Cholesterol modulation of membrane fluidity and VIP receptor/effector system in rat prostatic epithelial cells

Regul Pept. 1991 May 17;33(3):287-97. doi: 10.1016/0167-0115(91)90231-5.

Abstract

Treatment of rat prostatic epithelial cells with cholesteryl hemisuccinate (ChH) resulted in a time- and dose-dependent inhibition of the stimulatory effect of the neuropeptide vasoactive intestinal peptide (VIP) on cyclic AMP accumulation, with a 40% decrease in the response to a maximally effective VIP concentration. Cell treatment with ChH led also to a similar blocking of isoproterenol (a beta-adrenergic agonist) action but did not modify forskolin (which is assumed to act directly on the catalytic unit of adenylate cyclase) activity upon cyclic AMP levels. The levels of the transduction protein Gs were similar in membranes from both control and ChH-treated cells as suggested by experiments on cholera toxin-catalyzed ADP-ribosylation. The inhibitory effect of ChH was accompanied by an increase of membrane microviscosity as estimated by measurements of fluorescence polarization. Experiments on VIP binding indicated that increasing cholesterol concentration in the plasma membrane led to a higher VIP binding capacity without changes in the affinity of VIP receptors. These data suggest that membrane cholesterol incorporation diminishes the coupling efficiency between adenylate cyclase and the VIP-receptor complex or other receptor systems (i.e., desensitization) due to an increase of plasma membrane rigidity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenylyl Cyclases / metabolism
  • Animals
  • Cell Membrane / metabolism
  • Cell Membrane / physiology
  • Cells, Cultured
  • Cholesterol / pharmacology*
  • Cholesterol Esters / pharmacology
  • Cyclic AMP / biosynthesis
  • Cyclic AMP / metabolism
  • Epithelium / metabolism
  • Epithelium / physiology
  • Epithelium / ultrastructure
  • Fluorescence Polarization
  • GTP-Binding Proteins / physiology
  • Male
  • Membrane Fluidity / drug effects*
  • Membrane Fluidity / physiology
  • Membrane Lipids / metabolism
  • Prostate / metabolism
  • Prostate / physiology*
  • Prostate / ultrastructure
  • Rats
  • Rats, Inbred Strains
  • Receptors, Gastrointestinal Hormone / drug effects
  • Receptors, Gastrointestinal Hormone / metabolism
  • Receptors, Gastrointestinal Hormone / physiology*
  • Receptors, Vasoactive Intestinal Peptide
  • Signal Transduction / drug effects
  • Signal Transduction / physiology
  • Vasoactive Intestinal Peptide / metabolism
  • Vasoactive Intestinal Peptide / pharmacology
  • Vasoactive Intestinal Peptide / physiology

Substances

  • Cholesterol Esters
  • Membrane Lipids
  • Receptors, Gastrointestinal Hormone
  • Receptors, Vasoactive Intestinal Peptide
  • Vasoactive Intestinal Peptide
  • Cholesterol
  • Cyclic AMP
  • GTP-Binding Proteins
  • Adenylyl Cyclases
  • cholesteryl succinate