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The Steroidogenic Response of Large and Small Luteal Cells to Dibutyryl cAMP and 25-OH-Cholesterol

  • Carol J. Smith
  • R. Sridaran

Abstract

The mammalian corpus luteum consists of two major types of steroidogenic cells based upon size and histological characteristics. In this study, large (>22µ) and small (12–21 |i) luteal cells from day 8 pregnant rats were separated by elutriation after enzyme dissociation. Aliquots of cells were incubated for 4 h at 37°C in Medium 199 (control), medium plus dibutyryl cAMP (cAMP) at 0.5 mM or 5 mM, or medium plus 10 (µg/ml 25-OH-cholesterol. Production of progesterone, testosterone, and estradiol was measured by radioimmunoassay (RIA). Both cell types showed an increase in progesterone and estradiol synthesis when incubated with cAMP; however, the large luteal cells responded to a tenfold lower dose (0.5 mM) of cAMP than did the small cells which required 5 mM for stimulation. CAMP (5 mM) also resulted in an increase of testosterone release from small luteal cells. Progesterone synthesis was enhanced by 25-OH-cholesterol in the large luteal cells. These results suggest that the two cell types differ functionally with respect to steroidogenesis during pregnancy, and that the large luteal cells may be a major source of progesterone production.

Keywords

Luteinizing Hormone Corpus Luteum Luteal Cell Progesterone Production Dibutyryl cAMP 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Carol J. Smith
    • 1
  • R. Sridaran
    • 1
  1. 1.Department of PhysiologyMorehouse School of MedicineAtlantaUSA

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