title: O-phosphohomoserine, a naturally occurring analogue of phosphonate amino acid antagonists, is an N-methyl-D-aspartate (NMDA) antagonist in rat hippocampus.
abstract: O-Phosphohomoserine, an analogue of the excitatory amino acid antagonist 2-amino-phosphonovalerate, has been synthesized and tested for activity as an excitatory amino acid antagonist. The tests were carried out on 500 micron thick slices of rat hippocampus superfused in vitro at 30 degrees C. Antidromic and orthodromic potentials were studied in the CA1 region, recording from the pyramidal cell layer. At concentrations of 0.5 and 1 mM the compound produced a weak but significant antagonism of the depression of evoked potentials produced by N-methyl-D-aspartate with no effect on the responses produced by kainic or quisqualic acids. O-Phosphohomoserine was not metabolised by brain homogenates or by alkaline phosphatases. Since O-phosphohomoserine is known to occur naturally in lower organisms, it would be of interest to seek its existence in the animal nervous system.
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors; D004347:Drug Interactions; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects*; D006714:Homoserine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D007608:Kainic Acid / Q000008:administration & dosage; D016202:N-Methylaspartate; D010069:Oxadiazoles / Q000008:administration & dosage; D016318:Quisqualic Acid; D051381:Rats
chemical_list: D010069:Oxadiazoles; D001224:Aspartic Acid; C011066:O-phosphohomoserine; D016202:N-Methylaspartate; D006714:Homoserine; D016318:Quisqualic Acid; D007608:Kainic Acid