UPTAKE, INTER-ORGAN DISTRIBUTION AND METABOLISM OF DIETARY PUTRESCINEIN THE RAT

The movement of a single dose of C-14-putrescine in the lumen of the r at gastrointestinal tract was followed for 3 hours after intragastric intubation. Putrescine progressed in the gut lumen in a wave-like fash ion and was absorbed in the small bowel. Maximal uptake was observed a t 2 hours; therefore, this time-point was selected to measure the conc entration dependency of putrescine uptake by the small intestine and d istribution between the vital organs in a wide concentration range (1/ 10 to 100 times the dietary input). Putrescine uptake by the small bow el was likely to be by passive diffusion, because the absorption was i n proportion to input. The fate of putrescine was determined in the pl asma, small bowel, liver, and skeletal muscle by measuring the radioac tivity of the polyamines, their acetyl derivatives, and amino acids at physiologic concentrations. It appears that approximately 10% of the dietary input reaches the putrescine body pool. (J. Nutr. Biochem. 9:3 32-338, 1998) (C) Elsevier Science Inc. 1998.