Preincubation with substance P induces substance P-stimulated phosphatidylinositol turnover in cultured cerebellar astrocytes

J Neurochem. 1992 Aug;59(2):443-8. doi: 10.1111/j.1471-4159.1992.tb09390.x.

Abstract

In this study we have investigated the effects of preincubation of cultured astrocytes with substance P (SP) on subsequent 125I-Bolton-Hunter conjugated SP (125I-BHSP) receptor binding, and SP-stimulated phosphatidyl-inositol (PI) accumulation. Spinal cord astrocytes preincubated for up to 96 h with SP (0.001-1,000 nM) suffered a dose-dependent decrease in both subsequent 125I-BHSP and SP-stimulated PI turnover. In contrast, preincubation of cerebellar astrocytes with SP resulted in an increase in SP-stimulated PI turnover, with no change in 125I-BHSP receptor binding. SP-induced PI turnover in cerebellar astrocytes was maximal after 72 h of preincubation with 0.1 nM SP. These data suggest that increased coupling between receptor and second messenger occurs in response to chronic exposure to SP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / cytology*
  • Astrocytes / metabolism*
  • Astrocytes / ultrastructure
  • Cells, Cultured
  • Cerebellum / cytology*
  • Cerebellum / metabolism
  • Cerebellum / ultrastructure
  • Dose-Response Relationship, Drug
  • Iodine Radioisotopes
  • Phosphatidylinositols / metabolism*
  • Rats
  • Receptors, Neurokinin-1
  • Receptors, Neurotransmitter / analysis
  • Receptors, Neurotransmitter / metabolism
  • Substance P / metabolism
  • Substance P / pharmacology*
  • Thymidine / metabolism
  • Time Factors
  • Tritium

Substances

  • Iodine Radioisotopes
  • Phosphatidylinositols
  • Receptors, Neurokinin-1
  • Receptors, Neurotransmitter
  • Tritium
  • Substance P
  • Thymidine