Covers the histology of the stomach's two mucosal regions, starting with the fundus and body (oxyntic mucosa) and then the pylorus (antral mucosa). For each region it sets out the gland structure, pit-to-gland ratios, and the cell types with their secretory products and appearance, including parietal, chief, mucous and the endocrine cells such as D, ECL, X, G and EC cells. It closes with turnover rates and protective mechanisms of the mucosa.
Topic 12 of 17 in the MU Sofia syllabus for Histology (Medicine, Year 2). The free AceMed note covers it in 3 sections, about 382 words (3 min of reading), with 22 flashcards.
In this note
Introduction
Fundus Histology (Oxyntic Mucosa)
Pylorus Histology (Antral Mucosa)
Fundus Histology (Oxyntic Mucosa)
Anatomic Region:
Location: Body (corpus) and fundus of the stomach.
Glandular Structure:
Glands: Tightly packed acid and enzyme-secreting glands.
Ratio of Pit to Gland Volume: 25:75.
Glandular Constituents: Predominantly parietal cells and chief cells.
Interspersed Mucin Cells: Especially present in the glandular isthmus/neck.
Cell Types and Functions:
Parietal Cells:
Function: Produce hydrochloric acid via H+/K+-ATPase pump, maintain gastric acidity (pH 1.5 to 3.5).
Products: Hydrochloric acid, intrinsic factor.
Location: Predominantly occupy the superficial half of body/fundic glands.
Appearance: Relatively large, triangular cells with eosinophilic cytoplasm and centrally placed nuclei.
Chief Cells:
Function: Produce pepsinogen I and II, which are activated to pepsin in an acidic environment.
Location: Predominantly occupy the basal half of corpus glands.
Appearance: Cuboidal cells with basophilic to amphophilic cytoplasm.
Endocrine Cells:
Types and Functions:
D Cells: Produce somatostatin; distributed throughout the whole stomach.
Enterochromaffin-like (ECL) Cells: Produce histamine; limited to the gastric body and fundus.
X Cells: Produce grehlin; limited to the gastric body and fundus, concentrated in mucous neck region.
Distribution: Scattered throughout oxyntic glands with a majority of ECL cells.
General Characteristics:
Metabolic Activity: Gastric mucosa is highly active with regular turnover of surface epithelium every 4-8 days and slower turnover for parietal and chief cells (1-3 years).
