CONTENTS 



Page 



Introduction 1 



ChemicaJ. natiore of trimethylamine oxide 1 



Occurrence 1 



Occurrence in marine animals 2 



Occurrence in fresh-water animals 11 



Physiological and biochemical significance of trimethyl- 

 amine oxide 11 



Osmoregulation and exci'etion 11 



KLasmobranchs 11 



Teleosts 13 



Other marine animals 1^ 



Fresh-water teleosts lit- 



Nitrogen metabolism Ik 



Trimethylamine oxide as a product of protein 



metabolism l^t- 



Trimethylamine oxide from an exogenous source. . 15 

 Trimethylamine oxide as a methyl donor and its 



relationship to other methylated compounds . . l6 



Other tertiary amine oxides l6 



Formation of trimethylamine oxide in mammals as 

 a result of degradation of choline or choline - 



containing derivatives . l6 



Summary l6 



Literature cited 17 



TABLES 



No. 



1. Trimethylamine oxide content of marine axiimals ... 3 



2. Trimethylamine oxide content of fresh-water 



animals 12 



3. Summary of trimethylamine oxide content of marine 



and fresh-water animals 13 



ABSTRACT 



Some pertinent information on the occurrence of trimethylamine 

 oxLde in marine animals is reported^ and the current ideas on the 

 origin and function of the oxide are examined. 



11 



