PARIETAL CELLS Meaning and
Definition
-
Parietal cells are specialized cells found in the lining of the stomach, primarily in the gastric glands of the stomach's fundus and body regions. They play a crucial role in the production of gastric acid, also known as hydrochloric acid (HCl). These cells are responsible for secreting HCl into the stomach to aid in the digestion and breakdown of food.
Parietal cells are unique as they contain numerous mitochondria and secretory canaliculi, which are invaginations in the cell membrane that increase the surface area for acid secretion. These characteristics allow for their efficient production and release of gastric acid.
The secretion of HCl by parietal cells serves several key functions within the stomach. It helps maintain the stomach's acidic pH level, which is essential for activating various digestive enzymes, such as pepsin, and facilitating the breakdown of proteins into smaller molecules. Furthermore, gastric acid also kills many harmful bacteria and pathogens that may enter the stomach through food, thus aiding in the body's defense against infections.
Disorders or imbalances in the function of parietal cells can lead to various gastric conditions. For instance, excessive acid production can cause conditions like gastric ulcers and gastroesophageal reflux disease (GERD), while decreased acid production can result in conditions like hypochlorhydria or achlorhydria. Medications known as proton pump inhibitors (PPIs) can be used to reduce gastric acid secretion by targeting the function of parietal cells.
Etymology of PARIETAL CELLS
The word "parietal" in "parietal cells" has its etymology rooted in Latin. It comes from the Latin word "parietalis", which means "relating to a wall" or "belonging to a wall". In the context of "parietal cells", these are particular cells found within the lining (or wall) of the stomach. These cells are responsible for producing gastric acid.
