2-Amino-7-phosphonoheptanoic acid depresses gamma-motoneurons and polysynaptic reflexes in the cat spinal cord.
The effects of 2-amino-7-phosphonoheptanoic acid (APH), a selective antagonist of N-methyl-D-aspartate (NMDA) receptors, were studied on spinal cord functions in unanaesthetized spinal cats. APH (10 mg/kg i.v.) depressed spontaneous activity of gamma-motoneurons and segmental polysynaptic ventral root reflexes (VRRs) without affecting monosynaptic VRRs. The NMDA-induced enhancement of polysynaptic VRRs and activation of gamma-motoneurons were antagonized by APH. The results support the hypothesis that NMDA receptors are involved in the polysynaptic excitation of motoneurons, including gamma-motoneurons, and thus participate in motor functions of the spinal cord.
D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives*; D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D002415:Cats; D003864:Depression, Chemical; D009046:Motor Neurons / Q000187:drug effects*; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000378:metabolism; D012018:Reflex / Q000187:drug effects*; D013116:Spinal Cord / Q000187:drug effects*
D000596:Amino Acids; D000927:Anticonvulsants; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D015763:2-Amino-5-phosphonovalerate; C031231:2-amino-7-phosphonoheptanoic acid