Document Detail


Regulation of ionic currents in pheochromocytoma cells by nerve growth factor and dexamethasone.
MedLine Citation:
PMID:  2479727     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Growth factors and hormones induce differentiation of clonal pheochromocytoma (PC12) cells, which are derived from rat adrenal medulla chromaffin cells. On application of nerve growth factor (NGF), PC12 cells extend neurites and express properties characteristic of autonomic ganglion cells. In contrast, incubation of PC12 cells with a corticosteroid, dexamethasone (DEX), does not induce neurite formation but causes an increase in tyrosine hydroxylase activity, suggesting that the cells become chromaffin cell-like. The ability of NGF and DEX to regulate ionic currents has been less well studied. Therefore, we examined how long-term NGF and DEX treatments affected voltage-dependent Na, Ca, and K currents in PC12 cells. Voltage-dependent Na currents were observed only in a small fraction of the PC12 cells in the absence of NGF or DEX. Virtually all NGF-treated cells expressed Na currents within 7 d. DEX increased the number of cells expressing voltage-dependent Na current slowly over 3 weeks, but, unlike NGF, DEX did not change Na current density. Both NGF and DEX also affected the expression of voltage-dependent Ca currents. Most of the untreated cells had only sustained, high-threshold voltage-dependent Ca currents. Chronic application of NGF or DEX increased the fractions of the cells that showed transient, low-threshold T-type Ca currents in addition to the high-threshold currents. The T-type Ca current density, however, increased significantly only in NGF-treated cells. Neither DEX nor NGF affected the voltage-dependent K currents. These results suggest that the expression of voltage-dependent Na and Ca currents are differentially regulated by NGF and DEX. The distinction between treated and untreated cells decreased after 3 weeks in culture as older untreated cells showed increases in the fraction of cells expressing both Na and low-threshold Ca currents. A PC12 subline selected for adherence to uncoated plastic also showed increased fraction of cells expressing these currents, suggesting that interactions with substrate may also influence ionic current expression.
Authors:
S S Garber; T Hoshi; R W Aldrich
Related Documents :
20400727 - A comparison of high-content screening versus manual analysis to assay the effects of m...
9477317 - The leech receptor protein tyrosine phosphatase hmlar2 is concentrated in growth cones ...
19577197 - Directional migration of neuronal pc12 cells in a ratchet wheel shaped microchamber.
10777547 - Simultaneous suppression of cdc2 and cdk2 activities induces neuronal differentiation o...
7026037 - Localization of relaxin in human gestational corpus luteum.
21461557 - Multiplexed profiling of secreted proteins for the detection of potential space biomark...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of neuroscience : the official journal of the Society for Neuroscience     Volume:  9     ISSN:  0270-6474     ISO Abbreviation:  J. Neurosci.     Publication Date:  1989 Nov 
Date Detail:
Created Date:  1990-01-03     Completed Date:  1990-01-03     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  8102140     Medline TA:  J Neurosci     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  3976-87     Citation Subset:  IM    
Affiliation:
Department of Neurobiology, Stanford University, California 94305.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adrenal Gland Neoplasms / physiopathology*
Animals
Calcium Channels / drug effects,  physiology
Cell Line
Clone Cells
Dexamethasone / pharmacology*
Electrophysiology / methods
Ion Channels / drug effects,  physiology*
Nerve Growth Factors / pharmacology*
Pheochromocytoma / physiopathology*
Potassium Channels / drug effects,  physiology
Rats
Sodium Channels / drug effects,  physiology
Tumor Cells, Cultured / drug effects,  physiology
Grant Support
ID/Acronym/Agency:
NS07158/NS/NINDS NIH HHS; NS23294/NS/NINDS NIH HHS
Chemical
Reg. No./Substance:
0/Calcium Channels; 0/Ion Channels; 0/Nerve Growth Factors; 0/Potassium Channels; 0/Sodium Channels; 50-02-2/Dexamethasone

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Sexual maturity-dependent changes in neuronal morphology in the prepacemaker nucleus of adult weakly...
Next Document:  Regenerated retinal ganglion cell axons can form well-differentiated synapses in the superior collic...