Contents
IX
Composition of Pancreatic Juice
202
Large Intestine
202
12.2
Gastrointestinal Hormones
202
Gastrin
203
Peptic Ulcer Disease
207
Cholecystokinin
208
Secretin
208
Gastric Inhibitory Peptide
208
12.3
Digestion and Absorption of Major Food
Substances
208
Carbohydrates
208
Digestion of Starch
209
Brush-Border Surface Hydrolysis
211
Transport of Monosaccharides into
the Enterocyte
211
Na+,K+ -ATPase
212
Disorders of Carbohydrate Digestion
and Absorption
212
Proteins
214
Digestion
214
Absorption of Amino Acids and Oligopeptides
215
Disorders of Protein Digestion and Absorption
216
Lipids
216
Intraluminal Phase
216
Intracellular (Mucosal) Phase
218
Secretion
218
Disorders of Lipid Digestion and Absorption
218
General Malabsorptive Problems
218
12.4
Absorption of Water and Electrolytes
222
Disorders of Fluid and Electrolyte
Absorption
222
12.5
Thermic Effect of Food
224
Supplemental Readings
and References
224
CHAPTER
13
Carbohydrate Metabolism I: Glycolysis
and TCA Cycle
13.1
Glycolysis
225
Source and Entry of Glucose into Cells
225
Reactions of Glycolysis
226
Phosphorylation of Glucose
226
Isomerization of Glucose-6-Phosphate to
Fructose-6-Phosphate
229
Phosphorylation of Fructose-6-Phosphate to
Fructose-1,6-Bisphosphate
229
Cleavage of Fructose-1,6-Bisphosphate into Two
Triose Phosphates
229
Isomerization of Dihydroxyacetone Phosphate to
Glyceraldehyde 3-Phosphate
229
Dehydrogenation of Glyceraldehyde
3-Phosphate
230
Phosphorylation of ADP from
1,3-Bisphosphoglycerate
231
Isomerization of 3-Phosphoglycerate to
2-Phosphoglycerate
231
Dehydration of 2-Phosphoglycerate to
Phosphoenolpyruvate
232
Phosphorylation of ADP from
Phosphoenolpyruvate
232
Reduction of Pyruvate to Lactate
233
Alternative Substrates of Glycolysis
234
Role of Anaerobic Glycolysis in Various Tissues
and Cells
235
Glycolytic Enzyme Debciencies
in Erythrocytes
235
13.2
Pyruvate Metabolism
235
Lactic Acidemia and Lactic Acidosis
236
D-Lactic Acidosis
236
Oxidation of Pyruvate to Acetyl-CoA
236
Regulation of Pyruvate Dehydrogenase Activity
239
Abnormalities of Pyruvate Dehydrogenase
Complex
240
13.3
Tricarboxylic Acid (TCA) Cycle
241
Reactions of TCA Cycle
241
Condensation of Acetyl-CoA with Oxaloacetate to
Form Citrate
241
Isomerization of Citrate to Isocitrate
241
Oxidative Decarboxylation of Isocitrate to
a-Ketoglutarate
243
Oxidative Decarboxylation of a-Ketoglutarate to
Succinyl-CoA
243
Conversion of Succinyl-CoA to Succinate Coupled to
Formation of GTP
243
Dehydrogenation of Succinate to Fumarate
244
