smakcellerna

Smakcellerna, or taste cells, are specialized sensory epithelial cells that form the sensory elements of the gustatory system. They reside within taste buds, clusters scattered on the tongue’s surface as well as in the soft palate and other parts of the oral cavity. Each taste bud contains mature taste receptor cells together with supporting and basal progenitor cells. The microvilli of the taste cells extend into a taste pore, where they come into contact with tastants dissolved in saliva.

Taste receptor cells are organized into several functional types. Type II receptor cells detect sweet, umami, and bitter compounds through G-protein-coupled receptors (GPCRs); contemporary classifications assign T1R receptors to sweet (T1R2+T1R3) and umami (T1R1+T1R3) sensing, while a family of T2R receptors detects bitter tastes. Type III cells are associated with sour taste and provide conventional synaptic transmission to gustatory nerve fibers, contributing to the response to acids. Salt detection is mediated by ion channels in distinct taste cells. In addition, Type II cells release ATP as a neurotransmitter to activate nearby gustatory neurons via CALHM channels, representing a key signaling mechanism in taste perception. Supportive Type I cells play a glia-like role.

Taste buds are innervated by cranial nerves VII, IX, and X, transmitting signals to the brain where taste is integrated with smell, texture, and temperature. Taste cells are rapidly renewed, with turnover on the order of one to two weeks from basal progenitors, making the system dynamic and adaptable. Age, medications, and smoking can influence taste perception in humans. Smakcellerna thus form a compact, evolving interface between chemical stimuli and neural signaling.