title: Potassium-induced depolarization stimulates somatostatin gene expression in cultured fetal rat cerebrocortical cells.
abstract: The stimulatory effect of potassium depolarization upon somatostatin mRNA (SS mRNA) levels in primary cultures of fetal cerebrocortical cells was analyzed. Depolarizing stimuli, such as 56 mM K+ concentration for 24 hours, elicited an increase in immunoreactive somatostatin (IR-SS) release to the media and SS mRNA levels, suggesting that somatostatin secretion can be coupled to SS mRNA accumulation. These changes were inhibited by the Ca2+ channel antagonist verapamil (VPM). In contrast, Na+ channel blockade by tetrodotoxin (TTX) did not modify the 24 h potassium-induced increase in SS mRNA. These results suggest that the induction of SS mRNA expression by K+ involves the modulation of calcium ion channels.
authors.affiliation: Servicio de Endocrinologia, Hospital Ramón y Cajal, Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Cacicedo
authors.forename: R M
authors.initials: RM
authors.lastname: Tolón
authors.forename: M J
authors.initials: MJ
authors.lastname: Lorenzo
authors.forename: J
authors.initials: J
authors.lastname: López
authors.forename: F
authors.initials: F
authors.lastname: Sánchez Franco
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000196:embryology*; D004594:Electrophysiology; D005333:Fetus / Q000166:cytology / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects*; D011188:Potassium / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013004:Somatostatin / Q000235:genetics* / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D013004:Somatostatin; D011188:Potassium