Mitochondrial benzodiazepine receptors regulate steroid biosynthesis.

Published

Journal Article

Recent observations on the steroid synthetic capability within the brain open the possibility that benzodiazepines may influence steroid synthesis in nervous tissue through interactions with peripheral-type benzodiazepine recognition sites, which are highly expressed in steroidogenic cells and associated with the outer mitochondrial membrane. To examine this possibility nine molecules that exhibit a greater than 10,000-fold difference in their affinities for peripheral-type benzodiazepine binding sites were tested for their effects on a well-established steroidogenic model system, the Y-1 mouse adrenal tumor cell line. 4'-Chlorodiazepam, PK 11195, and PK 14067 stimulated steroid production by 2-fold in Y-1 cells, whereas diazepam, flunitrazepam, zolpidem, and PK 14068 displayed a lower (1.2- to 1.5-fold) maximal stimulation. In contrast, clonazepam and flumazenil did not stimulate steroid synthesis. The potencies of these compounds to inhibit 3H-labeled PK 11195 binding to peripheral-type benzodiazepine recognition sites correlated (r = 0.985) with their potencies to stimulate steroid production. Similar findings were observed in bovine and rat adrenocortical cell preparations. These results suggest that ligands of the peripheral-type benzodiazepine recognition site acting on this mitochondrial receptor can enhance steroid production. This action may contribute specificity to the pharmacological profile of drugs preferentially acting on the benzodiazepine recognition site associated with the outer membrane of certain mitochondrial populations.

Full Text

Duke Authors

Cited Authors

  • Mukhin, AG; Papadopoulos, V; Costa, E; Krueger, KE

Published Date

  • December 1989

Published In

Volume / Issue

  • 86 / 24

Start / End Page

  • 9813 - 9816

PubMed ID

  • 2574864

Pubmed Central ID

  • 2574864

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.86.24.9813

Language

  • eng

Conference Location

  • United States