title: Iminoglycine transport system in synaptosomes and its interaction with enkephalins.
abstract: Evidence is presented which suggests that proline, pipecolic acid, and glycine are accumulated by a common transport system in rat brain cortical synaptosomes and synaptosomal plasma membrane vesicles. This system is Na+ dependent and appears to be similar to the iminoglycine transport system present in renal tubules and in renal brush border membranes. The opioid pentapeptides Leu- and Met-enkephalin specifically inhibit the uptake of these three imino/amino acids, presumably by interaction with a nonopioid receptor, since the inhibition is not affected by the opiate antagonist naloxone and occurs with des-tyrosyl enkephalins as well as with the intact pentapeptides.
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002540:Cerebral Cortex / Q000378:metabolism*; D004743:Enkephalin, Leucine / Q000494:pharmacology*; D004744:Enkephalin, Methionine / Q000494:pharmacology*; D005998:Glycine / Q000378:metabolism; D007098:Imino Acids / Q000378:metabolism*; D007700:Kinetics; D009294:Narcotics / Q000494:pharmacology; D010875:Pipecolic Acids / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000494:pharmacology; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
chemical_list: D007098:Imino Acids; D009294:Narcotics; D010875:Pipecolic Acids; C033013:iminoglycine; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D011392:Proline; D012964:Sodium; C031345:pipecolic acid; D005998:Glycine