Glutamate stimulation of 45Ca uptake by rat striatal synaptosomes.
The effects of acidic excitatory amino acids and 60 mM K+ on 45Ca uptake by synaptosomes prepared from rat striatum were examined. Both glutamic acid and 60 mM K+ significantly stimulated the uptake of 45Ca and these effects were antagonized by 30 mM Mg2+ and 0.5 mM La3+ but not by 5 microM tetrodotoxin. Neither kainic acid nor N-methyl-D,L-aspartic acid significantly affected the uptake of 45Ca. The results suggest that glutamate may activate a presynaptic receptor that is directly linked to calcium channels.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002132:Calcium Radioisotopes; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D005971:Glutamates / Q000494:pharmacology*; D018698:Glutamic Acid; D066298:In Vitro Techniques; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013574:Synaptosomes / Q000378:metabolism*; D013779:Tetrodotoxin / Q000494:pharmacology
D002132:Calcium Radioisotopes; D005971:Glutamates; D018698:Glutamic Acid; D013779:Tetrodotoxin; D011188:Potassium; D002118:Calcium