The effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the uptake, distribution and excretion of a single oral dose of [11,12-3H]retinyl acetate and on the vitamin A status in the rat.

Abstract

TCDD (2,3,7,8-Tetrachlorodibenzo-p-dioxin, 10 micrograms/kg body weight, p.o.) was given to male Sprague-Dawley rats 4 d before the oral administration of a physiological dose of [11,12-3H]retinyl acetate (RA). The rats were kept in metabolic cages for up to 192 h after RA administration. Radioactivity and/or vitamin A were determined in tissues and excreta. TCDD-pretreated and control rats excreted 41 and 23%, respectively, of the radioactivity of RA during the 192 h after administration. In control animals, 30% of the radioactivity of RA entered the liver within 6 h, the stores reaching 42% after 192 h. Maximum storage in TCDD-treated rats was 13% and after 192 h only 9% of the dose remained. A lag period of 12-24 h preceded the TCDD-induced increase in renal (175-671%) and serum (85-145%) radioactivity. In TCDD-treated rats less radioactivity was found in the intestine (45-79% decrease) and adrenals (14-73% decrease). Relative to the total body content, significantly more radioactivity was found in the kidney, serum, testes and epididymis of TCDD-treated rats. The decrease in vitamin A content after TCDD-treatment was 39-53% in the liver, 19-67% in the intestine and 18-44% in the epididymis. The kidneys of TCDD-treated rats contained more vitamin A (3-30 times more). TCDD treatment initially increased (42%) and later decreased (40%) the vitamin A content in the thymus as compared to controls. Pretreatment with a single low dose of TCDD thus affects both storage and excretion of radioactivity from newly administered RA as well as the vitamin A content in several tissues.

• Authors: H Håkansson, U G Ahlborg
• Journal: The Journal of nutrition (J Nutr) Vol. 115 Issue 6 Pg. 759-71 (Jun 1985) ISSN: 0022-3166 [Print] United States
• PMID: 3998869 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Dioxins
• Diterpenes
• Polychlorinated Dibenzodioxins
• Retinyl Esters
• Vitamin A
• retinol acetate

Topics

• Administration, Oral
• Adrenal Glands (metabolism)
• Animals
• Dioxins (pharmacology)
• Diterpenes
• Feces (analysis)
• Intestinal Mucosa (metabolism)
• Kidney (metabolism)
• Liver (metabolism)
• Lymphoid Tissue (metabolism)
• Male
• Organ Size (drug effects)
• Polychlorinated Dibenzodioxins (pharmacology)
• Rats
• Rats, Inbred Strains
• Retinyl Esters
• Testis (metabolism)
• Tissue Distribution (drug effects)
• Vitamin A (analogs & derivatives, metabolism)