This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Irving, C. C. Articles by Williard, R. F. Search for Related Content PubMed PubMed Citation Articles by Irving, C. C. Articles by Williard, R. F.

On the in Vivo Protein Binding of 1-Hydroxy-2-acetylaminofluorene-1-C¹⁴ in the Rat^*

( Radioisotope Service, Veterans Administration Medical Teaching Group Hospital, and Department of Biochemistry, University of Tennessee Medical Units, Memphis, Tennessee)

At 24 hours after administration of a single dose of 3–4 mg. of 1-hydroxy-2-acetylaminofluorene-1-C¹⁴ (1-hydroxy-AAF-1-C¹⁴) intraperitoneally to rats, 75 per cent of the dose had been excreted in the urine and feces. About 5 per cent of the injected radioactivity was present in the gastrointestinal contents, and only 1–2 per cent remained in the tissues of the rat.

Radioactivity equivalent to 15–19 mµmoles of 1-hydroxy-AAF-1-C¹⁴ per gm. of protein was bound to tissue proteins of the liver, lung, and plasma. Bound radioactivity in the kidney was equivalent to 7 mµmoles of the metabolite per gm. of protein, whereas proteins of the gastrointestinal tract, heart, spleen, bladder, and brain contained radioactivity equivalent to 0.1–5 mµmoles of 1-hydroxy-AAF-1-C¹⁴ per gm.

Administration of the 1-hydroxy-AAF-1-C¹⁴ by oral, intraperitoneal, or subcutaneous routes did not appear to result in appreciable differences in the degree or distribution of protein-bound radioactivity. The amount of radioactivity bound to protein in the various tissues examined was essentially constant from 12 to 48 hours after administration of the 1-hydroxy-AAF-1-C¹⁴.

In comparative studies, more protein-bound radioactivity was found in most tissues of the rat following intraperitoneal administration of 2-acetylaminofluorene-9-C¹⁴ (AAF-9-C¹⁴) than was found following injection of equivalent doses of 1-hydroxy-AAF-1-C¹⁴. Bound radioactivity equivalent to 68 mµmoles of AAF per gm. of liver protein and 92 mµmoles of AAF per gm. of plasma protein was found. Bound radioactivity in other tissues following administration of AAF-9-C¹⁴ was equivalent to 1–24 mµmoles of AAF per gm. of tissue protein.

^* This investigation was supported in part by a research grant (CA-05490) from the National Cancer Institute, U. S. Public Health Service.

The nomenclature used in this paper is given below, followed in each case by the Chemical Abstracts nomenclature in brackets:

2-acetylaminofluorene [N-2-fluorenylacetamide]

x-hydroxy-2-acetylaminofluorene [N-(x-hydroxy-2-fluorenyl)-acetamide]

N-hydroxy-2-acetylaminofluorene [N-hydroxy-N-2-fluorenyl-acetamide].

Received 7/15/63.