oxyntic

Oxynctic, in anatomical and histological contexts, refers to the acid-secreting portion of the stomach, specifically the glands located in the fundus and body. The term derives from Greek roots associated with sharp or acid, and it is used to distinguish the acid-producing mucosa from other parts of the stomach such as the pyloric region.

The oxyntic mucosa contains oxyntic glands, which house the parietal (oxyntic) cells responsible for secreting hydrochloric acid and intrinsic factor, as well as chief cells that produce pepsinogen and mucous neck cells. This region also includes various neuroendocrine cell types. Acid secretion is regulated by histamine from enterochromaffin-like cells, acetylcholine from vagal nerves, and gastrin from G cells, collectively lowering stomach pH and aiding digestion; intrinsic factor is essential for vitamin B12 absorption.

In modern anatomy and physiology, the term oxyntic is somewhat superseded by more specific terminology: the cells are commonly called parietal cells, and the mucosa is described as the fundic or oxyntic mucosa. Nevertheless, the phrase remains encountered in older literature and in comparative anatomy to describe acid-secreting gastric tissue or glands.

Clinical relevance is often linked to changes in the oxyntic mucosa. Autoimmune gastritis can target parietal cells, leading to hypochlorhydria or achlorhydria and loss of intrinsic factor, with pernicious anemia as a potential consequence. Loss or alteration of oxyntic tissue can also be observed in various gastric diseases, including certain metaplastic or inflammatory conditions.