Specimen of stomach
This specimen shows the Stomach and its musculature.
Stomach: The stomach is located in the upper left part of the abdominal cavity. It is the widest part of the gastrointestinal tract and appears to be J-shaped. It is continuous with the Oesophagus above and with the Duodenum in the below. It has two orifices (cardiac orifice and pyloric orifice), two curvatures (greater curvature and lesser curvature) and two surfaces (anterosuperior surface and posteroinferior surface). It is divisible into three parts, namely, the fundus, the body and the pylorus. The interior of the stomach shows numerous temporary mucosal folds known as rugae. Its gastric cells secrete Hydrochloric acid and Pepsinogen. Excessive secretion of Hydrochloric acid leads to gastric ulcers. The wall of the stomach shows muscle coats, namely, the innermost oblique, the middle circular and the outer longitudinal muscles.
The oesophagus is a muscular tube extending from the pharynx to the upper end of the stomach. It passes through the oesophageal opening of the diaphragm and ends at the cardiac end of the stomach. The lower part of oesophagus is a site of portocaval anastomosis.
The greater curvature is the left border of the stomach. It gives attachment to the folds of peritoneum namely, the gastrophrenic ligament, the gastrosplenic ligament and the greater omentum.
The lesser curvature is the right border of the stomach. It gives attachment to the lesser omentum which extends from the porta hepatis to the lesser curvature.
The fundus of the stomach is the uppermost dilated part of the stomach. In the contrast radiograph, the area of the fundus appears dark due to gas present within it.
The interior of the body of the stomach presents numerous temporary mucosal folds known as the rugae.
The pylorus is the terminal part of the stomach. It is further divided into a proximal pyloric antrum and a distal pyloric canal. An anatomical sphincter is present in the pylorus.
Oblique, circular and longitudinal muscle coat:
The wall of the stomach is comprised of smooth muscles arranged obliquely, circularly and longitudinally. They regulate the movement of the stomach.