sarcoplasmatic

Sarcoplasmatic is not a standard term in scientific usage. The widely accepted adjective is sarcoplasmic, describing things related to sarcoplasm, the cytoplasm of muscle cells, or to the sarcoplasmic reticulum, a muscle-specific form of the endoplasmic reticulum involved in calcium handling.

Sarcoplasm contains water, ions, enzymes, glycogen granules, myoglobin, and organelles such as mitochondria. It houses the myofibrils responsible for contraction and is the site of many metabolic processes that supply energy for muscle activity.

The sarcoplasmic reticulum (SR) is a network of membranes that stores calcium ions (Ca2+) and releases them into the cytosol in response to electrical signals. This calcium release triggers the interaction of actin and myosin, enabling muscle contraction; calcium is subsequently pumped back into the SR by SERCA pumps to terminate contraction and reset the system for the next cycle.

In practice, most sources prefer sarcoplasmic. The form sarcoplasmatic may appear as a misspelling or variant, and, when encountered, should be normalized to sarcoplasmic for consistency in terminology.