Alteration of Na+ currents in dorsal root ganglion neurons from rats with a painful neuropathy.

Increased excitability of primary sensory neurons may be important for the generation of neuropathic pain from nerve injury. The currents underlying the action potentials of these neurons are largely carried by Na+, and changes in Na+ currents have been postulated to contribute to this increased excitability. Using patch clamp in whole-cell mode, we recorded Na+ currents from DRG neurons freshly isolated from rats with a chronic constriction injury (CCI), an animal model of neuropathic pain.

Spontaneous action potential activity in isolated dorsal root ganglion neurons from rats with a painful neuropathy.

One of the physiological changes accompanying neuropathic pain from nerve injury is the spontaneous firing of primary afferent fibers. At least some of this activity is thought to arise from the dorsal root ganglion. We have investigated whether this activity is resident in the cell bodies of dorsal root ganglion neurons and if it is retained in vitro.

Isoflurane inhibits multiple voltage-gated calcium currents in hippocampal pyramidal neurons.

Background: The mechanisms by which volatile anesthetics produce general anesthesia are unknown. Voltage-gated calcium currents in central neurons are potential target sites for general anesthetics because they are involved in the regulation of excitability and are essential for synaptic transmission.

Methods: Freshly isolated rat hippocampal pyramidal neurons were studied using the whole-cell patch clamp method.

Depression of benzodiazepine binding and diazepam potentiation of GABA-mediated inhibition after chronic exposure of spinal cord cultures to diazepam.

Cultures of fetal mouse spinal cord were exposed to 12.6 microM (3.6 micrograms/ml) diazepam for 7 days.