Stomach

Stomach

Definition

The stomach is the muscular bag it is the widest and most distensible part of alimentary canal.This is the part of the digestive system.

In this article we are discussing  about these topics...

1. Synonym
2. Location
3. Shape
4. Measurement
5. Functions of stomach
6. Presenting part
7. Relations of the stomach
8. Parts of the stomach
9. Gastric triangle
10. Cellular structure
11. Glandular structure
12. Gastric secretions
13. Blood supply
14. Lymphatic drainage
15. Nerve supply
16. Applied anatomy

Synonym

Gaster, Venter, Temporary, reserve wire of food, Widest part of alimentary  canal.

Location

Epigastric region, Umblical region, Left hypochondric region, Left lumbar region.

Shape

Somewhat J shape or sthenic

Hyper sthenic - possibility of duodenal ulcer.

Hypo sthenic - possibility of gastric ulcer.

Measurement

Length of stomach - 25cm

Capacity -

in adult - solid 1kg and liquid 2 liter ( average - 1.5 kg )

in infants - 30 ml average

Functions of stomach

Mixing of food.

Digestion of food.

Secretions ( Pepsin, mucous, hormones, Hcl.

Presenting parts

1. Two curvature ( Lesser and greater curvature ) / borders ( Right and left borders ).

2. Two surfaces ( Antero-superior and postero-inferior)

3. Two orifices ( Cardiac and pyloric orifice ).

External features of the stomach

Relations

Anterior surface -

Liver, diaphragm, transverse colon, anterior abdominal wall.

Posterior surface / stomach bed

Diaphragm, left kidney, left supra-renal gland, pancreas, transverse mesocolon, left colic flexure and splenic artery ( some time spleen ).

The stomach bed

Superiorly

Oesophagus and diaphragm.

Inferiorly  

Transverse colon and small intestine.

On both side

Crush of diaphragm.

Parts of stomach

1. Cardiac orifice

2. Fundus

3, Body ( 72-80 % part of the stomach )

4. Pylorus

Gastric triangle

Right - Liver

Left - Borders of ribs.

Lower / Inferior  - Transverse colon

Cellular structure

Inner to outer...

1. Mucous coat

2. Sub mucous coat

3. Muscular coat

• Oblique layer (inner)
• Circular layer ( middle )
• Longitudinal layer (outer )

4. Serosa

Anterior view of regions of the stomach

Three-dimensional view of layers of the stomach

Glandular structure

Cardiac glands

Fundic glands

Pyloric glands

Types of cell and glands of the stomach

Gastric secretions

1. Mucous - these cell present on cardiac end as well as pyloric end.

2. HCL ( hydrochloric acid ) - it secret from parietal cells.

3. Enzymes - 

• Proteolytic enzymes - Pepsin, Renin
• Amylolytic enzymes - Gastric amylase
• Lipolytic enzymes - Gastric lipase
• Other enzymes - Intrinsic factor

4. Hormones - Gastrin, Somatostatin, Enkephalins,   

Blood supply

Arterial supply

Right and left gastric arteries.

Right and left gastrosplenic arteries.

Short gastric arteries (5-7).

Venous drainage

Portal vein.

Superior mesenteric vein

Splenic vein

Lymphatic drainage

Pancreaticosplenic lymph node.

Left gastric lymph node.

Right gastroepiploic lymph node.

Nerve supply

Sympathetic - T6 - T10 

Parasympathetic - Vagus nerve.

Applied

1. Peptic ulcer.
2. Gastric ulcer.
3. Gastritis.
4. Dysphagia.
5. Dyspepsia.
6. Pyloric stenosis.
7. Gastrectomy.
8. Gastroenterostomy.
9. Pyloric spasm.
10. Vagotomy.

images of this article are copied from BD Chourasia and Tortora books.