E-Book, Englisch, 786 Seiten
ISBN: 978-0-12-391910-6
Verlag: Elsevier Textbooks
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)
Provides newly developed case studies that demonstrate practical application of conceptsPresents comprehensive sectional exams for self-assessmentDelivers instructor website with updated PowerPoint images and lecture slides to enhance teaching and learningEmploys a succinct communication style in support of quick comprehension
Larry Engelking holds B.S. and M.S. degrees in biology from Idaho State University, and a Ph.D. degree in physiology from Kansas State University. He has held post-doctoral research positions at the University of Florida Veterinary School and the University of Alabama Medical School, teaching positions at Harvard University, and professorial positions at Tufts University. With over 35 years of teaching and research experience, Dr. Engelking is an expert in the fields of biochemistry and physiology.
Autoren/Hrsg.
Weitere Infos & Material
1;Front Cover;1
2;Textbook of Veterinary Physiological Chemistry;2
3;Copyright;3
4;Table of Contents;4
5;Acknowledgments;8
6;Preface to the First Edition;10
7;Preface to the Second Edition;11
8;Preface to the Third Edition;12
9;Section I: Amino Acid and Protein Metabolism;14
9.1;Chapter 1: Chemical Composition of Living Cells;15
9.1.1;Overview;15
9.1.2;Nucleic Acids;16
9.1.3;Proteins;17
9.1.4;Polysaccharides;18
9.1.5;Lipids;18
9.1.6;Objectives ;19
9.2;Chapter 2: Properties of Amino Acids;20
9.2.1;Overview;20
9.2.2;Hydrophilic Amino Acids;22
9.2.3;Hydrophobic Amino Acids;22
9.2.4;Neither Hydrophobic nor Hydrophilic;23
9.2.5;Enantiomers;23
9.2.6;Objectives ;23
9.3;Chapter 3: Amino Acid Modifications;25
9.3.1;Overview;25
9.3.2;Modified Amino Acids Found in Protein;25
9.3.3;Nonprotein Amino Acids;28
9.3.4;Essential and Nonessential Amino Acids;28
9.3.5;Objectives ;29
9.4;Chapter 4: Protein Structure;31
9.4.1;Overview;31
9.4.2;Primary Structure;32
9.4.3;Secondary Structure;33
9.4.4;Tertiary Structure;34
9.4.5;Quaternary Structure;35
9.4.6;Protein Misfolding;35
9.4.7;Protein Denaturation;36
9.4.8;Plasma Proteins;36
9.4.9;Objectives ;37
9.5;Chapter 5: Properties of Enzymes;39
9.5.1;Overview;39
9.5.2;General Properties of Enzymes;40
9.5.3;Enzyme Nomenclature;40
9.5.4;Coenzymes;40
9.5.5;Control of Enzyme Activity;40
9.5.6;Objectives ;43
9.6;Chapter 6: Enzyme Kinetics;45
9.6.1;Overview;45
9.6.2;Substrate Saturation Curves;46
9.6.3;Double Reciprocal Plots;47
9.6.4;Enzyme Inhibitors;47
9.6.5;Reversible, Competitive Inhibitors;47
9.6.6;Reversible, Noncompetitive Inhibitors;48
9.6.7;Uncompetitive Inhibitors;48
9.6.8;Irreversible Inhibitors;48
9.6.9;Therapeutic Inhibitors;48
9.6.10;Isozymes;48
9.6.11;Cofactors and Coenzymes;50
9.6.12;Objectives ;50
9.7;Chapter 7: Protein Digestion;52
9.7.1;Overview;52
9.7.2;Tissue Protein Turnover;52
9.7.3;Gastrointestinal Protein Digestion;53
9.7.4;Objectives ;56
9.8;Chapter 8: Amino Acid Catabolism;58
9.8.1;Overview;58
9.8.2;Hepatic Metabolism of Phenylalanine;58
9.8.3;The BCAA/AAA Ratio;59
9.8.4;Intestine;61
9.8.5;Skeletal Muscle;61
9.8.6;Kidney;61
9.8.7;Liver;62
9.8.8;Nitrogen Balance;62
9.8.9;Objectives ;63
9.9;Chapter 9: Transamination and Deamination Reactions;65
9.9.1;Overview;65
9.9.2;Deamination Reactions;66
9.9.3;Transamination Reactions;68
9.9.4;Other Transaminases;69
9.9.5;Objectives ;69
9.10;Chapter 10: Urea Cycle (Krebs-Henseleit Ornithine Cycle);71
9.10.1;Overview;71
9.10.2;Carbamoyl Phosphate Formation;72
9.10.3;Citrulline Formation;72
9.10.4;Argininosuccinate Formation;74
9.10.5;Arginine and Fumarate Formation;74
9.10.6;Urea Formation;74
9.10.7;Abnormalities in Urea Biosynthesis;75
9.10.8;Objectives ;76
9.11;Chapter 11: Glutamine and Ammonia;78
9.11.1;Overview;78
9.11.2;Ammonia Toxicity;78
9.11.3;Nitrogen and Carbon Flux Between Liver and Kidney;78
9.11.4;Objectives ;82
9.12;Chapter 12: Nonprotein Derivatives of Amino Acids;83
9.12.1;Overview;83
9.12.2;Tyrosine (Tyr);83
9.12.3;Tryptophan (Trp);84
9.12.4;Histidine (His);84
9.12.5;Glutamate (Glu);86
9.12.6;Glycine (Gly);86
9.12.7;Arginine (Arg);86
9.12.8;Lysine (Lys);87
9.12.9;Aspartate (Asp);87
9.12.10;Serine (Ser);87
9.12.11;Objectives ;87
10;Addendum to Section I;89
11;Introduction to Section II;89
12;Section II: Nucleotide and Nucleic Acid Metabolism;90
12.1;Chapter 13: Nucleotides;91
12.1.1;Overview;91
12.1.2;Nucleotide Structure;92
12.1.3;Polynucleotide Structure and Synthesis;94
12.1.4;Objectives ;95
12.2;Chapter 14: Pyrimidine Biosynthesis;96
12.2.1;Overview;96
12.2.2;Pathway Summary;96
12.2.3;Pathway Regulation;98
12.2.4;Unusual Physical Properties of Relevant Early Stage Mammalian Enzymes;98
12.2.5;Objectives ;100
12.3;Chapter 15: Purine Biosynthesis;101
12.3.1;Overview;101
12.3.2;Phase One - PRPP Biosynthesis;103
12.3.3;Phase Two - Formation of IMP (the parent NMP);103
12.3.4;Phase Three - Formation of AMP, GMP, and the Respective 5'-triphosphates;103
12.3.5;Formation of NDP and NTP Forms of Adenine and Guanine;104
12.3.6;Regulation of Purine Biosynthesis;104
12.3.7;Objectives ;105
12.4;Chapter 16: Folic Acid;106
12.4.1;Overview;106
12.4.2;Folic Acid and its Active Form, Tetrahydrofolate;106
12.4.3;Folate Metabolism in Animals vs Bacteria;106
12.4.4;THFA-mediated One-carbon Metabolism;108
12.4.5;Folate Plasma Concentrations;108
12.4.6;Megaloblastic Anemia (MA);108
12.4.7;Formation of Deoxyribonucleotides;109
12.4.8;Conversion of dUTP to its 5-methyl Form, dTTP;109
12.4.9;Chemotherapeutic Drug Targets in dNTP and Folate Metabolism;110
12.4.10;Objectives ;110
12.5;Chapter 17: Nucleic Acid and Nucleotide Turnover;111
12.5.1;Overview;111
12.5.2;Release of Bases from Nucleic Acids;111
12.5.3;Nucleotides and Nucleosides;112
12.5.4;Salvage of Purine and Pyrimidine Bases;112
12.5.5;Degradation of Pyrimidine Bases;113
12.5.6;Degradation of Purine Bases;114
12.5.7;Excretion of Purine Degradation Products;116
12.5.8;Uric Acid and Health;116
12.5.9;Objectives ;117
13;Sections I and II Examination Questions;118
14;Addendum to Section II;129
15;Introduction to Section III;129
16;Section III: Carbohydrate and Heme Metabolism;130
16.1;Chapter 18: Carbohydrate Structure;131
16.1.1;Overview;131
16.1.2;Complex Carbohydrates;131
16.1.3;Monosaccharides;132
16.1.4;Pentoses, NAD+ and NADP+, NADH and NADPH;132
16.1.5;Hexoses;133
16.1.6;Disaccharides and Trisaccharides;134
16.1.7;Objectives ;135
16.2;Chapter 19: Polysaccharides and Carbohydrate Derivatives;137
16.2.1;Overview;137
16.2.2;Polysaccharides;137
16.2.3;Carbohydrate Derivatives;139
16.2.4;Objectives ;142
16.3;Chapter 20: Glycoproteins and Glycolipids;143
16.3.1;Overview;143
16.3.2;Glycoproteins;143
16.3.3;Glycolipids;147
16.3.4;Objectives ;148
16.4;Chapter 21: Overview of Carbohydrate Metabolism;149
16.4.1;Overview;149
16.4.2;Objectives ;153
16.5;Chapter 22: Glucose Trapping;154
16.5.1;Overview;154
16.5.2;Objectives ;158
16.6;Chapter 23: Glycogen;160
16.6.1;Overview;160
16.6.2;Glycogenesis;161
16.6.3;Glycogenolysis;162
16.6.4;Glycogen Storage Diseases;164
16.6.5;Objectives ;165
16.7;Chapter 24: Introduction to Glycolysis (The Embden-Meyerhoff Pathway (EMP));166
16.7.1;Overview;166
16.7.2;Why is Anaerobic Glycolysis Necessary?;169
16.7.3;Historical Perspective;170
16.7.4;Objectives ;171
16.8;Chapter 25: Initial Reactions in Anaerobic Glycolysis;172
16.8.1;Overview;172
16.8.2;Objectives ;176
16.9;Chapter 26: Intermediate Reactions in Anaerobic Glycolysis;177
16.9.1;Overview;177
16.9.2;Objectives ;181
16.10;Chapter 27: Metabolic Fates of Pyruvate;182
16.10.1;Overview;182
16.10.2;Objectives;185
16.11;Chapter 28: Hexose Monophosphate Shunt (HMS);187
16.11.1;Overview;187
16.11.2;Objectives ;190
16.12;Chapter 29: Uronic Acid Pathway;192
16.12.1;Overview;192
16.12.2;Objectives ;196
16.13;Chapter 30: Erythrocytic Protection from O2 Toxicity;197
16.13.1;Overview;197
16.13.2;Oxygen Toxicity;197
16.13.3;Cellular Protection Against Free Radicals;198
16.13.4;Objectives ;201
16.14;Chapter 31: Carbohydrate Metabolism in Erythrocytes;203
16.14.1;Overview;203
16.14.2;Objectives ;206
16.15;Chapter 32: Heme Biosynthesis;208
16.15.1;Overview;208
16.15.2;Harderian Glands;211
16.15.3;Photodynamic Therapy (PDT);211
16.15.4;Hemoglobin (Hb);211
16.15.5;Anemias and Polycythemia;213
16.15.6;Objectives ;213
16.16;Chapter 33: Heme Degradation;215
16.16.1;Overview;215
16.16.2;Hepatic Bilirubin Uptake, Conjugation, and Excretion;217
16.16.3;Characterization of Plasma Bilirubin;218
16.16.4;Objectives ;220
16.17;Chapter 34: Tricarboxylic Acid (TCA) Cycle;221
16.17.1;Overview;221
16.17.2;Exchange Transporters of the Inner Mitochondrial Membrane;225
16.17.3;Objectives ;226
16.18;Chapter 35: Leaks in the Tricarboxylic Acid (TCA) Cycle;227
16.18.1;Overview;227
16.18.2;TCA Cycle Intermediates are Converted to Other Essential Compounds;227
16.18.3;Replenishment of TCA Cycle Intermediates;229
16.18.4;Objectives ;231
16.19;Chapter 36: Oxidative Phosphorylation;232
16.19.1;Overview;232
16.19.2;Movement of Electrons from Cytoplasmic NADH to the Mitochondrial ETC;232
16.19.3;Oxidation and Reduction;234
16.19.4;Phosphorylation;234
16.19.5;Inhibitors and Uncouplers;236
16.19.6;Objectives ;236
16.20;Chapter 37: Gluconeogenesis;238
16.20.1;Overview;238
16.20.2;Gluconeogenic Precursors;240
16.20.3;Gluconeogenic Enzymes;241
16.20.4;Objectives ;243
16.21;Chapter 38: Carbohydrate Digestion;244
16.21.1;Overview;244
16.21.2;Salivary .-Amylase (Ptyalin);244
16.21.3;Intestinal Carbohydrate Digestion;245
16.21.4;Intestinal Monosaccharide Absorption;247
16.21.5;Objectives ;249
17;Section III Examination Questions;251
18;Addendum to Section III;265
19;Introduction to Section IV;265
20;Section IV: Vitamins and Trace Elements;266
20.1;Chapter 39: Vitamin C;267
20.1.1;Overview;267
20.1.2;Water-soluble Vitamins;267
20.1.3;Objectives ;272
20.2;Chapter 40: Thiamin (B1) and Riboflavin (B2);273
20.2.1;Overview;273
20.2.2;Thiamin (Vitamin B1);273
20.2.3;Riboflavin (Vitamin B2);275
20.2.4;Objectives;277
20.3;Chapter 41: Niacin (B3) and Pantothenic Acid (B5);278
20.3.1;Overview;278
20.3.2;Niacin (Vitamin B3);278
20.3.3;Pantothenic Acid (Vitamin B5);280
20.3.4;Lipoic acid;282
20.3.5;Objectives;282
20.4;Chapter 42: Biotin and Pyridoxine (B6);284
20.4.1;Overview;284
20.4.2;Biotin;284
20.4.3;Pyridoxine (B6);287
20.4.4;Objectives;288
20.5;Chapter 43: Cobalamin (B12);289
20.5.1;Overview;289
20.5.2;Objectives;293
20.6;Chapter 44: Vitamin A;295
20.6.1;Overview;295
20.6.2;Fat-Soluble Vitamins;295
20.6.3;Vitamin A;295
20.6.4;Vitamin A Toxicity;297
20.6.5;Vitamin A and Vision;298
20.6.6;Vitamin A Deficiency;298
20.6.7;Objectives ;300
20.7;Chapter 45: Vitamin D;301
20.7.1;Overview;301
20.7.2;Vitamin D Toxicity;305
20.7.3;Vitamin D Deficiency;305
20.7.4;Objectives ;306
20.8;Chapter 46: Vitamin E;307
20.8.1;Overview;307
20.8.2;Vitamin E Deficiency;310
20.8.3;Objectives ;311
20.9;Chapter 47: Vitamin K;312
20.9.1;Overview;312
20.9.2;Vitamin K Deficiency;314
20.9.3;Vitamin K Toxicity;316
20.9.4;Objectives ;316
20.10;Chapter 48: Iron;317
20.10.1;Overview;317
20.10.2;Trace Elements;317
20.10.3;Iron (Fe);317
20.10.4;Iron Toxicity;320
20.10.5;Iron Deficiency;320
20.10.6;Objectives ;321
20.11;Chapter 49: Zinc;322
20.11.1;Overview;322
20.11.2;Zinc Toxicity;325
20.11.3;Objectives ;326
20.12;Chapter 50: Copper;327
20.12.1;Overview;327
20.12.2;Copper Deficiency;330
20.12.3;Copper Toxicity;330
20.12.4;Objectives ;331
20.13;Chapter 51: Manganese and Selenium;332
20.13.1;Overview;332
20.13.2;Manganese (Mn++);332
20.13.3;Selenium (Se);334
20.13.4;Objectives ;337
20.14;Chapter 52: Iodine and Cobalt;338
20.14.1;Overview;338
20.14.2;Iodine (I);338
20.14.3;Cobalt (Co);340
20.14.4;Objectives ;342
21;Section IV Examination Questions;343
22;Addendum to Section IV;351
23;Introduction to Section V;351
24;Section V: Lipid Metabolism;352
24.1;Chapter 53: Overview of Lipid Metabolism;353
24.1.1;Overview;353
24.1.2;Objectives ;357
24.2;Chapter 54: Saturated and Unsaturated Fatty Acids;358
24.2.1;Overview;358
24.2.2;Essential Fatty Acids;360
24.2.3;Objectives ;363
24.3;Chapter 55: Fatty Acid Oxidation;364
24.3.1;Overview;364
24.3.2;Mitochondrial ß-oxidation;367
24.3.3;Peroxisomal ß-oxidation;367
24.3.4;Objectives ;369
24.4;Chapter 56: Fatty Acid Biosynthesis;371
24.4.1;Overview;371
24.4.2;Fatty Acid Elongation Beyond Palmitate;373
24.4.3;NADPH Generation and FattyAcid Biosynthesis;374
24.4.4;Objectives ;376
24.5;Chapter 57: Triglycerides and Glycerophospholipids;378
24.5.1;Overview;378
24.5.2;Triglycerides;379
24.5.3;Glycerophospholipids;381
24.5.4;Objectives ;384
24.6;Chapter 58: Phospholipid Degradation;385
24.6.1;Overview;385
24.6.2;Ca++ Signaling;386
24.6.3;Phospholipids and the Ca++ Messenger System;387
24.6.4;Objectives ;390
24.7;Chapter 59: Sphingolipids;391
24.7.1;Overview;391
24.7.2;Sphingolipid Degradation;395
24.7.3;Objectives ;396
24.8;Chapter 60: Lipid Digestion;397
24.8.1;Overview;397
24.8.2;Emulsification of Dietary Fat;398
24.8.3;Enzymatic Hydrolysis of Dietary Lipids;398
24.8.4;Lipid Absorption in the Small Intestine;399
24.8.5;Mucosal Resynthesis of Dietary Lipids;399
24.8.6;Abnormalities in Lipid Digestion and Absorption;400
24.8.7;Objectives ;402
24.9;Chapter 61: Cholesterol;403
24.9.1;Overview;403
24.9.2;Cholesterol Biosynthesis;405
24.9.3;Abnormalities in the Plasma Cholesterol Concentration;408
24.9.4;Objectives ;408
24.10;Chapter 62: Bile Acids;410
24.10.1;Overview;410
24.10.2;Hepatic BA Biosynthesis;412
24.10.3;Bile Acid Actions in Bile, and in Luminal Contents of the Intestine;414
24.10.4;Intestinal Bile Acid Reabsorption and Enterohepatic Cycling;415
24.10.5;Regulation of Hepatic Bile Acid Biosynthesis;415
24.10.6;Bile Acid Signaling;416
24.10.7;Integration of Bile Acid Signaling, Hepatic Carbohydrate and Lipid Metabolism;416
24.10.8;Bile Acids as Therapeutic Agents;416
24.10.9;Objectives ;417
24.11;Chapter 63: Lipoprotein Complexes;419
24.11.1;Overview;419
24.11.2;Apoproteins;420
24.11.3;FFA-Albumin Complexes;421
24.11.4;Objectives ;423
24.12;Chapter 64: Chylomicrons;424
24.12.1;Overview;424
24.12.2;Objectives ;428
24.13;Chapter 65: VLDL, IDL, and LDL;429
24.13.1;Overview;429
24.13.2;Very Low-Density Lipoprotein (VLDL);429
24.13.3;Intermediate-Density (IDL), and Low-Density Lipoprotein (LDL);431
24.13.4;Objectives ;433
24.14;Chapter 66: LDL Receptors and HDL;434
24.14.1;Overview;434
24.14.2;Nature of the Low-Density Lipoprotein (LDL) Receptor;434
24.14.3;High-Density Lipoprotein (HDL);436
24.14.4;Objectives ;438
24.15;Chapter 67: Hyperlipidemias;440
24.15.1;Overview;440
24.15.2;Treatments for the Secondary Hyperlipidemias;444
24.15.3;Objectives ;445
24.16;Chapter 68: Eicosanoids I;447
24.16.1;Overview;447
24.16.2;Eicosanoid Degradation and Activity;449
24.16.3;Thromboxanes;450
24.16.4;Objectives ;451
24.17;Chapter 69: Eicosanoids II;452
24.17.1;Overview;452
24.17.2;Hydroperoxyeicosatetraenoic Acids (HPETEs) and Hydroxyeicosatetraenoic Acids (HETEs);452
24.17.3;Leukotrienes (LTs);452
24.17.4;Prostaglandins (PGs);454
24.17.5;Objectives ;456
24.18;Chapter 70: Lipolysis;457
24.18.1;Overview;457
24.18.2;Endocrine Control of Lipolysis;458
24.18.3;Glyceroneogenesis;460
24.18.4;Satiety;460
24.18.5;Lipolysis in Brown Adipose Tissue;461
24.18.6;Objectives ;462
24.19;Chapter 71: Ketone Body Formation and Utilization;463
24.19.1;Overview;463
24.19.2;Why Should one Lipid Fuel be Converted to Another in the Liver?;466
24.19.3;Ketone Body Utilization;467
24.19.4;Objectives ;469
24.20;Chapter 72: Fatty Liver Syndrome (Steatosis);471
24.20.1;Overview;471
24.20.2;Objectives ;475
25;Addendum to Section V;476
26;Introduction to Section VI;476
27;Section VI: Starvation & Exercise;477
27.1;Chapter 73: Starvation (Transition into the Postabsorptive Phase);478
27.1.1;Overview;478
27.1.2;The Insulin:Glucagon Ratio;479
27.1.3;Glucose Availability;481
27.1.4;The Initial Postabsorptive Phase of Starvation;481
27.1.5;Objectives ;483
27.2;Chapter 74: Starvation (The Early Phase);484
27.2.1;Overview;484
27.2.2;The Gluconeogenic Phase of Starvation;485
27.2.3;Objectives ;488
27.3;Chapter 75: Starvation (The Intermediate Phase);489
27.3.1;Overview;489
27.3.2;Objectives ;493
27.4;Chapter 76: Starvation (The Late Phase);495
27.4.1;Overview;495
27.4.2;Sequence of Body Protein Depletion;495
27.4.3;Starvation and Death;498
27.4.4;Starvation vs. Cachexia;498
27.4.5;The Survivors;498
27.4.6;Objectives ;499
27.5;Chapter 77: Exercise (Circulatory Adjustments and Creatine);500
27.5.1;Overview;500
27.5.2;Circulatory Adjustments to Exercise;501
27.5.3;Cardiac Adjustments to Exercise;501
27.5.4;Creatinine and Creatine;503
27.5.5;Objectives ;505
27.6;Chapter 78: Exercise (VO2(max) and RQ);506
27.6.1;Overview;506
27.6.2;Oxygen Consumption;506
27.6.3;The Respiratory Quotient (RQ);508
27.6.4;Alternative Techniques for Determining Fuel Utilization During Exercise;509
27.6.5;Objectives ;510
27.7;Chapter 79: Exercise (Substrate Utilization and Endocrine Parameters);511
27.7.1;Overview;511
27.7.2;Objectives ;515
27.8;Chapter 80: Exercise (Muscle Fiber Types and Characteristics);516
27.8.1;Overview;516
27.8.2;Skeletal Muscle Fiber Types;516
27.8.3;Muscles That Do Not Accumulate an O2 Debt;519
27.8.4;Muscle Atrophy during Immobilization;520
27.8.5;Objectives ;521
27.9;Chapter 81: Exercise (Athletic Animals);522
27.9.1;Overview;522
27.9.2;Muscle Fatigue;522
27.9.3;Athletic Animals;523
27.9.4;Benefits of Conditioning;525
27.9.5;Objectives ;526
28;Sections V and VI Examination Questions;527
29;Addendum to Section VI;545
30;Introduction to Section VII;545
31;Section VII: Acid-Base Balance;546
31.1;Chapter 82: The Hydrogen Ion Concentration;547
31.1.1;Overview;547
31.1.2;Hydrogen Ion Balance;548
31.1.3;Non-volatile Acid Production;549
31.1.4;Non-volatile Acid Input and Loss from the Body;550
31.1.5;Objectives ;551
31.2;Chapter 83: Strong and Weak Electrolytes;552
31.2.1;Overview;552
31.2.2;The Henderson-Hasselbalch Equation;554
31.2.3;Objectives ;556
31.3;Chapter 84: Protein Buffer Systems;557
31.3.1;Overview;557
31.3.2;The Hemoglobin (Hb–) Buffer System;558
31.3.3;Objectives ;561
31.4;Chapter 85: Bicarbonate, Phosphate, and Ammonia Buffer Systems;562
31.4.1;Overview;562
31.4.2;The Bicarbonate Buffer System;562
31.4.3;The Phosphate Buffer System;564
31.4.4;The Ammonia Buffer System;566
31.4.5;Objectives ;566
31.5;Chapter 86: Anion Gap;568
31.5.1;Overview;568
31.5.2;Plasma Anion Gap (AG);568
31.5.3;Urinary Anion Gap (UAG);570
31.5.4;Objectives ;572
31.6;Chapter 87: Metabolic Acidosis;574
31.6.1;Overview;574
31.6.2;Effects of Chronic Acidemia on Bone;579
31.6.3;Objectives ;579
31.7;Chapter 88: Diabetes Mellitus (Metabolic Acidosis and Potassium Balance);581
31.7.1;Overview;581
31.7.2;Metabolic Acidosis and K+ Balance;582
31.7.3;Endocrine Influences on K+ Balance;585
31.7.4;Objectives ;588
31.8;Chapter 89: Metabolic Alkalosis;589
31.8.1;Overview;589
31.8.2;Metabolic Alkalosis and K+ Balance;592
31.8.3;Volume-Resistant Metabolic Alkalosis;594
31.8.4;Objectives ;595
31.9;Chapter 90: Respiratory Acidosis;597
31.9.1;Overview;597
31.9.2;Medullary Chemoreceptors;600
31.9.3;Objectives ;602
31.10;Chapter 91: Respiratory Alkalosis;603
31.10.1;Overview;603
31.10.2;Mixed Acid-base Disturbances;606
31.10.3;Objectives ;608
31.11;Chapter 92: Strong Ion Difference (SID);609
31.11.1;Overview;609
31.11.2;Plasma Proteins and Phosphates;610
31.11.3;Free Water Abnormalities;610
31.11.4;Base Excess (BE) and Base Deficit (-BE);611
31.11.5;Example Problem;611
31.11.6;Objectives ;615
31.12;Chapter 93: Alkalinizing and Acidifying Solutions;619
31.12.1;Overview;619
31.12.2;Alkalinizing Solutions;619
31.12.3;Acidifying Solutions;622
31.12.4;Objectives ;624
31.13;Chapter 94: Dehydration/Overhydration;625
31.13.1;Overview;625
31.13.2;Hypertonic Dehydration;625
31.13.3;Isotonic Dehydration;626
31.13.4;Hypotonic Dehydration;627
31.13.5;Indicators of Hypovolemia;628
31.13.6;Overhydration;628
31.13.7;Expansion of the ECF Volume;629
31.13.8;Objectives;630
32;Section VII Examination Questions;631
33;Epilog;639
34;Case Studies;640
34.1;Case Study #1: Ethylene Glycol;641
34.1.1;Questions;641
34.1.2;Answers;641
34.2;Case Study #2: Phosphofructokinase (PFK);645
34.2.1;Questions;645
34.2.2;Answers;646
34.3;Case Study #3: Inflammatory Bowel Disease (IBD), Endocarditis and Cardiac Ischemia;648
34.3.1;Questions;648
34.3.2;Answers;649
34.4;Case Study #4: Portosystemic Vascular Shunt (PSS);653
34.4.1;Questions;653
34.4.2;Answers;653
34.5;Case Study #5: Diabetes Mellitus (DM);657
34.5.1;Questions;657
34.5.2;Answers;658
34.6;Case Study #6: Feline Lower Urinary Tract Disease(FLUTD);662
34.6.1;Questions;662
34.6.2;Answers;662
35;Appendix;666
36;Abbreviations;674
37;References;688
38;Index;696
Chapter 1 Chemical Composition of Living Cells
Abstract
Most all diseases in animals are manifestations of abnormalities in biomolecules, chemical reactions, or biochemical pathways, so understanding the macromolecules within cells is critical. Hydrogen, oxygen, nitrogen, carbon, sulfur and phosphorus normally make up more than 99% of the mass of living cells. This chapter aims to give an overview of critical macromolecules, while going into more detail for the general structure and important details about intra and extracellular proteins; homogenous from heterogenous polymers; compound, simple and derived lipids. It also aims to allow readers to articulate how and why the inorganic elements are essential to life, as well as understand a basic understanding of physiological chemistry is fundamental to a clinical understanding of disease processes. Keywords Lipids Polysaccharides Proteins Nucleic Acids Macromolecules biochemical pathways biomolecules OBJECTIVES • Identify six elements that normally comprise over 99% of the living cell mass. • Summarize the approximate chemical composition of a living cell. • Give examples of functionally important intra- and extracellular proteins. • Distinguish homogenous from heterogenous polymers, and give some examples. • Understand basic differences between compound, simple and derived lipids. • Indicate how and why the inorganic elements are essential to life. • Recognize why a basic understanding of physiological chemistry is fundamental to a clinical understanding of disease processes. Overview • Hydrogen, oxygen, nitrogen, carbon, sulfur and phosphorus normally make up more than 99% of the mass of living cells. • Ninety-nine percent of the molecules inside living cells are water molecules. • Cells normally contain more protein than DNA. • Homogenous polymers are noninformational. • All non-essential lipids can be generated from acetyl-CoA. • Like certain amino acids and unsaturated fatty acids, various inorganic elements are dietarily “essential.” • Most all diseases in animals are manifestations of abnormalities in biomolecules, chemical reactions, or biochemical pathways. All living organisms, from microbes to mammals, are composed of chemical substances from both the inorganic and organic world, that appear in roughly the same proportions, and perform the same general tasks. Hydrogen, oxygen, nitrogen, carbon, phosphorus, and sulfur normally make up more than 99% of the mass of living cells, and when combined in various ways, form virtually all known organic biomolecules. They are initially utilized in the synthesis of a small number of building blocks that are, in turn, used in the construction of a vast array of vital macromolecules (Fig 1-1). Figure 1-1 There are four general classes of macromolecules within living cells: nucleic acids, proteins, polysaccharides, and lipids. These compounds, which have molecular weights ranging from 1 × 103 to 1 × 106, are created through polymerization of building blocks that have molecular weights in the range of 50 to 150. Although subtle differences do exist between cells (e.g., erythrocyte, liver, muscle or fat cell), they all generally contain a greater variety of proteins than any other type of macromolecule, with about 50% of the solid matter of the cell being protein (15% on a wet-weight basis). Cells generally contain many more protein molecules than DNA molecules, yet DNA is typically the largest biomolecule in the cell. About 99% of cellular molecules are water molecules, with water normally accounting for approximately 70% of the total wet-weight of the cell. Although water is obviously important to the vitality of all living cells, the bulk of our attention is usually focused on the other 1% of biomolecules. Data in Table 1-1 regarding the chemical composition of the unicellular Escherichia coli (E. coli) are not greatly different for multicellular organisms, including mammals. Each E. coli, and similar bacterium, contains a single chromosome; therefore, it has only one unique DNA molecule. Mammals, however, contain more chromosomes, and thus have different DNA molecules in their nuclei. Table 1-1 Approximate Chemical Composition of a Rapidly Dividing Cell (E. coli) Water 70 1 Nucleic acids DNA 1 1 RNA 6 Ribosomal 3 Transfer 40 Messenger 1000 Nucleotides and metabolites 0.8 200 Proteins 15 2000-3000 Amino acids and metabolites 0.8 100 Polysaccharides 3 200 (Carbohydrates and metabolites) Lipids and metabolites 2 50 Inorganic ions 1 20 (Major minerals and trace elements) Others 0.4 200 100 Data from Watson JD: Molecular Biology of the Gene, 2nd ed., Philadelphia, PA: Saunders, 1972 Nucleic Acids
Nucleic acids are nucleotide polymers (from the Greek word poly, meaning “several,” and mer, meaning “unit”), that store and transmit genetic information. Only 4 different nucleotides are used in nucleic acid biosynthesis. Genetic information contained in nucleic acids is stored and replicated in chromosomes, which contain genes (from the Greek word gennan, meaning “to produce”). A chromosome is a deoxyribonucleic acid (DNA) molecule, and genes are segments of intact DNA. The total number of genes in any given mammalian cell may total several thousand. When a cell replicates itself, identical copies of DNA molecules are produced; therefore the hereditary line of descent is conserved, and the genetic information carried on DNA is available to direct the occurrence of virtually all chemical reactions within the cell. The bulk of genetic information carried on DNA provides instructions for the assembly of every protein molecule within the cell. The flow of information from nucleic acids to protein is commonly represented as DNA ? messenger ribonucleic acid (mRNA) ? transfer RNA (tRNA) ? ribosomal RNA (rRNA) ? protein, which indicates that the nucleotide sequence in a gene of DNA specifies the assembly of a nucleotide sequence in an mRNA molecule, which in turn directs the assembly of the amino acid sequence in protein through tRNA and rRNA molecules. Proteins
Proteins are amino acid polymers responsible for implementing instructions contained within the genetic code. Twenty different amino acids are used to synthesize proteins, about half are formed as metabolic intermediates, while the remainder must be provided through the diet. The latter group is referred to as “essential” amino acids (see Chapter 3). Each protein formed in the body, unique in its own structure and function, participates in processes that characterize the individuality of cells, tissues, organs, and organ systems. A typical cell contains thousands of different proteins, each with a different function, and many serve as enzymes that catalyze (or speed) reactions. Virtually every reaction in a living cell requires an enzyme. Other proteins transport different compounds either outside or inside cells {e.g., lipoproteins and transferrin (an iron-binding protein) in plasma, or bilirubin-binding proteins in liver cells}; some act as storage proteins (e.g., myoglobin binds and stores O2 in muscle cells); others as defense proteins in blood or on the surface of cells (e.g., clotting proteins and immunoglobulins); others as contractile proteins (e.g., the actin, myosin and troponin of skeletal muscle fibers); and others are merely structural in nature (e.g., collagen and elastin). Proteins, unlike glycogen and triglyceride, are usually not synthesized and stored as nonfunctional entities. Polysaccharides
Polysaccharides are polymers of simple...
