JPS5831532Y2 - Pulse wave measuring device for rats - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a measuring device for measuring the pulse waves of rats such as 20-day rats, hamsters, and guinea pigs, that is, the waves imparted to blood flow by the pulsations of arterial walls.

Such measurement of pulse waves of rats is necessary in animal experiments, and it is necessary to measure a large number of rats. Therefore, it is desired that the pulse waves can be easily measured.

This measurement of the rat's pulse wave is used, for example, to measure the rat's blood pressure.

To measure a rat's blood pressure, wrap a cuff around the rat's tail, apply air pressure to the cuff, tighten the cuff to stop blood flow to the tail, then gradually loosen the cuff and measure the flow of blood to the tail. By doing this, you can do what you do.

Conventionally, a pressure detector was placed in contact with the tail of the animal, and the pulse wave was detected by detecting the change in pressure from the state in which the blood stopped to the state in which it began to flow.

However, the rat's tail itself has a small volume: the total amount of blood it occupies is also significantly smaller.

Therefore, it has been extremely difficult to accurately detect the state in which the blood is flowing out.

Therefore, in order to facilitate this detection, test rats were warmed to improve blood flow throughout the body, making it easier to detect blood flow in the tail area.

However, it is difficult to do this for a large number of rats.

Since the amount of blood indoors is small, the flow rate of blood from the blood vessels flowing out is also low, making it difficult to detect.Moreover, since it is a living animal, there is a risk of making noises when the tail moves, and other surroundings. Noise may also be introduced due to vibrations, etc., making accurate detection difficult.

This invention provides a pulse wave measuring device for rats that can relatively easily and accurately detect the pulse waves of a large number of rats.

Hereinafter, an embodiment of the pulse wave measuring device for rats according to this invention will be described with reference to the drawings.

As shown in FIG. 1, the main body 11 is in the form of a rectangular parallelepiped block, and is preferably made of a conductive material that easily conducts heat, such as aluminum.

A hole 12, which is an insertion hole into which a rat's tail is inserted, is formed in the main body 11.

A light source 1 is placed on one side of the main body 11 with the hole 12 in between.
3 is provided as shown in FIG.

That is, a through hole 15 is formed substantially perpendicularly to the hole 12, and within the through hole 15, the light source 13 is arranged above the hole 12, and the light receiving element 14 is arranged inside the hole 12. .

Furthermore, in this example, the main body 11 is divided into upper and lower halves at the position of the hole 12 so that the inside of the hole 12 can be easily cleaned, and is configured to be separable into an upper half 16 on the upper side and a lower half 7 on the lower side. Ru.

That is, these upper half 16 and lower half 17 are combined,
Further, a fixing plate 18 is provided on the upper surface of the main body 11.

For this installation, a screw 21 is inserted through the plate 18, passes through the upper half body 16, and reaches the lower half body 17. body 1
6.17 are fixed to each other.

Further, a back cover 19 is brought into contact with the bottom surface of the lower half body 17 and similarly fixed to the lower half body 17 with screws 22, and the through hole 15 is closed by the back cover 19.

For mounting, a hole is formed in the center of the plate 18, and one end of the lamp socket 23 is fixed to the periphery of the hole with a screw 24.

The lamp socket 23 is fitted and inserted into the through hole 15, the light source 13 is held within the lamp socket 23, and a condensing lens 25 is attached to the inner end, that is, the lower end.

The lens 25 and the light receiving element 14 are close to the inner peripheral surface of the hole 12.

A cable holder 26 is attached to the side surface of the main body 11.

A cable 27 is held by the cable holder 26, and a light source lead wire 28 that reaches the light source 13 in the lamp kerato is drawn out from the cable 27, and a lead wire 29 that reaches the light receiving element 14 is drawn out, and the lead wire 29 is placed under the main body. half body 1
It passes inside through a small hole formed in 7 and is connected to the light receiving element 14 .

Furthermore, the shield wire 31 of the cable 24 is connected to the cable holding part 2.
6 is tightened by the fastener 32 that stops the fastener 32.
tightens the holding portion 27 to the main body 11 and electrically connects the main body 11 and the shielded wire 31.

The hole 12 through which the rat's tail is inserted has an insertion end 12 a that matches the thickness and shape of the tail, and an exit end 12 a.
It is preferable to make the hole larger than b, for example, the diameter on the 12a side is 7 mm and the diameter on the 12b side is 6 mm, or the hole is tapered such that the diameter on the 12a side is 9 mm and the diameter on the 12b side is 8 mm. .

Further, from the viewpoint of improving sensitivity, a PIN photodiode with a high SN ratio is suitable as the light receiving element 14.

Furthermore, it is preferable to select and use, for example, a tungsten lamp as the light source 13 so as to irradiate the light onto the light receiving element and at the same time heat the main body 11 with heat from the light source to warm the tail inserted into the hole 12.

For example, as shown in FIG. 3, a rat 35 is immovably placed in a cage 34, and its tail 36 is inserted into the hole 12 of the main body 11 of the pulse wave measuring device according to this invention.

In this state, a cuff 37 is wrapped around the tail 36, and air pressure is applied to the cuff 37 from the air tank 38, thereby blocking the blood flow in the tail 36.

Thereafter, the air pressure in the cuff 37 is gradually relaxed.

The output of the light receiving element 14 is amplified by the amplifier 38 and the recorder 39
as a recording signal.

At the same time, the pressure in the air tank 38 is detected by the sensor 41, the detected output is amplified by the amplifier 42, the amplified output is converted into a digital signal by the AD converter 43, and this is sent to the print header 45 through the printing section 44. The voltage is applied and recorded on the same recording paper 46 of the recorder 39.

As a result, a record 47 of the pulse wave on the recording paper 46 and a record 48 of the cuff pressure at that time are obtained.

From this recorded state, blood pressure can be measured by determining the pressure at which blood begins to flow based on changes in the intensity of light transmitted through the tail 36 of the rat I in response to changes in cuff pressure detected by the light receiving element 14. can.

As described above, according to the pulse wave measuring device for rats according to this invention, the tail of the rat is inserted into the hole of the main body 11, and the tail is fixed in that state to the extent that it cannot move due to the weight of the main body 11. Moreover, since the tail is fitted into the hole 12, the tail cannot move, and the length of the hole 12 is sufficient to block light from the outside, so that the light receiving element 14 does not receive outside light, that is, background noise. It is selected so that it does not intrude, makes it easy to measure, and is not easily affected by tail movements or external vibrations.

In particular, by using a heat-generating lamp such as a tungsten lamp as the light source and using a material with good thermal conductivity as the main body 11, the inserted tail is warmed, which makes it easier for blood to flow, making it easier to perform measurements. .

In addition, when the main body 11 is made to be able to be disassembled into two parts as in this example, scale-like substances attached to the rat may adhere to the inside of the hole 12 after multiple uses, but they can be easily cleaned. can do.

Furthermore, if the main body 11 is made of a material with good thermal conductivity and a heat generating light source is used, it is possible not only to warm the tail as described above, but also to ground the shield wire of the cable to this main body. It is possible to easily obtain a device that is not easily affected by noise.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an example of the pulse wave measuring device for rats according to this invention, Fig. 2 is a sectional view taken along the line A-A, and Fig. 3 is an example in which the measuring device of this invention is applied to blood pressure measurement in rats. FIG. 11: Main body, 12: Hole, 13: Light source, 14: Light receiving element,
27: Cable, 25: Lens.

Claims (1)

[Scope of utility model registration request] An insertion hole is formed between opposing side plates of the main body made of a thermally conductive material, and has a shape that allows a rat's tail to fit and pass smoothly from one side to the other. A through hole is formed at a substantially intermediate position of the insertion hole at right angles to the longitudinal direction of the insertion hole, and a through hole is formed at a right angle to the longitudinal direction of the insertion hole across the upper and lower half of the body. A heat generating light source is installed in the through hole, a condensing lens is disposed at the end of the light source on the side of the insertion hole, and the condensing lens is disposed in the through hole of the lower half. A light receiving element for receiving light from the light source is attached to the main body, and a fixing means for fixing the upper half and the lower half to each other is provided between the upper half and the lower half. is attached with a presser that holds a cable incorporating a power supply line for the light source and a detection line for the light receiving element, and connects the shielded wire of this cable to the main body, and prevents conduction heat from the main body and the light condensing. The tail of the rat held in the insertion hole is warmed by radiant heat through the lens, improving blood circulation, and the transmitted light received by the light receiving element warms the tail of the held rat. The light source is selected so that the wave can be measured, and the length of the insertion hole is set to a value sufficient to block external light leakage at the detection position of the light receiving element. Measuring instrument.