To begin, divide a two-meter long rope into six equal segments. Use the spring-loaded buckle mechanism to fasten the ends of the ropes, allowing for easy adjustment of loop sizes. Thread each of the six ropes through the designated holes in the fixator.
Next position the rodent's head within the U-shaped hole in the fixator. Carefully fasten the loops around the rodent's neck and gently guide its body through two of the prepared rope loops. Then fasten the loops around the rodent's abdomen, ensuring it is tight enough without causing respiratory distress.
Similarly immobilize the other two rodents. Find the acupoints by anatomical location and confirm the insertion depth at the acupoint. Slowly twist and insert the disposable sterile needles bilaterally and subcutaneously into MS6 or the ST25.
Next, connect one side of the connection cable to the electroacupuncture instrument. Connect the other side of the connection cable with the positive and negative clips to the acupuncture needle shanks on the left and right MS6. Turn on the electroacupuncture instrument.
Rotate the function or choose switch button to set the frequency and function mode. Set the frequency to 10 Hertz and choose a continuous wave mode. Rotate the Adjust Intensity button to set the intensity at one to two milliamperes lasting for five minutes.
The 3D-printed fixator allowed for the simultaneous firm immobilization of three mice in both supine and prone positions without injury. The MS6 and ST25 acupoints were successfully located and needled in rodents. The average time for immobilization of three rats in both positions was between 72 to 77 seconds.