title: 17beta-estradiol rapidly mobilizes intracellular calcium from ryanodine-receptor-gated stores via a PKC-PKA-Erk-dependent pathway in the human eccrine sweat gland cell line NCL-SG3.
abstract: We describe a novel rapid non-genomic effect of 17beta-estradiol (E2) on intracellular Ca2+ ([Ca2+]i) signalling in the eccrine sweat gland epithelial cell line NCL-SG3. E2 had no observable effect on basal [Ca2+]i, however exposure of cells to E2 in the presence of the microsomal Ca2+ ATPase pump inhibitor, thapsigargin, produced a secondary, sustained increase in [Ca2+]i compared to thapsigargin treatment alone, where cells responded with a transient single spike-like increase in [Ca2+]i. The E2-induced increase in [Ca2+]i was not dependent on the presence of extracellular calcium and was completely abolished by ryanodine (100 microM). The estrogen receptor antagonist ICI 182,780 (1 microM) prevented the E2-induced effects suggesting a role for the estrogen receptor in the release of [Ca2+]i from ryanodine-receptor-gated stores. The E2-induced effect on [Ca2+]i could also be prevented by the protein kinase C delta (PKCdelta)-specific inhibitor rottlerin (10 microM), the protein kinase A (PKA) inhibitor Rp-adenosine 3',5'-cyclic monophosphorothioate (200 microM) and the MEK inhibitor PD98059 (10 microM). We established E2 rapidly activates the novel PKC isoform PKCepsilon, PKA and Erk 1/2 MAPK in a PKCdelta and estrogen-receptor-dependent manner. The E2-induced effect was specific to 17beta-estradiol, as other steroids had no effect on [Ca2+]i. We have demonstrated a novel mechanism by which E2 rapidly modulates [Ca2+]i release from ryanodine-receptor-gated intracellular Ca2+ stores. The signal transduction pathway involves the estrogen receptor coupled to a PKC-PKA-Erk 1/2 signalling pathway.
authors.affiliation: Molecular Medicine Laboratories, Royal College of Surgeons in Ireland, RCSI Education and Research Centre, Smurfit Building, Beaumont Hospital, P.O. Box 9063, Dublin 9, Ireland. rmuchekehu@ucsd.edu
authors.forename: Ruth W
authors.initials: RW
authors.lastname: Muchekehu
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Harvey
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004439:Eccrine Glands / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology*; D004967:Estrogens / Q000494:pharmacology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D011493:Protein Kinase C / Q000378:metabolism*; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism*; D015398:Signal Transduction; D019284:Thapsigargin / Q000494:pharmacology; D013997:Time Factors
chemical_list: D004967:Estrogens; D019837:Ryanodine Receptor Calcium Release Channel; D004958:Estradiol; D019284:Thapsigargin; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D048049:Extracellular Signal-Regulated MAP Kinases; D002118:Calcium