Estrogen receptor binding radiopharmaceuticals: II. Tissue distribution of 17 alpha-methylestradiol in normal and tumor-bearing rats.

Abstract

Tritiated 17 alpha-methylestradiol was synthesized to investigate the potential of the carbon-11-labeled analog as an estrogen-receptor-binding radiopharmaceutical. In vitro, 17 alpha-methylestradiol is bound with high affinity to the cytoplasmic estrogen receptor from rabbit uterus (Kd = 1.96 x 10(-10)M), and it sediments as an 8S hormone-receptor complex in sucrose gradients. The compound shows specific uptake in the uterus of the adult rat, within 1 hr after injection. After 30 min the uterine uptake was 1.73% dose/g. In female rats bearing DMBA-induced tumors, specific uterine and tumor uptakes were observed, although at 30 min the tumor uptake was only 23-30% of the uptake in the uterus. Tritiated 17 alpha-methylestradiol with a specific activity of 6 Ci/mmole showed a similar tissue distribution. Our results indicate that 17 alpha-methylestradiol is promising as an estrogen-receptor-binding radiopharmaceutical.

• Authors: A Feenstra, W Vaalburg, G M Nolten, S Reiffers, A G Talma, T Wiegman, H D van der Molen, M G Woldring
• Journal: Journal of nuclear medicine : official publication, Society of Nuclear Medicine (J Nucl Med) Vol. 24 Issue 6 Pg. 522-8 (Jun 1983) ISSN: 0161-5505 [Print] United States
• PMID: 6406650 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Receptors, Estrogen
• 17-methylestradiol
• Estradiol
• 9,10-Dimethyl-1,2-benzanthracene

Topics

• 9,10-Dimethyl-1,2-benzanthracene
• Animals
• Estradiol (analogs & derivatives, metabolism)
• Female
• Mammary Neoplasms, Experimental (chemically induced, metabolism)
• Rats
• Rats, Inbred Strains
• Receptors, Estrogen (metabolism)
• Tissue Distribution
• Uterus (metabolism)