How to set up the Millar MPVS Ultra for small animal research

Our step-by-step guide to connecting the Millar MPVS Ultra with a C Series Instrument Interface and LabChart.

Overview:

Our Head of Support, Mark de Reus, demonstrates how to connect the Millar Mikro-Tip® Pressure Volume System (MPVS) Ultra with a C Series Instrument Interface to measure small animal PV in LabChart.

Equipment Required:
Hardware Set-Up:
  1. Connect the MPVS Ultra to the computer using the supplied USB cable.   
  2. Connect the C Series Instrument Interface to the computer using the supplied interface cable.   
  3. Connect the power cable to the MPVS Ultra and switch on the unit.   
  4. Connect the PV Interface cable to the front of the MPVS Ultra:   
    1. For a single PV input, the interface cable should be attached to the black input slot.   
    2. When using a second pressure catheter, or a dual pressure catheter, connect the second interface cable to the blue input slot.   
  5. Using a BNC cable, connect the ‘CH1’ pressure output on the MPVS Ultra to the first input slot on the C Series Instrument Interface.   
  6. Using a BNC cable, connect the ‘S1’ volume output on the MPVS Ultra to the second input slot on the C Series Instrument Interface.   
  7. Connect the PV Catheter to the interface cable.   
    1. It is recommended that you do this while the catheter is still in its protective anti-static pink foam.   
  8. Soak the catheter in 37℃ saline for at least half an hour before implanting.
Software Set-Up:
  1. Launch the LabChart software.   
  2. Launch the MPVS Ultra control software.   
  3. In the MPVS Ultra control software:   
    1. Select your catheter:   
      1. Click on the orange ‘Catheter Configuration Locked’ button.   
      2. Select the correct catheter in the ‘Millar Catheter Selection’ list.   
      3. Click on the green ‘Catheter Configuration Unlocked’ button.   
    2. Zero your catheter:   
      1. Select the ‘Catheter Calibration’ tab.   
      2. Click on the orange ‘Balance Locked’ button.   
      3. Ensure the catheter sensor is just below the saline surface.   
      4. Click the ‘auto zero’ button for ‘pressure 1’.   
  4. In LabChart:   
    1. Select the PV Loop dropdown menu and click on ‘workflow’. This will open the workflow window on the left of the screen.   
    2. Select ‘small mammal’ from the ‘Select Workflow’ dropdown menu.   
    3. In the ‘Pressure Channel’ dropdown list, select the channel connected to the MPVS pressure output. If you’re following the above instructions, this will be Channel 1.   
    4. In the ‘Volume Channel’ dropdown list, select the channel connected to the MPVS volume output. If you’re following the above instructions, this will be Channel 2.   
  5. Pressure Calibration:   
    1. Select ‘Pressure Calibration’.   
    2. Click on ‘Start sampling’.   
    3. Open the MPVS Ultra control software.   
      1. In the ‘Pressure’ column of the ‘Catheter Calibration’ tab, press the ‘25 mmHg’ button.   
      2. After a couple of seconds click on the ‘100 mmHg’ button.   
      3. After a couple of seconds click the ‘Transducer’ button.   
    4. Return to LabChart.   
      1. Stop the recording.   
      2. In channel 1, select the part of the data which corresponds to the 25mmHg step.   
      3. Click on the first arrow in the ‘Pressure Calibration’ section of the ‘PV Loop Workflow’ window on the left of the screen. This will place the voltage value in the corresponding box.   
      4. Type ‘25’ into the box to the right, indicating that the voltage recorded is related to 25mmHg.   
      5. Repeat this process for the 100mmHg step in the boxes on the next line.   
      6. Check the ‘Apply pressure calibration’ box.   
  6. Conductance Calibration:   
    1. Select ‘Conductance Calibration’.   
    2. Click on ‘Start sampling’.   
    3. Open the MPVS Ultra control software.   
      1. In the ‘Volume’ column of the ‘Catheter Calibration’ tab, press the blue ‘Show Conductance Display’ button.   
      2. Click the ‘1.14 mS’ button.   
      3. After a couple of seconds click the ‘2.78 mS’ button.   
      4. After a couple of seconds click the ‘Transducer’ button.   
    4. Return to LabChart.   
      1. Stop the recording.   
      2. In channel 2, select the part of the data which corresponds to the 1.14mS step.   
      3. Click on the first arrow in the ‘Conductance calibration’ section of the ‘PV Loop Workflow’ window on the left of the screen. This will place the voltage value in the corresponding box.   
      4. Type ‘1.14’ into the box to the right, indicating that the voltage recorded is related to 1.14mS.   
      5. Repeat this process for the 2.78mS step in the boxes on the next line.   
      6. Check the ‘Apply conductance calibration’ box.
Further Information: