TY - JOUR
T1 - Spontaneous Intracellular Calcium Oscillations and Gsα Subunit Expression are Inversely Correlated with Secretory Granule Content in Pituitary Cells
AU - Chiavaroli, Carlo
AU - Cooper, Dermot M.F.
AU - Boyajian, Christine L.
AU - Murray‐Whelan, Rosemary
AU - Demaurex, Nicolas
AU - Spiegel, Allen M.
AU - Schlegel, Werner
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1992/8
Y1 - 1992/8
N2 - Cells of the pituitary tumour cell line GH4C1 were exposed to epidermal growth factor, estradiol and insulin for 5 days, a treatment which resulted in 1) increased prolactin storage in secretory granules, 2) the loss of spontaneous [Ca2+]1 oscillations, and 3) a selective reduction of the protein Gsα, seen in immunoblots, cholera toxin labelling, and vasoactive intestinal peptide stimulation of adenylyl cyclase. In contrast, the glucocorticoid dexamethasone, which increases the expression of Gsα, partially restored spontaneous [Ca2+]1 oscillations and decreased prolactin storage. It is concluded that Gsα levels in tumoral cells result in spontaneous electrical activity which may empty prolactin stores by the continuous activation of exocytosis.
AB - Cells of the pituitary tumour cell line GH4C1 were exposed to epidermal growth factor, estradiol and insulin for 5 days, a treatment which resulted in 1) increased prolactin storage in secretory granules, 2) the loss of spontaneous [Ca2+]1 oscillations, and 3) a selective reduction of the protein Gsα, seen in immunoblots, cholera toxin labelling, and vasoactive intestinal peptide stimulation of adenylyl cyclase. In contrast, the glucocorticoid dexamethasone, which increases the expression of Gsα, partially restored spontaneous [Ca2+]1 oscillations and decreased prolactin storage. It is concluded that Gsα levels in tumoral cells result in spontaneous electrical activity which may empty prolactin stores by the continuous activation of exocytosis.
KW - GHC cells
KW - G‐proteins
KW - [Ca]
KW - oscillations
KW - secretory granules
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U2 - 10.1111/j.1365-2826.1992.tb00195.x
DO - 10.1111/j.1365-2826.1992.tb00195.x
M3 - Article
AN - SCOPUS:0026726334
SN - 0953-8194
VL - 4
SP - 473
EP - 481
JO - Journal of Neuroendocrinology
JF - Journal of Neuroendocrinology
IS - 4
ER -