Apokrintikos

Apokrintikos is a term derived from the Greek word "apokrinetai," meaning to secrete or discharge. In a biological context, it refers to a type of gland that releases its secretions by breaking down and shedding the entire cell. This is in contrast to holocrine glands, which release their contents through cell lysis, and merocrine glands, which secrete through exocytosis.

Apocrine secretion involves the accumulation of secretory products within the cell, often in vesicles. The apical portion of the cell, containing the secretory vesicles and some cytoplasm, then pinches off from the rest of the cell. The detached portion, or "apokrinetikos" product, is then released as the secretion. The remaining part of the cell can then regenerate and repeat the process.

This mode of secretion is observed in certain glands of the body, notably the apocrine sweat glands, which are found primarily in the axillae and groin. These glands produce a thicker, lipid-rich sweat that is associated with body odor. Mammary glands, during lactation, also exhibit apocrine secretion, releasing milk fat in this manner. The sebaceous glands, responsible for producing sebum, are often described as having a mixed mode of secretion, but are primarily considered holocrine. Understanding apocrine secretion is crucial in histology and physiology for comprehending the mechanisms of glandular function and the composition of various bodily secretions.