exocrine cell parietal cell oxyntic cell BTO:0001780 Parietal cells have dynamic, actin-supported microvilli that increase in number during active secretion, playing a crucial role in secreting hydrochloric acid and intrinsic factor. The structure and regulation of these microvilli are influenced by proteins such as ASAP3, which modulates Arf6 activity and actin assembly, thereby controlling microvilli formation and parietal cell function. gastric parietal cell FMA:62901 An epithelial cell of the stomach that is part of the fundic gastric gland. This cell is characterized by its pyramidal shape, abundant mitochondria, and a complex network of secretory canaliculi lined with microvilli. It secretes hydrochloric acid into the stomach lumen and produces intrinsic factor, essential for vitamin B12 absorption. glandular epithelial cell of stomach