Synthesis, accumulation, and release of d-aspartate in the Aplysia californica CNS.
d-Aspartate (d-Asp) is an endogenous molecule that is often detected in CNS and endocrine tissues. Using capillary electrophoresis and a variety of radionuclide detection techniques, we examine the synthesis, release, and uptake/accumulation of d-Asp in the CNS of the marine mollusk Aplysia californica. We observe the preferential synthesis and accumulation of d-Asp over l-aspartate (l-Asp) in neuron-containing ganglia compared to surrounding sheath tissues. Little conversion of d-Asp to l-Asp is detected. The Ca(2+) ionophore ionomycin and elevated extracellular potassium stimulates release of d-Asp from the cerebral ganglia. Lastly, radioactive d-Asp in the extracellular media is efficiently taken up and accumulated by individual F-cluster neurons. These observations point to a role for d-Asp in cell-to-cell signaling with many characteristics similar to classical transmitters.
Scanlan
Cory
C
Department of Chemistry and the Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801,USA.
Shi
Ting
T
Hatcher
Nathan G
NG
Rubakhin
Stanislav S
SS
Sweedler
Jonathan V
JV
D000818:Animals; D001048:Aplysia / Q000033:anatomy & histology; D002247:Carbon Isotopes / Q000378:metabolism; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism*; D026603:D-Aspartic Acid / Q000378:metabolism*; D019075:Electrophoresis, Capillary / Q000379:methods; D017952:Ganglia, Invertebrate / Q000166:cytology; D015759:Ionomycin / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D007834:Lasers; D011189:Potassium Chloride / Q000494:pharmacology; D011868:Radioisotopes; D013696:Temperature
D002247:Carbon Isotopes; D007476:Ionophores; D011868:Radioisotopes; D026603:D-Aspartic Acid; D015759:Ionomycin; D011189:Potassium Chloride