Caliciform cells are intraepithelial cells scattered in the covering epithelium of the intestine (small and large intestine), and larger respiratory ducts (trachea and bronchi). Caliciform cells resemble a calyx, with the apical part wider than the basal one. The nucleus is located in the basal part and the secretory vesicles are located toward the apical part (stained in red in this image). The release of the secretory products is by merocrine secretion, after a cholinergic stimulus from the autonomous system. After every secretion event, caliciform cell becomes thinner and starts to synthesize new molecules to be released in the next secretion event. The time between two releases is around 1 or 2 hours.