Human rectal absorption of short- and medium-chain C2-C10 fatty acids.
BACKGROUND
Current knowledge on the colonorectal absorption of medium-chain fatty acids is limited. The purpose of the present study was to evaluate and compare the human rectal absorption of short- and medium-chain C2-C10 fatty acids in healthy volunteers.


METHODS
Dialysis bags containing 20 mmol x l(-1) of the fatty acids acetate, butyrate, hexanoate, octanoate, or decanoate in a phosphate-buffered (pH neutral) isoosmotic electrolyte solution were placed in the rectum for 30 min in 14 healthy volunteers. Absorption rates were calculated for all fatty acids, sodium, potassium, and water.


RESULTS
Absorption rates of the fatty acids acetate, butyrate, hexanoate, octanoate or decanoate were the same (1.9 +/- 0.1 = 2.5 +/- 0.2 = 1.7 +/- 0.2 = 1.9 +/- 0.2 = 2.2 +/- 0.1 micromol x cm(-2) x h(-1) (mean +/- standard error of the mean), respectively; P = 0.24).


CONCLUSIONS
Medium-chain fatty acids were absorbed in the human rectum at a rate similar to that for short-chain fatty acids. If results can be applied to the human colon, colonic absorption of medium-chain fatty acids could possibly become an important secondary site of absorption in abnormal intestinal conditions such as massive small-intestinal resection or malabsorption syndromes.
Dept. of Medicine CA 2121, Copenhagen University Hospital, Rigshospitalet, Denmark.
J
J
Jørgensen
K
K
Holtug
P B
PB
Jeppesen
P B
PB
Mortensen
D000285:Administration, Rectal; D000328:Adult; D005227:Fatty Acids / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005232:Fatty Acids, Volatile / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007408:Intestinal Absorption / Q000502:physiology*; D007413:Intestinal Mucosa / Q000378:metabolism; D007552:Isotonic Solutions / Q000008:administration & dosage / Q000493:pharmacokinetics; D008297:Male; D012007:Rectum / Q000378:metabolism
D005227:Fatty Acids; D005232:Fatty Acids, Volatile; D007552:Isotonic Solutions