Cacicedo L, Tolón R M, Lorenzo M J, López J, Sánchez Franco F
Servicio de Endocrinologia, Hospital Ramón y Cajal, Madrid, Spain.
J Pediatr Endocrinol. 1993 Jul-Dec;6(3-4):219-23. doi: 10.1515/jpem.1993.6.3-4.219.
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.
分析了钾离子去极化对胎儿脑皮质细胞原代培养物中生长抑素mRNA（SS mRNA）水平的刺激作用。去极化刺激，如56 mM K⁺浓度作用24小时，可引起培养基中免疫反应性生长抑素（IR-SS）释放增加以及SS mRNA水平升高，这表明生长抑素分泌可能与SS mRNA积累相关。这些变化被钙离子通道拮抗剂维拉帕米（VPM）抑制。相比之下，河豚毒素（TTX）阻断钠离子通道并未改变钾离子诱导的24小时SS mRNA增加。这些结果表明，钾离子诱导SS mRNA表达涉及钙离子通道的调节。
