Metabolism of stearate-l-C14 in the isolated cow's udder*

SUMMARY One-half of a lactating cow's udder was perfused with heparinized and oxygenated cow's blood at 38" for 150 minutes; 30 minutes after the onset of the perfusion, approximately 200 pc of stearate-l-C" (albumin-bound) was added to the perfusing blood, together with inactive acetate and glucose. Almost all the blood's stearate-l-C1* was absorbed by the gland, and much of the added Cl4 was recovered horn the glycerides of the udder tissue. Stearic acid and oleic acid of the glycerides showed significant specific activities. Negligible activities were detected in the shorter chain fatty acids of the glycerides, in citric acid, and in CO*, indicating that stearic acid was broken down to only a very small extent.