Comprehensive Physiology Wiley Online Library

The Gastrointestinal Tract

Full Article on Wiley Online Library


The sections in this article are:

1 Salivary Glands
2 Stomach
2.1 Gastric Secretion
3 Small Intestine
3.1 Morphology
3.2 Brush Border Membranes
3.3 Enzymes
3.4 Intestinal Permeability
3.5 Protein Synthesis
3.6 Intestinal Absorption
4 Gut‐Associated Immune System
5 Splanchnic Blood Flow
6 Gastrointestinal Motility
6.1 Esophagus
6.2 Stomach
6.3 Neuromuscular Functioning
6.4 Colon and Rectum
7 Pancreas
8 Liver and Biliary Tree
8.1 Morphology
8.2 Age‐Associated Effects
8.3 Consequences of Aging
8.4 Bile
9 Gastrointestinal Hormones
10 Cellular Proliferation
10.1 Esophagus and Stomach
10.2 Small Intestine
10.3 Colon
10.4 Effects of Caloric Restriction
Figure 1. Figure 1.

Effect of calcium diet in young and old subjects. Each subject was studied twice, once on the low‐calcium diet and once on the high‐calcium diet. P values are by paired analysis.

Reprinted from Ireland and Fortran 214 with permission
Figure 2. Figure 2.

Relation between age and hepatic secretion of cholesterol (n = 22), total bile acid synthesis (n = 18), and size of cholic acid pool (n = 18). Open circles denote women and closed circles men. To convert values for bile acids and cholesterol to milligrams, multiply by 400 and 0.39, respectively.

Reprinted from Einarsson et al. 115 with permission

Figure 1.

Effect of calcium diet in young and old subjects. Each subject was studied twice, once on the low‐calcium diet and once on the high‐calcium diet. P values are by paired analysis.

Reprinted from Ireland and Fortran 214 with permission

Figure 2.

Relation between age and hepatic secretion of cholesterol (n = 22), total bile acid synthesis (n = 18), and size of cholic acid pool (n = 18). Open circles denote women and closed circles men. To convert values for bile acids and cholesterol to milligrams, multiply by 400 and 0.39, respectively.

Reprinted from Einarsson et al. 115 with permission
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Peter R. Holt. The Gastrointestinal Tract. Compr Physiol 2011, Supplement 28: Handbook of Physiology, Aging: 505-554. First published in print 1995. doi: 10.1002/cphy.cp110120