Constant-pressure perfusion device for improved in-vitro frog heart

Abstract

The constant-pressure perfusion device comprises a bottom plate, a first lead screw, a second lead screw and a third lead screw are arranged on the two sides of the top of the bottom plate and the rear end of the center of the bottom plate respectively, the tops of the first lead screw, the second lead screw and the third lead screw are all connected with adjusting knobs, and a lifting seat is arranged at the position, close to the top, of the surface of the first lead screw. A first lifting frame is in threaded connection with the top of the surface of the second lead screw, and a second lifting frame is in threaded connection with the bottom of the surface of the third lead screw. According to the constant-pressure perfusion device for improving the in-vitro frog heart, through the design of a first lead screw, a second lead screw, a third lead screw, a lifting seat, a first lifting frame, a second lifting frame, a guide rod and an adjusting knob, an experimenter can rotate the adjusting knob according to the thread transmission principle, so that the lifting seat and the first lifting frame move up and down along the lead screws; therefore, the purpose of accurately controlling the heights of the liquid storage bottle, the frog heart, the venous cannula and the arterial cannula is achieved, the adjusting mode is high in accuracy, and the experiment efficiency and accuracy are improved.

Description

Technical Field

[0001] This utility model relates to the field of constant pressure irrigation technology for isolated frog hearts, specifically an improved constant pressure irrigation device for isolated frog hearts. Background Technology

[0002] Constant pressure perfusion of isolated frog hearts is a biological experimental technique that involves maintaining the heart of a frog (such as a bullfrog) in a constant pressure environment while it is in situ, and providing the heart with a physiological solution (such as Ringer's solution) that simulates the internal environment through artificial perfusion to maintain its rhythmic excitation and contraction activities for a certain period of time.

[0003] Existing constant-pressure perfusion devices for isolated frog hearts have a significant drawback in experimental applications: the height of the reservoir bottle is difficult to adjust, making operation inconvenient and hindering effective regulation of the load borne by the heart before contraction. This makes it difficult for researchers to ensure a constant and appropriate pressure of perfusion fluid supply to the isolated frog heart during experiments, thus affecting the accuracy and reliability of experimental results. Furthermore, researchers often struggle to quickly and accurately adjust to the ideal state within a short timeframe, increasing the difficulty of experimental operation and limiting experimental efficiency. Moreover, the bottom of existing reservoir bottles is conical, requiring them to be filled at least halfway with physiological solution, which is wasteful. Reducing the liquid level in the reservoir bottle makes it impossible to maintain the load borne by the heart before contraction. Existing devices cannot ensure that the arterial and venous cannulas and the heart are at the same level. The horizontal arrangement of the bottom tube in existing devices makes it difficult to collect fluid at the outlet. Utility Model Content

[0004] This invention provides an improved constant pressure perfusion device for isolated frog hearts. The height of the liquid level in the glass tube can be precisely controlled by adjusting the liquid storage bottle, and the arterial and venous cannulas and the heart are kept at the same level. This facilitates experimental operation, effectively adjusts the load borne by the heart before contraction, and has high accuracy.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a modified constant pressure perfusion device for isolated frog hearts, comprising a base plate, wherein a first lead screw, a second lead screw, and a third lead screw are respectively provided on the top two sides and the rear end of the center of the base plate, and an adjustment knob is fixedly connected to the top of each of the first lead screw, the second lead screw, and the third lead screw; a lifting seat is provided near the top of the surface of the first lead screw, a first lifting frame is threadedly connected near the top of the surface of the second lead screw, and a second lifting frame is threadedly connected near the bottom of the surface of the third lead screw; guide rods are fixedly installed on both sides of the rear end of the top of the base plate, and the upper ends of the two guide rods pass through the exterior of the second lifting frame and the first lifting frame and the lifting seat in sequence; a placement groove is provided near the front end of the center of the lifting seat, and a flat-bottomed liquid storage bottle is placed inside the placement groove.

[0006] At the rear end of the second lifting frame near the lifting seat, a vertical plate is fixed on the base plate, and a vertical glass tube is mounted on the vertical plate; the lower end of the liquid storage bottle is fixedly connected to one end of a flexible tube, and the other end of the flexible tube is connected to a transverse interface on one side of the lower end of the glass tube. The length of the flexible tube is sufficient for the movement stroke of the lifting seat; the transverse interface on the other side of the lower end of the glass tube is connected to one end of another flexible tube, and the other end of the flexible tube is connected to an intravenous catheter. At the connection between the flexible tube and the intravenous catheter, a water-stopping clamp is installed on the flexible tube.

[0007] A vertical pipe is fixedly connected to one side of the first lifting frame near the front end. A side pipe is fixedly connected to one side of the vertical pipe, and a horizontal pipe is fixedly connected to the lower end of the vertical pipe. At the end of the horizontal pipe away from the side pipe, the horizontal pipe is connected to one end of another flexible tube, and the other end of the flexible tube is connected to an arterial cannula.

[0008] Furthermore, the lower ends of the first lead screw, the second lead screw, and the third lead screw are respectively movably connected to three bearings fixedly installed at the rear end of the top of the base plate.

[0009] Furthermore, the adjustment knob is designed with a cylindrical structure, and the surface of the adjustment knob is provided with anti-slip vertical grooves.

[0010] Furthermore, the lifting seat is connected to the surface thread of the first lead screw through a threaded groove opened at the front end of one side.

[0011] Furthermore, the first lifting frame is connected to the surface thread of the second lead screw through a threaded groove on one side of its rear end.

[0012] Furthermore, the first lifting frame is connected to the surface thread of the second lead screw through a threaded groove on one side of its rear end.

[0013] Furthermore, on the side closer to the side tube, this end of the horizontal tube slopes downwards.

[0014] Furthermore, the glass tube is equipped with graduation lines.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] This improved constant-pressure perfusion device for isolated frog hearts utilizes a design consisting of a first lead screw, a second lead screw, a third lead screw, a lifting seat, a first lifting frame, a second lifting frame, a guide rod, and an adjusting knob. Employing the principle of threaded transmission, the experimenter can easily rotate the adjusting knob to move the lifting seat and the first lifting frame up and down along the lead screw, thereby achieving precise control of the height of the reservoir and arterial cannula. This adjustment method is not only highly accurate but also simple to operate, greatly improving experimental efficiency and accuracy. By adjusting the third lead screw, the experimenter can quickly and precisely adjust the second lifting frame, ensuring that the arterial and venous cannulas and the heart are at the same level. The reservoir position changes with the height of the lifting seat. It can effectively regulate the load borne by the heart before contraction, thereby ensuring the accuracy and reliability of experimental results and ensuring that the frog heart maintains a stable posture during the experiment. This not only improves the flexibility of the experiment but also helps to reduce experimental errors. At the same time, the guide rod enhances the stability of the device, ensuring smooth movement of the lifting seat, the first lifting frame, and the second lifting frame during adjustment. The flat-bottomed liquid storage bottle is easy to adjust and can better maintain the height of the preload. As the cardiac output increases, the preload will not decrease significantly, and it can save on drugs, requiring only 1 / 3 of the physiological solution. The downward tilt of the outlet end of the horizontal tube facilitates the smooth collection of liquid. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Figure 2 This is a three-dimensional structural view of the lifting seat of this utility model.

[0019] Figure 3 This is a three-dimensional structural view of the first lifting frame of this utility model.

[0020] In the diagram: 1. Base plate; 2. First lead screw; 3. Second lead screw; 4. Third lead screw; 5. Lifting seat; 6. First lifting frame; 7. Second lifting frame; 8. Guide rod; 9. Adjusting knob; 10. Vertical tube; 11. Side tube; 12. Horizontal tube; 13. Flexible tube; 14. Arterial cannula; 15. Water stop clamp; 16. Storage bottle; 17. Intravenous cannula; 18. Vertical plate; 19. Glass tube. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figure 1-3 An improved constant pressure perfusion device for isolated frog hearts includes a base plate 1. A first lead screw 2, a second lead screw 3, and a third lead screw 4 are respectively provided on the top two sides and the rear end of the center of the base plate 1. Adjustment knobs 9 are fixedly connected to the top of the first lead screw 2, the second lead screw 3, and the third lead screw 4. A lifting seat 5 is provided near the top of the surface of the first lead screw 2. A first lifting frame 6 is threadedly connected near the top of the surface of the second lead screw 3. A second lifting frame 7 is threadedly connected near the bottom of the surface of the third lead screw 4. Guide rods 8 are fixedly installed on both sides of the rear end of the top of the base plate 1. The upper ends of the two guide rods 8 pass through the exterior of the second lifting frame 7, the first lifting frame 6, and the lifting seat 5 in sequence. A placement groove is opened near the front end of the center of the lifting seat 5. A flat-bottomed liquid storage bottle 16 is placed inside the placement groove.

[0023] At the rear end of the second lifting frame 7 near the lifting seat 5, a vertical plate 18 is fixed on the base plate 1, and a vertical glass tube 19 is mounted on the vertical plate 18; the lower end of the liquid storage bottle 16 is fixedly connected to one end of a flexible tube 13, and the other end of the flexible tube 13 is connected to a transverse interface on one side of the lower end of the glass tube 19. The length of the flexible tube 13 meets the travel of the lifting seat 5; the transverse interface on the other side of the lower end of the glass tube 19 is connected to one end of another flexible tube 13, and the other end of the flexible tube 13 is connected to an intravenous catheter 17. At the connection between the flexible tube 13 and the intravenous catheter 17, a water-stopping clamp 15 is provided on the flexible tube 13.

[0024] A vertical pipe 10 is fixedly connected to one side of the first lifting frame 6 near the front end. A side pipe 11 is fixedly connected to one side of the vertical pipe 10. A horizontal pipe 12 is fixedly connected to the lower end of the vertical pipe 10. At the end of the horizontal pipe 12 away from the side pipe 11, the horizontal pipe 12 is connected to one end of another flexible tube 13. The other end of the flexible tube 13 is connected to an arterial cannula 14.

[0025] The lower ends of the first lead screw 2, the second lead screw 3, and the third lead screw 4 are respectively movably connected to three bearings fixedly installed at the rear end of the top of the base plate 1, providing rotational support for the first lead screw 2, the second lead screw 3, and the third lead screw 4.

[0026] The adjustment knob 9 has a cylindrical structure and anti-slip vertical grooves on its surface, which serves to prevent slipping.

[0027] The lifting seat 5 is connected to the surface thread of the first lead screw 2 through a threaded groove on one front side. By rotating the first lead screw 2, the lifting seat 5 can be adjusted to move up and down.

[0028] The first lifting frame 6 is connected to the surface thread of the second lead screw 3 through a threaded groove on one side of its rear end. The height of the first lifting frame 6 can be easily adjusted by rotating the second lead screw 3.

[0029] The second lifting frame 7 is connected to the surface thread of the third lead screw 4 through a threaded groove at the center of its rear end. A connecting ring is fixedly connected to the front surface of the second lifting frame 7, and the height of the second lifting frame 7 can be easily adjusted by rotating the third lead screw 4.

[0030] On the side near the side tube 11, this end of the horizontal tube 12 slopes downwards, making it easier to collect the liquid as it flows out of the horizontal tube 12.

[0031] The glass tube 19 is equipped with graduation lines for easy observation of liquid volume.

[0032] Working Principle: The device achieves precise control of key components through a precisely designed threaded transmission system. At the start of the experiment, the experimenter first uses the second lifting frame 7 on the base plate 1 to dissect the frog, obtaining and properly placing the isolated frog heart. Then, the height of the arterial cannula 14 and the second lifting frame 7 is adjusted by rotating the adjusting knob 9 of the second lead screw 3. Utilizing the threaded connection principle, this moves the first lifting frame 6 and its connected vertical tube 10, side tube 11, horizontal tube 12, and arterial cannula 14 up and down as a whole, achieving precise control of the height of the arterial cannula 14. Furthermore, by rotating the adjusting knob 9 of the third lead screw 4, the height of the second lifting frame 7 can be precisely adjusted so that the height of the arterial cannula 14 matches the height of the venous cannula 17. Once the second lifting frame 7 is adjusted to a suitable position between the heights of the arterial cannula 14 and the venous cannula 17, the isolated frog heart is placed. On the second lifting frame 7, the arterial cannula 14 and the venous cannula 17 are connected to the frog heart, respectively. Then, by rotating the adjustment knob 9 on the top of the first lead screw 2, the lifting seat 5 is driven to move up and down along the first lead screw 2, thereby precisely adjusting the height of the reservoir bottle 16. The change in the height of the reservoir bottle 16 can effectively adjust the preload. The preload is the load that the heart bears before contraction, which represents the amount of blood returning to the heart. That is to say, if the liquid level in the glass tube 19 is higher, the amount of blood returning to the heart is greater. Therefore, this adjustment process can ensure the stability of the perfusion flow of the frog heart during the experiment and avoid experimental errors caused by improper height. During the entire adjustment process, the guide rods 8 play a key stabilizing role. They pass through the lifting seat 5, the first lifting frame 6 and the second lifting frame 7, ensuring the smooth movement of these components during the adjustment process and preventing experimental failures caused by shaking or tilting.

[0033] Because of the differences in frog species and individual characteristics, the height of the second lifting frame 7 needs to be adjusted for each experiment. The flat-bottomed reservoir 16 is easy to adjust and can better maintain the preload height, meaning that the preload will not decrease significantly with the output of cardiac output, and it can save drugs. The original conical reservoir required at least half full of physiological solution, but after changing the shape, only 1 / 3 of the physiological solution is needed. The downward tilt of the outlet end of the horizontal tube 12 helps to collect the liquid smoothly when it flows out, and the scale on the glass tube 19 makes it easy to observe the liquid volume. The length of the flexible tube 13 meets the travel of the reservoir 16 and does not affect the change of the height position of the reservoir 16. The height of the liquid level in the reservoir 16 represents the perfusion pressure, and the scale on the glass tube 19 connected to the reservoir 16 can show the height of the liquid level from the frog's heart, representing the magnitude of the ventricular preload. The height of the liquid level in the reservoir 16 and the height of the liquid level in the glass tube 19 are at the same level, and the reservoir 16 and the glass tube 19 are connected by a flexible tube 13, which is a communicating vessel.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A modified constant-pressure perfusion device for isolated frog hearts, comprising a base plate (1), characterized in that: The bottom plate (1) is provided with a first lead screw (2), a second lead screw (3) and a third lead screw (4) on the top two sides and the rear end of the center, respectively. The top of the first lead screw (2), the second lead screw (3) and the third lead screw (4) are all fixedly connected with an adjustment knob (9); a lifting seat (5) is provided on the top of the surface of the first lead screw (2), a first lifting frame (6) is threaded on the top of the surface of the second lead screw (3), and a second lifting frame (7) is threaded on the bottom of the surface of the third lead screw (4); guide rods (8) are fixedly installed on both sides of the rear end of the top of the bottom plate (1). The upper ends of the two guide rods (8) pass through the outside of the second lifting frame (7) and the first lifting frame (6) and the lifting seat (5) in sequence. A placement groove is opened at the front end of the center of the lifting seat (5), and a flat-bottomed liquid storage bottle (16) is placed inside the placement groove. At the rear end of the second lifting frame (7) near the lifting seat (5), a vertical plate (18) is fixed on the base plate (1), and a vertical glass tube (19) is mounted on the vertical plate (18); the lower end of the liquid storage bottle (16) is fixedly connected to one end of a flexible tube (13), and the other end of the flexible tube (13) is connected to the transverse interface on one side of the lower end of the glass tube (19). The length of the flexible tube (13) meets the travel of the lifting seat (5); the transverse interface on the other side of the lower end of the glass tube (19) is connected to one end of another flexible tube (13), and the other end of the flexible tube (13) is connected to the intravenous catheter (17). At the connection between the flexible tube (13) and the intravenous catheter (17), a water-stopping clamp (15) is provided on the flexible tube (13). A vertical pipe (10) is fixedly connected to one side of the first lifting frame (6) near the front end. A side pipe (11) is fixedly connected to one side of the vertical pipe (10). A horizontal pipe (12) is fixedly connected to the lower end of the vertical pipe (10). At the end of the horizontal pipe (12) away from the side pipe (11), the horizontal pipe (12) is connected to one end of another flexible tube (13), and the other end of the flexible tube (13) is connected to an arterial cannula (14).

2. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: The lower ends of the first lead screw (2), the second lead screw (3) and the third lead screw (4) are respectively movably connected to three bearings fixedly installed at the rear end of the top of the base plate (1).

3. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: The adjustment knob (9) is a cylindrical structure, and the surface of the adjustment knob (9) is provided with anti-slip vertical grooves.

4. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: The lifting seat (5) is connected to the surface thread of the first lead screw (2) through a threaded groove opened at the front end of one side.

5. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: The first lifting frame (6) is connected to the surface thread of the second lead screw (3) through a threaded groove opened on one side of its rear end.

6. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: The second lifting frame (7) is connected to the surface thread of the third lead screw (4) through a threaded groove opened at the center of its rear end, and a connecting ring is fixedly connected to the front surface of the second lifting frame (7).

7. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: On the side closer to the side tube (11), this end of the horizontal tube (12) slopes downward.

8. The improved constant-pressure perfusion device for isolated frog hearts according to claim 1, characterized in that: The glass tube (19) has graduation lines.

Images