This article describes the procedure for performing intraperitoneal injections in mice, specifically for the administration of ovarian cancer cells. It emphasizes the importance of proper restraint and technique to avoid injury to the abdominal organs during the injection process.
The peritoneal cavity is the space between the abdominal wall and the lining of the internal organs. For intraperitoneal injection, begin by restraining a live mouse by its neck region such that the mouse’s head tilts downward with its ventral abdomen exposed.
Restraining the mouse restricts its movement and shifts the abdominal organs towards the diaphragm, preventing accidental damage to the organs during needle insertion.
Adjacent to the midline across the mouse’s abdomen, in the lower right quadrant, locate a point for needle insertion. This site prevents the risk of puncturing the caecum.
Next, take a syringe containing a single cell suspension of ovarian cancer cells. Insert the needle at the chosen point to a depth of approximately half a centimeter to penetrate just the outer abdominal wall. Finally, inject the cancer cell suspension slowly. This ensures efficient distribution of cells within the peritoneal cavity.
Return the mouse to its cage and monitor it for tumor growth. The tissues within the peritoneal cavity may release specific chemotactic molecules that attract the cancer cells leading to their migration and colonization, eventually contributing to tumor development.
Load 500 microliters of the fluorescently tagged single cell suspension into the syringe. Then, put the syringe into a sterile capped 25 gauge needle to reduce cell shearing prior to injection. Restraining the mouse with the other hand, pick the mouse up by the scruff of the neck and hold the tail using the palm and forefinger. Then, fix the left hind leg between the ring and little finger. To avoid traumatizing abdominal organs, restrain the mouse well so that it cannot move during the injection.
Imagine a line across the abdomen, and locate a point on the animal's right side and close to the midline. The point of entry is cranial to and slightly medial of the last nipple. Prepare to insert the needle on the mouse's right side to avoid the cecum and reduce the risk of puncturing the intestines. Insert the needle at the lower lateral region of the mouse's abdomen to a depth of approximately 0.5 centimeters. Pull back on the plunger to confirm that the needle has not penetrated a blood vessel or other peritoneal organs.
If no fluid is aspirated, inject the sample using slow steady pressure. Then, withdraw the needle and return the mouse to its cage. Do not recap syringe before disposal in the sharps container.
繁體中文
