Intracellular Angiotensin II Inhibits Heterologous Receptor Stimulated Ca²⁺ Entry

Creator(s)

Catalin M. Filipeanu, University of Groningen, University Medical Center Groningen, Groningen University Institute for Drug Exploration (GUIDE)
Eugen Brailoiu, University of Groningen, University Medical Center Groningen, Groningen University Institute for Drug Exploration (GUIDE)
Robert H. Henning, University of Groningen, University Medical Center Groningen, Groningen University Institute for Drug Exploration (GUIDE)
Leo E. Deelman, University of Groningen, University Medical Center Groningen, Groningen University Institute for Drug Exploration (GUIDE)
Dick De Zeeuw, University of Groningen, University Medical Center Groningen, Groningen University Institute for Drug Exploration (GUIDE)
S. Adriaan Nelemans, University of Groningen, University Medical Center Groningen, Groningen University Institute for Drug Exploration (GUIDE)

Document Type

Article

Publication Date

11-30-2001

Description

Recent studies show that angiotensin II (AngII) can act from within the cell, possibly via intracellular receptors pharmacologically different from typical plasma membrane AngII receptors. The role of this intracellular AngII (AngIIi) is unclear. Besides direct effects of AngIIi on cellular processes one could hypothesise a possible role of AngIIi in modulation of cellular responses induced after heterologous receptor stimulation. We therefore examined if AngIIi influences [Ca2+]i in A7r5 smooth muscle cells after serotonin (5HT) or UTP receptor stimulation. Application of AngIIi using liposomes, markedly inhibited 45Ca2+ influx after receptor stimulation with 5HT or UTP. This inhibition was reversible by intracellular administration of the AT1-antagonist losartan and not influenced by the AT2-antagonist PD123319. Similar results were obtained in single cell [Ca2+]i measurements, showing that AngIIi predominantly influences Ca2+ influx and not Ca2+ release via AT1-like receptors. It is concluded that AngIIi modulates signal transduction activated by heterologous receptor stimulation.

Citation Information

Filipeanu, Catalin M.; Brailoiu, Eugen; Henning, Robert H.; Deelman, Leo E.; De Zeeuw, Dick; and Nelemans, S. Adriaan. 2001. Intracellular Angiotensin II Inhibits Heterologous Receptor Stimulated Ca²⁺ Entry. Life Sciences. Vol.70(2). 171-180. https://doi.org/10.1016/S0024-3205(01)01389-3 PMID: 11787942 ISSN: 0024-3205