Pharmacology, biochemistry, and behavior
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Pharmacol. Biochem. Behav. · May 1994
Evidence of a role for N-methyl-D-aspartate (NMDA) receptors in the facilitation of tail withdrawal after spinal transection.
Peripheral injury produces a characteristic excitation of spinal cord dorsal horn cells (wind-up) which is associated with a facilitation of spinal nociceptive reflexes (hyperalgesia). These phenomena are believed to be mediated by a trauma-induced increase in the release of excitatory amino acids (EAAs). A similar increase in the activity of dorsal horn neurons and spinal reflexes occurs after spinal transection. ⋯ However, both systemic and intrathecal ketamine significantly increased TF latencies in spinal, relative to intact rats. These results indicate that ketamine did not prevent the development of spinal reflex facilitation, but it selectively reduced this reaction once it was established in spinal rats. The data support an involvement of EAAs in reflex facilitation produced by spinal transection.
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Pharmacol. Biochem. Behav. · May 1994
Effects of valine, leucine, isoleucine, and a balanced amino acid solution on the seizure threshold to picrotoxin in rats.
During infusion of branched-chain amino acids (BCAAs) in humans, changes in ventilatory drive, sleeping pattern, and appetite have been reported. The mechanism by which BCAA exerts their effects on CNS remains unclear. ⋯ A balanced amino acid solution (Vamin-Glucose) had no effect on the seizure threshold. Thus, these CNS effects are specific for BCAAs and occur with all three.