Angiotensin II-induced stimulation of voltage-dependent Ca2+ currents in an adrenal cortical cell line

Item Type:	Article
Title:	Angiotensin II-induced stimulation of voltage-dependent Ca2+ currents in an adrenal cortical cell line
Creators Name:	Hescheler, J. and Rosenthal, W. and Hinsch, K.D. and Wulfern, M. and Trautwein, W. and Schultz, G.
Abstract:	Biochemical studies suggest that stimulation of aldosterone secretion by angiotensin II involves activation of voltage-dependent Ca2+ channels. We used an adrenocortical cell line (Y1) to study the effect of angiotensin II on transmembranous currents. The hormone (1 nM to 1 microM) caused depolarization of the plasma membrane (from -35 to 10 mV) and elicited repetitive action potentials. Using the whole-cell clamp technique, we identified two types of voltage-dependent Ca2+ currents which differed with respect to their threshold potential and time course of inactivation. Angiotensin II (1 nM to 1 microM) stimulated a slowly inactivating Ca2+ current on average up to 1.7-fold whereas a fast inactivating Ca2+ current remained almost unaffected by the hormone. Ca2+ currents were not influenced by forskolin (1 microM) or intracellularly applied cAMP (50 microM). Pretreatment of cells with pertussis toxin abolished the hormonal stimulation of the slowly inactivating Ca2+ current but was without effect on control currents. The toxin ADP-ribosylated a single membranous peptide of 40 kd Mr. An antiserum raised against a synthetic peptide corresponding to a region common to all sequenced alpha-subunits of guanine nucleotide-binding proteins (G-proteins) and an antiserum raised against a peptide corresponding to a region of alpha-subunits of Gi-like G-proteins reacted with membranous 40 kd peptides, whereas an antiserum raised against a synthetic peptide corresponding to a region specific for the alpha-subunit of the G-protein, G0, failed to recognize a peptide in the 39 to 40 kd region.
Keywords:	Y1 cells, Voltage-Dependent Ca2+ Currents, Pertussis Toxin, Guanine Nucleotide-Binding Proteins, Animals, Mice
Source:	EMBO Journal
ISSN:	0261-4189
Publisher:	Oxford University Press
Volume:	7
Number:	3
Page Range:	619-624
Date:	March 1988
Official Publication:	http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=454365&blobtype=pdf
PubMed:	View item in PubMed

Repository Staff Only: item control page