Pentobarbital enhances gamma-aminobutyric acid-mediated excitation without altering synaptic plasticity in rat hippocampus.

Background: Synaptic plasticity is thought to provide a molecular mechanism for learning and memory. N-methyl-d-aspartate receptor-mediated plasticity requires that N-methyl-d-aspartate receptor activation coincides with postsynaptic depolarizing potentials (DPSP(A)'s). Pentobarbital, in high concentrations, enhances DPSP(A)'s, but high concentrations suppress synaptic plasticity, probably by impairing glutamatergic transmission.

Levetiracetam reduces anesthetic-induced hyperalgesia in rats.

Background: As part of an increase in excitability, small doses of pentobarbital, propofol, and midazolam induce an increased sensitivity to pain. Specific therapy to prevent or reduce this excitability may offer advantages over current clinical management with analgesics and sedatives. The pharmacological profile of the novel antiepileptic drug, levetiracetam, suggests that it may reduce the intensity of the excitatory stages of anesthesia.

Spinal carbonic anhydrase contributes to nociceptive reflex enhancement by midazolam, pentobarbital, and propofol.

Background: Systemic administration of acetazolamide blocks nociceptive hyperreflexia induced by pentobarbital. The authors assessed the effect of intrathecal carbonic anhydrase inhibitors (CAIs) on nociceptive reflex enhancement by pentobarbital, propofol, and midazolam.

Methods: Twenty-seven rats with chronic indwelling subarachnoid catheters were studied.