part of part of epithelial cell epidermal cell epithelial cell of skin gland epithelial cell of sweat gland An epithelial cell that is part of the sweat gland. FMA:70952 https://cellxgene.cziscience.com/cellguide/CL_1000448 Epithelial cells of sweat glands, also known as sudoriferous glandular cells, play a crucial role in the body's thermoregulation, waste excretion, and hydration balance. They form the main structure of the sweat glands, which are effectively long, coiled tubes located in the dermis. There are two types of sweat glands – eccrine glands, which typically open directly onto the skin surface (e.g. on palms and soles), and apocrine glands, which open onto associated hair follicles (e.g. in arm pits). Eccrine glands consist of a tube-shaped duct that ends in a coiled, secretory unit made up of three types of epithelial cells – dark, clear and myoepithelial. The dark cells contain basophilic granules to secrete sialomucin, while clear cells secrete glycogen-containing aqueous material; the myoepithelial cells contract in response to stimuli to assist with secretion. Apocrine glands have a similar structure, but their secretory component is larger. The primary function of the epithelial cells of these glands is to produce sweat, a bodily fluid made mostly of water, but also containing trace amounts of salts, glucose, urea, and other substances. This process begins with the secretion of a primary sweat fluid - an isotonic solution derived from the blood plasma - into the glandular lumen. Subsequently, as this primary sweat passes through the gland's duct, reabsorption of sodium ions occurs, leading to a hypotonic final sweat that is excreted onto the skin's surface. This sweat evaporates, removing heat from the body and thus, cooling it down. In addition, epithelial cells of sweat glands contribute to the body's immune defense system. As part of the innate skin barrier function, they secrete antimicrobial peptides and proteins, such as dermcidin, which can inhibit the growth of harmful microorganisms on the skin surface. They also aid in maintaining skin pH and contribute to fluid balance by regulating water resorption. Consequently, any dysfunction in these cells can lead to conditions like hyperhidrosis, anhidrosis, and certain skin infections. Thus, these epithelial cells of sweat glands play a multifaceted role in health and disease. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) sweat gland