acineuses

Acineuses is a term used in French histology (feminine plural) that designates tissues composed of acini, the secretory units of many exocrine glands. In English-language literature the corresponding terms are acinar or acinous, and the units are called acini. The term emphasizes a glandular organization in which cells cluster around a lumen.

An acinus consists of secretory cells arranged around a small duct or lumen, typically forming a spherical or grape-like unit. The cells are often arranged in one layer and may be serous, mucous, or mixed. Acini drain through intralobular ducts into larger ducts that carry secretions to the gland’s excretory system. The lumen usually opens into a network of ducts that connect the acini to the main duct system.

Exocrine glands with acinar units include the pancreas, where serous acini secrete digestive enzymes into ducts, and the parotid and other salivary glands, where acini produce enzymatic and mucous secretions of varying composition. In some glands the secretory units are described as alveolar or acinar-like, particularly in mammary tissue, where secretory units resemble small sacs within the gland.

Pathology and clinical relevance: acinar cell carcinoma is a malignant pancreatic tumor characterized by acinar differentiation and enzyme production. Acinar architecture can also be altered by atrophy, hypertrophy, or dysplasia in various diseases, reflecting changes in exocrine secretory units.