XVlll CONTENTS 



III. The Oxidation and Metabolism of Triglycerides, Fatty Acids, and 



Glycerol in the Animal Body (continued) 



d. Interconversions of the More Highly Unsaturated Acids 187 



e. The MetaboUsm of Polyunsaturated Acids as Related to the 



State of Oxidation 188 



(6) The Site of Oxidation of Fats in the Animal Body 189 



a. The Liver as the Site of Oxidation 189 



(a) The Nature of Liver Fats 190 



a'. Phospholipids 190 



b'. Unsaturation of Liver Lipids 190 



c'. Saturation of Liver Lipids 192 



(b) Fat Transport to and from the Liver 192 



(c) Ketone Body Formation in the Liver 193 



(d) Fat Turnover in the Liver 194 



b. Extrahepatic Oxidation of Fat 194 



(a) Extrahepatic Synthesis of Acetone Bodies 196 



(b) The Utilization of Ketone Bodies by Extrahepatic Tissues. 198 



(7) Factors Affecting Fat Oxidation 199 



(8) The Inhibition of Fatty Acid Oxidation 203 



(9) The Oxidation and Metabolism of Parenterally Administered Fats 203 



a. Subcutaneous Administration of Fat 204 



b. Intravenous Administration of Fat 204 



(a) Cause of Toxicity of Fat Preparations for Intravenous 



Use 204 



(b) Methods for Stabilizing Emulsions 205 



(c) Results Obtained with Recent Fat Emulsions 206 



3. The Oxidation and Metabolism of Glycerol 207 



IV. The Question of the Conversion of Fat to Carbohydrate 211 



1. The Transformation of Glycerol to Glucose 212 



(1) Quahtative Studies 212 



(2) Quantitative Studies 213 



2. The Transformation of Fatty Acids with Odd-Numbered Carbons to 



Carbohydrate 214 



3. The Transformation of Fatty Acids with Even-Numbered Carbons to 



Carbohydrate 215 



(1) Experiments Not Involving the Use of Isotopes 215 



a. Acetic Acid as a Possible Source of Carbohydrate 215 



b. Butyric Acid as a Possible Source of Carbohydrate 217 



c. liOng-Chain Acids and Fats as Possible Sources of Carbo- 



hydrate 219 



(2) Experiments Involving the Use of Isotopes 221 



4. General Experimental Evidence on the Question of the Conversion of 



Fat to Carboh>'drate 223 



(1) D:N Ratio 223 



(2) Respiratory Quotient 225 



(3) The Importance of Epineplirine 228 



