experimental methods and end-of-program pressure measurement systems, but the basic operating procedures are the same.

　　(1) Rat fixation and heating: Use local heating of the rat's body or tail to heat. Plexiglass fixing agent is usually used for fixing.

　　(2) Determine the initial pulse level. Place the pressure tail cuff and pulse sensor on the mouse tail in turn.

　　(3) Measure blood pressure: Inflate and pressurize with a rubber ball until the pulse is completely extinguished, increase the pressure of the pressurized tail cuff, continue to pressurize about 20mmHg, and then send a pulse signal to slowly deflate and evacuate until the level returns. At this time, the systolic blood pressure, diastolic blood pressure, mean arterial pressure and heart rate can be read from the pressure gauge or recording system. Generally, the measurement is performed three times in succession, and the average value is used as the measurement value.

　　4. Matters needing attention

　　(1) Awakening during the test Due to the limited activity of rats, fixed pressure will affect the accuracy of blood pressure. In order to reduce this effect, the rats must be trained to adapt before the formal experiment. In addition to the pressure measurement environment and operation methods, animal isolation can also make the animal quiet.. (2) Temperature will affect the relaxation of the rat tail artery, so the rat’s tail must be properly heated during the measurement. Usually controlled at about 34°C. The good time is 10 minutes.

　　(3) Practice shows that compressing the width and position of the tail cuff will affect the measurement. If the compression tail cuff is too small, the measured blood pressure value will be high, and its width will be too large, and vice versa. Therefore, the appropriate width of the compressed tail should be selected according to the weight of the animal. For weights less than 150 grams, the pressure tail cap is usually 1.5 cm, for a weight of about 200 grams, 2.0 cm is appropriate, and for a weight of more than 300 grams, 2.5-2.8 cm is appropriate.

　　The lower the compression tail sleeve is from the base of the rat's tail, the lower the blood pressure, so it is recommended to wear it on the base of the rat's tail. Likewise, each measurement must be in the same location.

　　(4) The decompression speed should be as constant as possible, because the decompression speed will affect the pressure reading.

　　2 Measurement of arterial blood pressure in anesthetized rats (direct measurement method)

　　There are two general methods for measuring arterial blood pressure in anesthetized rats. One is to use the common neck tube to measure blood pressure, and the other is to use the femoral artery cannula to measure blood pressure. blood pressure. Experimental animals and equipment rabbits weigh about 2 kg, and rats weigh about 200-250 grams. 20% carbamate injection or 1.5% phenobarbital sodium injection, 1% procaine injection, 0.3% heparin saline injection, a set of common laboratory equipment, rabbit or rat laboratory bench , Polyethylene medical plastic catheter for rabbits or rats (the outer diameter of rabbit catheter is 2mm, inner diameter is 1.5mm, the outer diameter of rat catheter is 1mm, inner diameter is 0.8mm), pressure sensor and its multi-channel physiological signal Acquisition and recording device.