Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

The function of NADH-semidehydroascorbate reductase and ascorbic acid in corticosteroid hydroxylation.

R D Natarajan1, B W Harding

  • 1Department of Medicine, LAC/USC Medical Center, Los Angeles 90033.

Molecular and Cellular Endocrinology
|September 1, 1987
PubMed
Summary

An ascorbate-dependent electron transport pathway (ETP) supplies reducing equivalents to mitochondrial hydroxylases in the adrenal cortex. This pathway is crucial for maximal hydroxylation activity in vivo.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

12-Lipoxygenase products increase monocyte:endothelial interactions.

Advances in experimental medicine and biology·2000
Same author

Evidence that glucose increases monocyte binding to human aortic endothelial cells.

Diabetes·1994
Same author

Intracellular free magnesium deficiency plays a key role in increased platelet reactivity in type II diabetes mellitus.

Diabetes care·1992
Same author

Gonadotropin releasing hormone activates the lipoxygenase pathway in cultured pituitary cells: role in gonadotropin secretion and evidence for a novel autocrine/paracrine loop.

Biochemistry·1992
Same author

Cholesterol side chain cleavage in rat adrenal supported by outer mitochondrial membrane NADH-semidehydroascorbate reductase.

The Journal of biological chemistry·1985
Same author

Characterization of cell surface adenosine 3',5'-monophosphate-binding proteins in Y-1 mouse adrenal tumor cells.

Endocrinology·1985

Area of Science:

  • Biochemistry
  • Mitochondrial Physiology
  • Steroidogenesis

Background:

  • NADH-semidehydroascorbate reductase and ascorbate form an electron transport pathway (ETP) supplying reducing equivalents to cytochrome P-450scc in rat adrenal mitochondria.
  • The role of this ascorbate-dependent ETP in other mitochondrial hydroxylases was previously unclear.

Purpose of the Study:

  • To investigate the role of the ascorbate-dependent ETP in supplying reducing equivalents to cytochrome P-450(11 beta/18) in adrenal mitochondria.
  • To compare the efficiency of the ascorbate-dependent ETP with the classical pathway for mitochondrial hydroxylation.
  • To reconstitute the ascorbate-dependent 11 beta/18-hydroxylase activity.

Main Methods:

  • Studied ascorbate-dependent electron transport in rat adrenal and bovine adrenal cortex mitochondria.

Related Experiment Videos

  • Assessed 11 beta- and 18-hydroxylation rates supported by the ascorbate-dependent ETP and TCA cycle intermediates.
  • Partially reconstituted 11 beta/18-hydroxylase activity using purified mitochondrial membranes and sonified mitochondrial supernatant.

    • Main Results:

    • The ascorbate-dependent ETP supplies reducing equivalents to cytochrome P-450(11 beta/18) in both rat and bovine adrenal mitochondria.
    • This pathway's activity depends on catalase or cold shock treatment of mitochondria.
    • The ascorbate-dependent pathway may be essential for maximal in vivo hydroxylation by mitochondrial hydroxylases.
    • Reconstituted preparations lacking catalase or cold shock treatment showed restored activity.

    Conclusions:

    • The ascorbate-dependent ETP is a significant pathway for supplying reducing equivalents to mitochondrial hydroxylases in the adrenal cortex.
    • This pathway is likely essential for maximal steroid 11 beta- and 18-hydroxylation in vivo.
    • The reconstituted system provides insights into the components required for this specific hydroxylase activity.