apocrine gland

Any exocrine gland whose cells bud their secretions off through the plasma membrane producing membrane-bound vesicles in the lumen; the apical portion of the secretory cell of the gland pinches off and enters the lumen; it loses part of its cytoplasm in their secretions; apocrine secretion is functional during hormonal stress or puberty; an example of true apocrine glands are mammary glands, responsible for secreting breast milk.