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Human Placental Cytochrome P-450: Microsomal Preparation and Purification

  • Charles W. Fisher
  • John J. Moore
Chapter
Part of the Trophoblast Research book series (TR)

Abstract

The human placenta contains several microsomal oxidases important in the oxidation of steroids and drugs (Pelkonen and Pasanen, 1984; Pelkonen, 1980; Namkung et al., 1983). An important function of placental cytochrome P-450 is the aromatization of steroids (Meigs and Ryan, 1968). This aromatase activity is induced by the cAMP analog, dibutyryl cAMP, and theophylline indicating a possible control by kinase (Bellino and Hussa, 1978). Further study of the regulation of this and other cytochrome P-450 activities requires the purification of the terminal oxidase, cytochrome P-450, and the associated cytochrome c reductase. Methods of purifying cytochrome P-450 (Pasanen and Pelkonen, 1981; Pelkonen and Pasanen, 1982) and cytochrome c reductase (Bellino, 1982; Yasukochi and Masters, 1976) from human placenta have been reported. However, due to the low specific content of cytochrome P-450 (0.05–0.15 nmol/mg) in human placental microsomes only small amounts of cytochrome P-450 or the reductase can be obtained from a single placenta.

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Copyright information

© Springer Science+Business Media New York 1987

Authors and Affiliations

  • Charles W. Fisher
    • 1
  • John J. Moore
    • 1
  1. 1.Department of PediatricsCase Western Reserve University Cleveland Metropolitan General HospitalClevelandUSA

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