Work

Inositol trisphosphate and thapsigargin discriminate endoplasmic reticulum stores of calcium in rat brain

Year: 1990

Type: article

Abstract: ATP dependent Ca2+ accumulation into oxalate-loaded rat brain microsomes is potently inhibited by thapsigargin with an IC50 of 2 nM and maximal inhibition at 10 nM. Approximately 15% of the total A23187-releasable microsomal calcium store is insensitive to thapsigargin concentrations up to 100 microM. Inositol-1,4,5-trisphosphate (IP3) maximally inhibits 40% of the net Ca2+ accumulation by whole brain microsomes. Its effects are non-additive with thapsigargin suggesting that the IP3-sensitive Ca2+ pool is a subset of the thapsigargin sensitive Ca2+ pool. Marked regional differences occur in Ca2+ transport rates and sensitivity to both thapsigargin and IP3.

Source: Biochemical and Biophysical Research Communications

DOI: 10.1016/0006-291x(90)90747-b

Authors: Ajay Verma, David J. Hirsch, Michael R. Hanley, Ole Thastrup, S.Brogger Christensen, Solomon H. Snyder