Peripheral benzodiazepine receptors (PBR) in the ovary, oviduct, uterus, and kidney of immature rats were studied under short- and long-term treatment with testosterone (T), progesterone (P4), and diethylstilbestrol (DES). A significant increase in PBR specific binding was observed after 4 days′ treatment with T in the ovary (1.6-fold), oviduct (2.0-fold), and uterus (1.4-fold) compared with intact rats. Four days′ treatment with P4 increased PBR specific binding in the ovary (1.5-fold), but no changes were detected in the oviduct or uterus. In contrast, PBR specific binding was significantly reduced by 10 days′ treatment with T or P4: 40 and 12%, respectively, in the ovary and 35 and 40%, respectively, in the oviduct. Ten days′ treatment with T reduced PBR specific binding in the uterus by 25%, but the same interval of treatment with P4 did not alter specific binding in the uterus. Four or 10 days′ treatment wit DES signuificantly increased PBR specific binding in the ovary (1.5-fold), oviduct (2.4-fold), and uterus (1.9-fold). Scatchard analysis revealed that the changes in the PBR specific binding were due to a change in PBR density values rather than PBR affinity values. No change in PBR specific binding was found in the kidney following any of these treatments. Taken together, it is suggested that PBR density in the ovary is altered by exogenously administered steroids that usually are biosynthesized in the ovary. Additionally, the altered PBR density in the oviduct and uterus via the various steroids employed may imply that changes occurring in ovarian steroidogenesis should affect PBR density in these organs.
Bibliographical noteFunding Information:
This paper is submitted in partial fulfillment of the requirements for the D.Sc. degree of Z.A. at the Technion-Israel Institute of Technology. We thank Miss Efrat Zlotkin for technical assistance and Miss Ruth Singer for typing and editing the manuscript. The work was supported by Grant 87-00234 to M.G. from the U.S.-Israel Binational Science Foundation.
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ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology
- Pharmacology, Toxicology and Pharmaceutics (all)