Comparison of synaptosomal and glial uptake of pipecolic acid and GABA in rat brain.
The active uptake of [3H]pipecolic acid increased with incubation time and its uptake at 3 min was half of that at 20 min. On the other hand, a ratio (pellet/medium) of [3H]pipecolic acid uptake into glial cell-enriched fractions, was much less (0.4 - 0.6) than that of [14C]GABA (25.8 - 74.1). GABA, 10(-4) M, and pipecolic acid, 10(-4) M, produced a significant inhibitor of [3H]pipecolic acid uptake into P2 fractions. Pipecolic acid, 10(-4) M, significantly reduced the synaptosomal and glial uptake of [14C]GABA. GABA, 10(-4) M, affected neither spontaneous nor high K+-induced release of [3H]pipecolic acid from brain slices. It is suggested that pipecolic acid is involved in either synaptic transmission or in its modulation at GABA synapses in the central nervous system.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009457:Neuroglia / Q000378:metabolism*; D009557:Nipecotic Acids / Q000494:pharmacology; D010875:Pipecolic Acids / Q000378:metabolism* / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011392:Proline / Q000031:analogs & derivatives*; D051381:Rats; D013574:Synaptosomes / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism* / Q000494:pharmacology
D009557:Nipecotic Acids; D010875:Pipecolic Acids; C030278:nipecotic acid; D005680:gamma-Aminobutyric Acid; D011392:Proline; C010983:homoproline; C031345:pipecolic acid; D011188:Potassium