Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland

Mean Hwan Kim, Shunsuke Uehara, Akiko Muroyama, Bertil Hille, Yoshinori Moriyama, Duk Su Koh

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Glutamate transporters are expressed throughout the CNS where their major role is to clear released glutamate from presynaptic terminals. Here, we report a novel function of the transporter in rat pinealocytes. This electrogenic transporter conducted inward current in response to L-glutamate and L- or D-aspartate and depolarized the membrane in patch-clamp experiments. Ca 2+ imaging demonstrated that the transporter-mediated depolarization induced a significant Ca2+ influx through voltage-gated Ca 2+ channels. The Ca2+ rise finally evoked glutamate exocytosis as detected by carbon-fiber amperometry and by HPLC. In pineal slices with densely packed pinealocytes, glutamate released from the cells effectively activated glutamate transporters in neighboring cells. The Ca2+ signal generated by KCl depolarization or acetylcholine propagated through several cell layers by virtue of the regenerative "glutamate-induced glutamate release." Therefore, we suggest that glutamate transporters mediate synchronized elevation of L-glutamate and thereby efficiently downregulate melatonin secretion via previously identified inhibitory metabotropic glutamate receptors in the pineal gland.

Original languageEnglish
Pages (from-to)10852-10863
Number of pages12
JournalJournal of Neuroscience
Volume28
Issue number43
DOIs
Publication statusPublished - Oct 22 2008

Fingerprint

Amino Acid Transport System X-AG
Pineal Gland
Glutamic Acid
D-Aspartic Acid
Metabotropic Glutamate Receptors
Exocytosis
Presynaptic Terminals
Melatonin
Acetylcholine
Down-Regulation
High Pressure Liquid Chromatography
Membranes

Keywords

  • Calcium
  • Depolarization
  • Glutamate transporters
  • Patch clamp
  • Pineal
  • Secretion

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Kim, M. H., Uehara, S., Muroyama, A., Hille, B., Moriyama, Y., & Koh, D. S. (2008). Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland. Journal of Neuroscience, 28(43), 10852-10863. https://doi.org/10.1523/JNEUROSCI.0894-08.2008

Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland. / Kim, Mean Hwan; Uehara, Shunsuke; Muroyama, Akiko; Hille, Bertil; Moriyama, Yoshinori; Koh, Duk Su.

In: Journal of Neuroscience, Vol. 28, No. 43, 22.10.2008, p. 10852-10863.

Research output: Contribution to journalArticle

Kim, MH, Uehara, S, Muroyama, A, Hille, B, Moriyama, Y & Koh, DS 2008, 'Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland', Journal of Neuroscience, vol. 28, no. 43, pp. 10852-10863. https://doi.org/10.1523/JNEUROSCI.0894-08.2008
Kim, Mean Hwan ; Uehara, Shunsuke ; Muroyama, Akiko ; Hille, Bertil ; Moriyama, Yoshinori ; Koh, Duk Su. / Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland. In: Journal of Neuroscience. 2008 ; Vol. 28, No. 43. pp. 10852-10863.
@article{0e683ee0e2ba4293951648cc0dfe412f,
title = "Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland",
abstract = "Glutamate transporters are expressed throughout the CNS where their major role is to clear released glutamate from presynaptic terminals. Here, we report a novel function of the transporter in rat pinealocytes. This electrogenic transporter conducted inward current in response to L-glutamate and L- or D-aspartate and depolarized the membrane in patch-clamp experiments. Ca 2+ imaging demonstrated that the transporter-mediated depolarization induced a significant Ca2+ influx through voltage-gated Ca 2+ channels. The Ca2+ rise finally evoked glutamate exocytosis as detected by carbon-fiber amperometry and by HPLC. In pineal slices with densely packed pinealocytes, glutamate released from the cells effectively activated glutamate transporters in neighboring cells. The Ca2+ signal generated by KCl depolarization or acetylcholine propagated through several cell layers by virtue of the regenerative {"}glutamate-induced glutamate release.{"} Therefore, we suggest that glutamate transporters mediate synchronized elevation of L-glutamate and thereby efficiently downregulate melatonin secretion via previously identified inhibitory metabotropic glutamate receptors in the pineal gland.",
keywords = "Calcium, Depolarization, Glutamate transporters, Patch clamp, Pineal, Secretion",
author = "Kim, {Mean Hwan} and Shunsuke Uehara and Akiko Muroyama and Bertil Hille and Yoshinori Moriyama and Koh, {Duk Su}",
year = "2008",
month = "10",
day = "22",
doi = "10.1523/JNEUROSCI.0894-08.2008",
language = "English",
volume = "28",
pages = "10852--10863",
journal = "Journal of Neuroscience",
issn = "0270-6474",
publisher = "Society for Neuroscience",
number = "43",

}

TY - JOUR

T1 - Glutamate transporter-mediated glutamate secretion in the mammalian pineal gland

AU - Kim, Mean Hwan

AU - Uehara, Shunsuke

AU - Muroyama, Akiko

AU - Hille, Bertil

AU - Moriyama, Yoshinori

AU - Koh, Duk Su

PY - 2008/10/22

Y1 - 2008/10/22

N2 - Glutamate transporters are expressed throughout the CNS where their major role is to clear released glutamate from presynaptic terminals. Here, we report a novel function of the transporter in rat pinealocytes. This electrogenic transporter conducted inward current in response to L-glutamate and L- or D-aspartate and depolarized the membrane in patch-clamp experiments. Ca 2+ imaging demonstrated that the transporter-mediated depolarization induced a significant Ca2+ influx through voltage-gated Ca 2+ channels. The Ca2+ rise finally evoked glutamate exocytosis as detected by carbon-fiber amperometry and by HPLC. In pineal slices with densely packed pinealocytes, glutamate released from the cells effectively activated glutamate transporters in neighboring cells. The Ca2+ signal generated by KCl depolarization or acetylcholine propagated through several cell layers by virtue of the regenerative "glutamate-induced glutamate release." Therefore, we suggest that glutamate transporters mediate synchronized elevation of L-glutamate and thereby efficiently downregulate melatonin secretion via previously identified inhibitory metabotropic glutamate receptors in the pineal gland.

AB - Glutamate transporters are expressed throughout the CNS where their major role is to clear released glutamate from presynaptic terminals. Here, we report a novel function of the transporter in rat pinealocytes. This electrogenic transporter conducted inward current in response to L-glutamate and L- or D-aspartate and depolarized the membrane in patch-clamp experiments. Ca 2+ imaging demonstrated that the transporter-mediated depolarization induced a significant Ca2+ influx through voltage-gated Ca 2+ channels. The Ca2+ rise finally evoked glutamate exocytosis as detected by carbon-fiber amperometry and by HPLC. In pineal slices with densely packed pinealocytes, glutamate released from the cells effectively activated glutamate transporters in neighboring cells. The Ca2+ signal generated by KCl depolarization or acetylcholine propagated through several cell layers by virtue of the regenerative "glutamate-induced glutamate release." Therefore, we suggest that glutamate transporters mediate synchronized elevation of L-glutamate and thereby efficiently downregulate melatonin secretion via previously identified inhibitory metabotropic glutamate receptors in the pineal gland.

KW - Calcium

KW - Depolarization

KW - Glutamate transporters

KW - Patch clamp

KW - Pineal

KW - Secretion

UR - http://www.scopus.com/inward/record.url?scp=58149347136&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=58149347136&partnerID=8YFLogxK

U2 - 10.1523/JNEUROSCI.0894-08.2008

DO - 10.1523/JNEUROSCI.0894-08.2008

M3 - Article

VL - 28

SP - 10852

EP - 10863

JO - Journal of Neuroscience

JF - Journal of Neuroscience

SN - 0270-6474

IS - 43

ER -