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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1991 Nov 15;88(22):10262–10266. doi: 10.1073/pnas.88.22.10262

Thyrotropin-releasing hormone induces opposite effects on Ca2+ channel currents in pituitary cells by two pathways.

M Gollasch 1, H Haller 1, G Schultz 1, J Hescheler 1
PMCID: PMC52908  PMID: 1719553

Abstract

Thyrotropin-releasing hormone (TRH) stimulates pituitary secretion by steps involving a cytosolic Ca2+ rise. We examined various pathways of Ca2+ elevation in pituitary GH3 cells. By using the patch clamp technique in the whole-cell configuration and Ba2+ as divalent charge carrier through Ca2+ channels, TRH (1 microM) reversibly reduced the current by about 55%. This hormonal effect was prevented by infusing guanine 5'-[beta-thio]diphosphate (GDP[beta S]) intracellularly but not by pretreating the cell with pertussis toxin (PT). Since PT-insensitive guanine nucleotide-binding regulatory (G) proteins are known to mediate a hormone-stimulated inositol trisphosphate-mediated Ca2+ release from intracellular stores, we assume that the inhibitory effect of TRH on Ba2+ currents through Ca2+ channels is caused by the increased intracellular Ca2+. To prevent a Ca(2+)-release-dependent inhibition of Ca2+ channels, we preincubated GH3 cells in a medium free of divalent charge carriers and measured the Na+ current through Ca2+ channels. When fura-2 was used as indicator for the cytosolic Ca2+, TRH induced a release from intracellular stores only once and had no effect on the intracellular Ca2+ concentration during further applications. In line with this observation, TRH initially reduced the Na+ current through Ca2+ channels but stimulated it during subsequent applications. The stimulation was sensitive to GDP[beta S] and was abolished by pretreatment with PT, suggesting that the stimulatory action of TRH is mediated by a G protein different from the one that functionally couples the receptor to phosphatidylinositol 4,5-bisphosphate hydrolysis. In conclusion, the present data suggest that TRH increases the intracellular Ca2+ concentration by two interacting pathways, that release from intracellular stores causes a secondary blockage of Ca2+ channels, and that, especially with empty intracellular Ca2+ stores, Ca2+ channels are stimulated by a PT-sensitive G protein.

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Selected References

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  1. Aub D. L., Frey E. A., Sekura R. D., Cote T. E. Coupling of the thyrotropin-releasing hormone receptor to phospholipase C by a GTP-binding protein distinct from the inhibitory or stimulatory GTP-binding protein. J Biol Chem. 1986 Jul 15;261(20):9333–9340. [PubMed] [Google Scholar]
  2. Bauer C. K., Meyerhof W., Schwarz J. R. An inward-rectifying K+ current in clonal rat pituitary cells and its modulation by thyrotrophin-releasing hormone. J Physiol. 1990 Oct;429:169–189. doi: 10.1113/jphysiol.1990.sp018250. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bean B. P. Classes of calcium channels in vertebrate cells. Annu Rev Physiol. 1989;51:367–384. doi: 10.1146/annurev.ph.51.030189.002055. [DOI] [PubMed] [Google Scholar]
  4. Bean B. P. Neurotransmitter inhibition of neuronal calcium currents by changes in channel voltage dependence. Nature. 1989 Jul 13;340(6229):153–156. doi: 10.1038/340153a0. [DOI] [PubMed] [Google Scholar]
  5. Belles B., Malécot C. O., Hescheler J., Trautwein W. "Run-down" of the Ca current during long whole-cell recordings in guinea pig heart cells: role of phosphorylation and intracellular calcium. Pflugers Arch. 1988 Apr;411(4):353–360. doi: 10.1007/BF00587713. [DOI] [PubMed] [Google Scholar]
  6. Birnbaumer L., Abramowitz J., Brown A. M. Receptor-effector coupling by G proteins. Biochim Biophys Acta. 1990 May 7;1031(2):163–224. doi: 10.1016/0304-4157(90)90007-y. [DOI] [PubMed] [Google Scholar]
  7. Bleakman D., Brorson J. R., Miller R. J. The effect of capsaicin on voltage-gated calcium currents and calcium signals in cultured dorsal root ganglion cells. Br J Pharmacol. 1990 Oct;101(2):423–431. doi: 10.1111/j.1476-5381.1990.tb12725.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Brostrom C. O., Brostrom M. A. Calcium-dependent regulation of protein synthesis in intact mammalian cells. Annu Rev Physiol. 1990;52:577–590. doi: 10.1146/annurev.ph.52.030190.003045. [DOI] [PubMed] [Google Scholar]
  9. Charbonneau M., Grey R. D. The onset of activation responsiveness during maturation coincides with the formation of the cortical endoplasmic reticulum in oocytes of Xenopus laevis. Dev Biol. 1984 Mar;102(1):90–97. doi: 10.1016/0012-1606(84)90177-5. [DOI] [PubMed] [Google Scholar]
  10. Cohen C. J., McCarthy R. T., Barrett P. Q., Rasmussen H. Ca channels in adrenal glomerulosa cells: K+ and angiotensin II increase T-type Ca channel current. Proc Natl Acad Sci U S A. 1988 Apr;85(7):2412–2416. doi: 10.1073/pnas.85.7.2412. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Davidson J. S., Wakefield I. K., King J. A., Mulligan G. P., Millar R. P. Dual pathways of calcium entry in spike and plateau phases of luteinizing hormone release from chicken pituitary cells: sequential activation of receptor-operated and voltage-sensitive calcium channels by gonadotropin-releasing hormone. Mol Endocrinol. 1988 Apr;2(4):382–390. doi: 10.1210/mend-2-4-382. [DOI] [PubMed] [Google Scholar]
  12. Dubinsky J. M., Oxford G. S. Dual modulation of K channels by thyrotropin-releasing hormone in clonal pituitary cells. Proc Natl Acad Sci U S A. 1985 Jun;82(12):4282–4286. doi: 10.1073/pnas.82.12.4282. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Fenwick E. M., Marty A., Neher E. Sodium and calcium channels in bovine chromaffin cells. J Physiol. 1982 Oct;331:599–635. doi: 10.1113/jphysiol.1982.sp014394. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gershengorn M. C., Geras E., Purrello V. S., Rebecchi M. J. Inositol trisphosphate mediates thyrotropin-releasing hormone mobilization of nonmitochondrial calcium in rat mammotropic pituitary cells. J Biol Chem. 1984 Sep 10;259(17):10675–10681. [PubMed] [Google Scholar]
  15. Grynkiewicz G., Poenie M., Tsien R. Y. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem. 1985 Mar 25;260(6):3440–3450. [PubMed] [Google Scholar]
  16. Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
  17. Hescheler J., Rosenthal W., Hinsch K. D., Wulfern M., Trautwein W., Schultz G. Angiotensin II-induced stimulation of voltage-dependent Ca2+ currents in an adrenal cortical cell line. EMBO J. 1988 Mar;7(3):619–624. doi: 10.1002/j.1460-2075.1988.tb02855.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Hess P., Lansman J. B., Tsien R. W. Calcium channel selectivity for divalent and monovalent cations. Voltage and concentration dependence of single channel current in ventricular heart cells. J Gen Physiol. 1986 Sep;88(3):293–319. doi: 10.1085/jgp.88.3.293. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Hess P., Lansman J. B., Tsien R. W. Different modes of Ca channel gating behaviour favoured by dihydropyridine Ca agonists and antagonists. Nature. 1984 Oct 11;311(5986):538–544. doi: 10.1038/311538a0. [DOI] [PubMed] [Google Scholar]
  20. Ingram C. D., Bicknell R. J., Mason W. T. Intracellular recordings from bovine anterior pituitary cells: modulation of spontaneous activity by regulators of prolactin secretion. Endocrinology. 1986 Dec;119(6):2508–2518. doi: 10.1210/endo-119-6-2508. [DOI] [PubMed] [Google Scholar]
  21. Kalman D., O'Lague P. H., Erxleben C., Armstrong D. L. Calcium-dependent inactivation of the dihydropyridine-sensitive calcium channels in GH3 cells. J Gen Physiol. 1988 Oct;92(4):531–548. doi: 10.1085/jgp.92.4.531. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Kokubun S., Irisawa H. Effects of various intracellular Ca ion concentrations on the calcium current of guinea-pig single ventricular cells. Jpn J Physiol. 1984;34(4):599–611. doi: 10.2170/jjphysiol.34.599. [DOI] [PubMed] [Google Scholar]
  23. Korbmacher C., Helbig H., Haller H., Erickson-Lamy K. A., Wiederholt M. Endothelin depolarizes membrane voltage and increases intracellular calcium concentration in human ciliary muscle cells. Biochem Biophys Res Commun. 1989 Nov 15;164(3):1031–1039. doi: 10.1016/0006-291x(89)91773-7. [DOI] [PubMed] [Google Scholar]
  24. Kuan S. I., Login I. S., Judd A. M., MacLeod R. M. A comparison of the concentration-dependent actions of thyrotropin-releasing hormone, angiotensin II, bradykinin, and Lys-bradykinin on cytosolic free calcium dynamics in rat anterior pituitary cells: selective effects of dopamine. Endocrinology. 1990 Oct;127(4):1841–1848. doi: 10.1210/endo-127-4-1841. [DOI] [PubMed] [Google Scholar]
  25. Levitan E. S., Kramer R. H. Neuropeptide modulation of single calcium and potassium channels detected with a new patch clamp configuration. Nature. 1990 Dec 6;348(6301):545–547. doi: 10.1038/348545a0. [DOI] [PubMed] [Google Scholar]
  26. Lux H. D., Carbone E., Zucker H. Na+ currents through low-voltage-activated Ca2+ channels of chick sensory neurones: block by external Ca2+ and Mg2+. J Physiol. 1990 Nov;430:159–188. doi: 10.1113/jphysiol.1990.sp018287. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Marty A., Neher E. Potassium channels in cultured bovine adrenal chromaffin cells. J Physiol. 1985 Oct;367:117–141. doi: 10.1113/jphysiol.1985.sp015817. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Mollard P., Vacher P., Dufy B., Winiger B. P., Schlegel W. Thyrotropin-releasing hormone-induced rise in cytosolic calcium and activation of outward K+ current monitored simultaneously in individual GH3B6 pituitary cells. J Biol Chem. 1988 Dec 25;263(36):19570–19576. [PubMed] [Google Scholar]
  29. Morad M., Davies N. W., Kaplan J. H., Lux H. D. Inactivation and block of calcium channels by photo-released Ca2+ in dorsal root ganglion neurons. Science. 1988 Aug 12;241(4867):842–844. doi: 10.1126/science.2457253. [DOI] [PubMed] [Google Scholar]
  30. Muallem S., Fimmel C. J., Pandol S. J., Sachs G. Regulation of free cytosolic Ca2+ in the peptic and parietal cells of the rabbit gastric gland. J Biol Chem. 1986 Feb 25;261(6):2660–2667. [PubMed] [Google Scholar]
  31. Naor Z., Capponi A. M., Rossier M. F., Ayalon D., Limor R. Gonadotropin-releasing hormone-induced rise in cytosolic free Ca2+ levels: mobilization of cellular and extracellular Ca2+ pools and relationship to gonadotropin secretion. Mol Endocrinol. 1988 Jun;2(6):512–520. doi: 10.1210/mend-2-6-512. [DOI] [PubMed] [Google Scholar]
  32. Offermanns S., Schultz G., Rosenthal W. Secretion-stimulating and secretion-inhibiting hormones stimulate high-affinity pertussis-toxin-sensitive GTPases in membranes of a pituitary cell line. Eur J Biochem. 1989 Mar 15;180(2):283–287. doi: 10.1111/j.1432-1033.1989.tb14645.x. [DOI] [PubMed] [Google Scholar]
  33. Plant T. D., Standen N. B., Ward T. A. The effects of injection of calcium ions and calcium chelators on calcium channel inactivation in Helix neurones. J Physiol. 1983 Jan;334:189–212. doi: 10.1113/jphysiol.1983.sp014489. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Putney J. W., Jr A model for receptor-regulated calcium entry. Cell Calcium. 1986 Feb;7(1):1–12. doi: 10.1016/0143-4160(86)90026-6. [DOI] [PubMed] [Google Scholar]
  35. Rebecchi M. J., Gershengorn M. C. Thyroliberin stimulates rapid hydrolysis of phosphatidylinositol 4,5-bisphosphate by a phosphodiesterase in rat mammotropic pituitary cells. Evidence for an early Ca2+-independent action. Biochem J. 1983 Nov 15;216(2):287–294. doi: 10.1042/bj2160287. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Ritchie A. K. Thyrotropin-releasing hormone stimulates a calcium-activated potassium current in a rat anterior pituitary cell line. J Physiol. 1987 Apr;385:611–625. doi: 10.1113/jphysiol.1987.sp016510. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Rosenthal W., Hescheler J., Hinsch K. D., Spicher K., Trautwein W., Schultz G. Cyclic AMP-independent, dual regulation of voltage-dependent Ca2+ currents by LHRH and somatostatin in a pituitary cell line. EMBO J. 1988 Jun;7(6):1627–1633. doi: 10.1002/j.1460-2075.1988.tb02989.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Rousseau E., Meissner G. Single cardiac sarcoplasmic reticulum Ca2+-release channel: activation by caffeine. Am J Physiol. 1989 Feb;256(2 Pt 2):H328–H333. doi: 10.1152/ajpheart.1989.256.2.H328. [DOI] [PubMed] [Google Scholar]
  39. Sakakibara M., Alkon D. L., DeLorenzo R., Goldenring J. R., Neary J. T., Heldman E. Modulation of calcium-mediated inactivation of ionic currents by Ca2+/calmodulin-dependent protein kinase II. Biophys J. 1986 Aug;50(2):319–327. doi: 10.1016/S0006-3495(86)83465-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Sartor P., Dufy-Barbe L., Corcuff J. B., Taupignon A., Dufy B. Electrophysiological response to thyrotropin-releasing hormone of rat lactotrophs in primary culture. Am J Physiol. 1990 Feb;258(2 Pt 1):E311–E319. doi: 10.1152/ajpendo.1990.258.2.E311. [DOI] [PubMed] [Google Scholar]
  41. Schlegel W., Roduit C., Zahnd G. R. Polyphosphoinositide hydrolysis by phospholipase C is accelerated by thyrotropin releasing hormone (TRH) in clonal rat pituitary cells (GH3 cells). FEBS Lett. 1984 Mar 12;168(1):54–60. doi: 10.1016/0014-5793(84)80205-7. [DOI] [PubMed] [Google Scholar]
  42. Schlegel W., Winiger B. P., Mollard P., Vacher P., Wuarin F., Zahnd G. R., Wollheim C. B., Dufy B. Oscillations of cytosolic Ca2+ in pituitary cells due to action potentials. Nature. 1987 Oct 22;329(6141):719–721. doi: 10.1038/329719a0. [DOI] [PubMed] [Google Scholar]
  43. Schlegel W., Wuarin F., Zbaren C., Wollheim C. B., Zahnd G. R. Pertussis toxin selectively abolishes hormone induced lowering of cytosolic calcium in GH3 cells. FEBS Lett. 1985 Sep 9;189(1):27–32. doi: 10.1016/0014-5793(85)80835-8. [DOI] [PubMed] [Google Scholar]
  44. Stojilković S. S., Iida T., Virmani M. A., Izumi S., Rojas E., Catt K. J. Dependence of hormone secretion on activation-inactivation kinetics of voltage-sensitive Ca2+ channels in pituitary gonadotrophs. Proc Natl Acad Sci U S A. 1990 Nov;87(22):8855–8859. doi: 10.1073/pnas.87.22.8855. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Streb H., Irvine R. F., Berridge M. J., Schulz I. Release of Ca2+ from a nonmitochondrial intracellular store in pancreatic acinar cells by inositol-1,4,5-trisphosphate. Nature. 1983 Nov 3;306(5938):67–69. doi: 10.1038/306067a0. [DOI] [PubMed] [Google Scholar]
  46. Suarez-Kurtz G., Katz G. M., Reuben J. P. Currents carried by sodium ions through transient calcium channels in clonal GH3 pituitary cells. Pflugers Arch. 1987 Oct;410(3):345–347. doi: 10.1007/BF00580289. [DOI] [PubMed] [Google Scholar]
  47. Tan K. N., Tashjian A. H., Jr Receptor-mediated release of plasma membrane-associated calcium and stimulation of calcium uptake by thyrotropin-releasing hormone in pituitary cells in culture. J Biol Chem. 1981 Sep 10;256(17):8994–9002. [PubMed] [Google Scholar]
  48. Tan K. N., Tashjian A. H., Jr Voltage-dependent calcium channels in pituitary cells in culture. II. Participation in thyrotropin-releasing hormone action on prolactin release. J Biol Chem. 1984 Jan 10;259(1):427–434. [PubMed] [Google Scholar]
  49. Winiger B. P., Schlegel W. Rapid transient elevations of cytosolic calcium triggered by thyrotropin releasing hormone in individual cells of the pituitary line GH3B6. Biochem J. 1988 Oct 1;255(1):161–167. doi: 10.1042/bj2550161. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Wojcikiewicz R. J., Kent P. A., Fain J. N. Evidence that thyrotropin-releasing hormone-induced increases in GTPase activity and phosphoinositide metabolism in GH3 cells are mediated by a guanine nucleotide-binding protein other than Gs or Gi. Biochem Biophys Res Commun. 1986 Aug 14;138(3):1383–1389. doi: 10.1016/s0006-291x(86)80436-3. [DOI] [PubMed] [Google Scholar]
  51. Yamashita N., Takuwa Y., Ogata E. Growth hormone-releasing factor reduces voltage-gated Ca2+ channel current in rat GH3 cells. J Membr Biol. 1985;87(3):241–247. doi: 10.1007/BF01871224. [DOI] [PubMed] [Google Scholar]

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