LOCALIZATION AND TRANSPORT OF N-ACETYLASPARTYLGLUTAMATE IN CELLS OF WHOLE MURINE BRAIN IN PRIMARY CULTURE

被引:37
作者
CASSIDY, M [1 ]
NEALE, JH [1 ]
机构
[1] GEORGETOWN UNIV,DEPT BIOL,37TH & O ST,WASHINGTON,DC 20057
关键词
NEUROPEPTIDE; UPTAKE; GLUTAMATE; NEUROTRANSMITTER; N-ACETYLASPARTYLGLUTAMATE; CELL CULTURE;
D O I
10.1111/j.1471-4159.1993.tb13385.x
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
N-Acetylaspartylglutamate (NAAG) is the most abundant neuropeptide in the mammalian nervous system. Considerable data support the hypothesis that NAAG is synaptically released in a manner consistent with neurotransmission. Primary murine brain cultures containing neurons and glia expressed 1.2-3.5 nmol of NAAG/mg of protein. In contrast to conclusions drawn from immunohistochemistry, pure glial cultures also expressed high levels of NAAG (0.6-2.11 nmol/mg of protein). These data suggest that although a subpopulation of neurons contains very high NAAG levels, micromolar concentrations of the peptide also are present in glia. Both culture types demonstrated robust extracellular peptidase activity when incubated with NAAG, as well as peptide transport. Uptake of [H-3]NAAG was both temperature and sodium dependent, yet relatively insensitive to the presence of extracellular glutamate. These results indicate that synaptically released NAAG, as well as that which may be released from glia, is removed from the extracellular space by direct uptake as well as the robust enzymatic degradation of the peptide. A kinetic analysis of this NAAG transport (estimated K(m) = 1.8 muM) suggests a high-affinity NAAG transport system. The balance of the two processes of direct peptide uptake and peptide hydrolysis would markedly influence the sequence of receptor-mediated events that follow NAAG release.
引用
收藏
页码:1631 / 1638
页数:8
相关论文
共 40 条
  • [1] LOCALIZATION OF N-ACETYLASPARTYLGLUTAMATE-LIKE IMMUNOREACTIVITY IN SELECTED AREAS OF THE RAT-BRAIN
    ANDERSON, KJ
    MONAGHAN, DT
    CANGRO, CB
    NAMBOODIRI, MAA
    NEALE, JH
    COTMAN, CW
    [J]. NEUROSCIENCE LETTERS, 1986, 72 (01) : 14 - 20
  • [2] AMINO-ACIDS AS CENTRAL NERVOUS TRANSMITTERS - INFLUENCE OF IONS, AMINO-ACID ANALOGS, AND ONTOGENY ON TRANSPORT-SYSTEMS FOR L-GLUTAMIC AND L-ASPARTIC ACIDS AND GLYCINE INTO CENTRAL NERVOUS SYNAPTOSOMES OF RAT
    BENNETT, JP
    LOGAN, WJ
    SNYDER, SH
    [J]. JOURNAL OF NEUROCHEMISTRY, 1973, 21 (06) : 1533 - 1550
  • [3] A RE-EXAMINATION OF THE INTERACTION OF N-ACETYL-L-ASPARTYL-L-GLUTAMATE WITH A SUBPOPULATION OF RAT-BRAIN MEMBRANE L-[H-3]GLUTAMATE BINDING-SITES
    BLAKELY, RD
    ROBINSON, MB
    GUARDA, AS
    COYLE, JT
    [J]. EUROPEAN JOURNAL OF PHARMACOLOGY, 1988, 151 (03) : 419 - 426
  • [4] BLAKELY RD, 1986, J NEUROCHEM, V47, P1013
  • [5] NONNEURONAL CELLS MEDIATE NEUROTROPHIC ACTION OF VASOACTIVE-INTESTINAL-PEPTIDE
    BRENNEMAN, DE
    NEALE, EA
    FOSTER, GA
    DAUTREMONT, SW
    WESTBROOK, GL
    [J]. JOURNAL OF CELL BIOLOGY, 1987, 104 (06) : 1603 - 1610
  • [6] IMMUNOHISTOCHEMISTRY AND BIOSYNTHESIS OF N-ACETYLASPARTYLGLUTAMATE IN SPINAL SENSORY GANGLIA
    CANGRO, CB
    NAMBOODIRI, MAA
    SKLAR, LA
    CORIGLIANOMURPHY, A
    NEALE, JH
    [J]. JOURNAL OF NEUROCHEMISTRY, 1987, 49 (05) : 1579 - 1588
  • [7] CASSIDY M, 1987, Society for Neuroscience Abstracts, V13, P1563
  • [8] CASSIDY M, 1991, Society for Neuroscience Abstracts, V17, P412
  • [9] FADEN AI, 1992, J NEUROSCI, V12, P425
  • [10] UPTAKE AND RELEASE OF PUTATIVE AMINO-ACID NEUROTRANSMITTERS
    FAGG, GE
    LANE, JD
    [J]. NEUROSCIENCE, 1979, 4 (08) : 1015 - 1036