The content of non-esterified fatty acids in rat myocardial tissue. A comparison between the Dole and Folch extraction procedures.
Oliver and coworkers hypothesized that under certain circumstances NEFA (non-esterified fatty acids = FFA = free fatty acids) might be toxic for myocardial function. Unambiguous conclusions on the putative detrimental effect of intracellularly localized NEFA are hampered by contradictory values published for the NEFA content in normoxic myocardial tissue. From studies in which the assay procedures were carefully evaluated, one might conclude that the NEFA content in dog and rat myocardial tissue will not exceed 60 and 150 nmol/g wet weight, respectively. However, recently Victor and coworkers found considerably higher NEFA values in rat myocardial tissue and suggested that the low NEFA values as measured, for example, in our laboratory, resulted from incomplete extraction when the Folch medium was applied instead of the Dole mixture. Since Victor and coworkers used a modified Dole procedure as described by Hagenfeldt, we evaluated the Folch procedure as well as the original Dole technique and the modified version. Our findings indicate that the lower values found by the Folch technique are more likely to be correct. Incomplete extraction of NEFA did not occur, whereas hydrolysis and transmethylation of phospholipid fatty acids were observed in case of the (modified) Dole procedures.
D000818:Animals; D005069:Evaluation Studies as Topic; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D008722:Methods; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D011917:Rats, Inbred Lew
D005230:Fatty Acids, Nonesterified