An intradermal injection is administered into the dermis, the layer just beneath the epidermis, using a small-gauge needle at a shallow angle (10–15°).

Hepatic portal vein (HPV) injection is a method used to deliver substances directly into the liver via the portal circulation.

Intraperitoneal (IP) injection is a method for administering drugs, vaccines, or biological agents into the peritoneal cavity.

Subcutaneous (SC) injection is a technique for delivering drugs, vaccines, or biological agents into the subcutaneous tissue.

Intravitreal injection is a technique used to deliver drugs, viral vectors, or cells directly into the vitreous humor of the eye.

The calcium imaging protocol involves loading neurons with a fluorescent calcium indicator, stimulating neuronal activity, and capturing calcium transients using fluorescence microscopy