Apocrine metaplasia is a reversible transformation of cells to an apocrine phenotype. The stratified squamous epithelium gradually accumulates sebaceous and apocrine glands. Two types of sweat glands can be found in humans&colon; eccrine glands and apocrine glands. Apocrine sweat glands secrete sweat into the pubic hair follicles. They are larger than eccrine glands, but smaller than apocrine glands. Sebaceous and apocrine glands become active at puberty. Mammary glands use apocrine secretion to produce milk. The sacs are lined with apocrine and sebaceous glands. Sebaceous secretions in conjunction with apocrine glands also play an important thermoregulatory role. They regulate sebaceous glands, apocrine hair growth, and libido. Axillary steroids are produced by the testes, ovaries, apocrine glands and adrenal glands. Axillary steroids are produced by the testes, ovaries, apocrine glands, and adrenal glands. The mammary gland is thought to have derived from apocrine skin glands. An example of true apocrine glands is the mammary glands, responsible for secreting breast milk. In mink, symptoms include increased secretion from apocrine glands.