Abstract
Serotonin activates chloride currents in Xenopus oocytes injected with a subfraction of rat brain poly(A)+ mRNA. Patch-clamp recordings from cell-attached patches showed that serotonin, applied locally outside the patch, caused the opening of channels of approximately equal to 3 pS conductance and an average lifetime of approximately equal to 100 msec. The extrapolated reversal potential indicated that the channels are chloride-selective. Single-channel currents with similar characteristics were observed in inside-out patches from native oocytes in response to elevated calcium concentrations on the cytoplasmic side. Measurements of intracellular calcium concentration ([Ca2+]i) by fura-2 fluorescence showed approximately equal to 10-fold increases in [Ca2+]i in response to serotonin application in both normal and calcium-free Ringer solution in mRNA-injected oocytes. Little or no response to serotonin was observed in native oocytes. These results suggest that serotonin activation of receptors that are inserted into the oocyte membrane following injection of rat brain poly(A)+ mRNA can induce calcium release from intracellular stores. The increase in [Ca2+]i subsequently activates calcium-dependent chloride channels. Because calcium-dependent chloride channels and a receptor-controlled mechanism of internal calcium release have been shown to exist in native oocytes, we conclude that the newly inserted serotonin receptors utilized the endogenous second-messenger-mediated calcium release to activate endogenous calcium-dependent chloride channels.
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- Almers W., Neher E. The Ca signal from fura-2 loaded mast cells depends strongly on the method of dye-loading. FEBS Lett. 1985 Nov 11;192(1):13–18. doi: 10.1016/0014-5793(85)80033-8. [DOI] [PubMed] [Google Scholar]
- Aviv H., Leder P. Purification of biologically active globin messenger RNA by chromatography on oligothymidylic acid-cellulose. Proc Natl Acad Sci U S A. 1972 Jun;69(6):1408–1412. doi: 10.1073/pnas.69.6.1408. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barbaccia M. L., Brunello N., Chuang D. M., Costa E. Serotonin-elicited amplification of adenylate cyclase activity in hippocampal membranes from adult rat. J Neurochem. 1983 Jun;40(6):1671–1679. doi: 10.1111/j.1471-4159.1983.tb08141.x. [DOI] [PubMed] [Google Scholar]
- Barish M. E. A transient calcium-dependent chloride current in the immature Xenopus oocyte. J Physiol. 1983 Sep;342:309–325. doi: 10.1113/jphysiol.1983.sp014852. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Busa W. B., Ferguson J. E., Joseph S. K., Williamson J. R., Nuccitelli R. Activation of frog (Xenopus laevis) eggs by inositol trisphosphate. I. Characterization of Ca2+ release from intracellular stores. J Cell Biol. 1985 Aug;101(2):677–682. doi: 10.1083/jcb.101.2.677. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Conn P. J., Sanders-Bush E. Selective 5HT-2 antagonists inhibit serotonin stimulated phosphatidylinositol metabolism in cerebral cortex. Neuropharmacology. 1984 Aug;23(8):993–996. doi: 10.1016/0028-3908(84)90017-0. [DOI] [PubMed] [Google Scholar]
- Gerschenfeld H. M., Paupardin-Tritsch D. Ionic mechanisms and receptor properties underlying the responses of molluscan neurones to 5-hydroxytryptamine. J Physiol. 1974 Dec;243(2):427–456. doi: 10.1113/jphysiol.1974.sp010761. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Glisin V., Crkvenjakov R., Byus C. Ribonucleic acid isolated by cesium chloride centrifugation. Biochemistry. 1974 Jun 4;13(12):2633–2637. doi: 10.1021/bi00709a025. [DOI] [PubMed] [Google Scholar]
- 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]
- Gundersen C. B., Miledi R., Parker I. Glutamate and kainate receptors induced by rat brain messenger RNA in Xenopus oocytes. Proc R Soc Lond B Biol Sci. 1984 Apr 24;221(1223):127–143. doi: 10.1098/rspb.1984.0027. [DOI] [PubMed] [Google Scholar]
- Gundersen C. B., Miledi R., Parker I. Messenger RNA from human brain induces drug- and voltage-operated channels in Xenopus oocytes. 1984 Mar 29-Apr 4Nature. 308(5958):421–424. doi: 10.1038/308421a0. [DOI] [PubMed] [Google Scholar]
- Gundersen C. B., Miledi R., Parker I. Serotonin receptors induced by exogenous messenger RNA in Xenopus oocytes. Proc R Soc Lond B Biol Sci. 1983 Aug 22;219(1214):103–109. doi: 10.1098/rspb.1983.0062. [DOI] [PubMed] [Google Scholar]
- Kusano K., Miledi R., Stinnakre J. Cholinergic and catecholaminergic receptors in the Xenopus oocyte membrane. J Physiol. 1982 Jul;328:143–170. doi: 10.1113/jphysiol.1982.sp014257. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marty A., Tan Y. P., Trautmann A. Three types of calcium-dependent channel in rat lacrimal glands. J Physiol. 1984 Dec;357:293–325. doi: 10.1113/jphysiol.1984.sp015501. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Methfessel C., Witzemann V., Takahashi T., Mishina M., Numa S., Sakmann B. Patch clamp measurements on Xenopus laevis oocytes: currents through endogenous channels and implanted acetylcholine receptor and sodium channels. Pflugers Arch. 1986 Dec;407(6):577–588. doi: 10.1007/BF00582635. [DOI] [PubMed] [Google Scholar]
- Miledi R., Parker I. Chloride current induced by injection of calcium into Xenopus oocytes. J Physiol. 1984 Dec;357:173–183. doi: 10.1113/jphysiol.1984.sp015495. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mishina M., Takai T., Imoto K., Noda M., Takahashi T., Numa S., Methfessel C., Sakmann B. Molecular distinction between fetal and adult forms of muscle acetylcholine receptor. Nature. 1986 May 22;321(6068):406–411. doi: 10.1038/321406a0. [DOI] [PubMed] [Google Scholar]
- Neher E., Almers W. Fast calcium transients in rat peritoneal mast cells are not sufficient to trigger exocytosis. EMBO J. 1986 Jan;5(1):51–53. doi: 10.1002/j.1460-2075.1986.tb04176.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Oron Y., Dascal N., Nadler E., Lupu M. Inositol 1,4,5-trisphosphate mimics muscarinic response in Xenopus oocytes. Nature. 1985 Jan 10;313(5998):141–143. doi: 10.1038/313141a0. [DOI] [PubMed] [Google Scholar]
- Parker I., Gundersen C. B., Miledi R. Intracellular Ca2+-dependent and Ca2+-independent responses of rat brain serotonin receptors transplanted to Xenopus oocytes. Neurosci Res. 1985 Aug;2(6):491–496. doi: 10.1016/0168-0102(85)90021-5. [DOI] [PubMed] [Google Scholar]
- Parker I., Miledi R. Changes in intracellular calcium and in membrane currents evoked by injection of inositol trisphosphate into Xenopus oocytes. Proc R Soc Lond B Biol Sci. 1986 Aug 22;228(1252):307–315. doi: 10.1098/rspb.1986.0057. [DOI] [PubMed] [Google Scholar]
- Shuster M. J., Camardo J. S., Siegelbaum S. A., Kandel E. R. Cyclic AMP-dependent protein kinase closes the serotonin-sensitive K+ channels of Aplysia sensory neurones in cell-free membrane patches. 1985 Jan 31-Feb 6Nature. 313(6001):392–395. doi: 10.1038/313392a0. [DOI] [PubMed] [Google Scholar]