腺体的分泌依据其所含的细胞产物或之腺体细胞部份来分类。腺体细胞由细胞膜释放出液体状细胞产物且不丧失细胞质，此种叫做局泌腺(merocrine gland)。有一种中间型即在分泌时会失去腺体细胞细胞质的一小部份，此种称为顶泌腺(apocrine gland)。

腺体发布含分泌产物并崩毁整个细胞，此种称为全泌腺(holocrine gland)，发布充满分泌物的整个细胞，例如皮肤的皮脂腺。

Holocrine is a term used to classify the mode of secretion in exocrine glands in the study of histology. Holocrine secretions are produced in the cytoplasm of the cell and released by the rupture of the plasma membrane, which destroys the cell and results in the secretion of the product into the lumen.