Effects of Exogenous Steroids on the Adrenal Plasma Membrane Alteration of Steroidogenesis and Cell Morphology
Description: Using cultured Y-1 mouse adrenal tumor cells which produce the steroid 20(-hydroxypregn-4-en-3-one (20-DHP), it was found that 10-5 M corticosterone and deoxycorticosterone increased basal and inhibited ACTH-induced 20-DHP production. The steroid effects were concentration-dependent, reversible, and specific since six other steroids did not stimulate steroidogenesis and varied in their ability to inhibit ACTH-induced steroidogenesis. Cytochalasin D inhibited steroid-stimulated 20-DHP production, suggesting a mechanism of steroid stimulation similar to that of ACTH. Steroidogenesis stimulated by cholera toxin, (Bu) 2 cAMP, or pregnenolone was not inhibited by exogenous steroid; corticosterone increased basal and inhibited ACTH-induced intracellular cAMP production. Steroids altered cell surface morphology. These findings suggest that steroids alter adrenal steroidogenesis by acting within the plasma membrane.
Date: August 1982
Creator: Mattson, Mark Paul
Item Type: Thesis or Dissertation