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The article presents a study carried out to analyze how the function of native and recombinant nicotinic acetylcholine receptors (nAChRs) is modulated by the monoterpenoid alcohol from peppermint menthol. Topics discussed include use of cell culture from Wistar rats in the study, examination of cultured cell by electrophysiology assay and data analysis by PulseFit software.

We have recently reported that the bioactive lipid sphingosine-1-phosphate (S1P), usually signaling proliferation and anti-apoptosis induces neuronal death when generated by sphingosine-kinase2 and when accumulation due to S1P-lyase deficiency occurs. In the present study, we identify the signaling cascade involved in the neurotoxic effect of sphingoid-base phosphates. We demonstrate that the calcium-dependent cysteine protease calpain mediates neurotoxicity by induction of the endoplasmic reticulum stress-specific caspase cascade and activation of cyclin-dependent kinase5 (CDK5). The latter is involved in an abortive reactivation of the cell cycle and also enhances tau phosphorylation. Neuroanatomical studies in the cerebellum document for the first time that indeed neurons with abundant S1P-lyase expression are those, which degenerate first in S1P-lyase-deficient mice. We therefore propose that an impaired metabolism of glycosphingolipids, which are prevalent in the central nervous system, might be linked via S1P, their common catabolic intermediate, to neuronal death. [ABSTRACT FROM AUTHOR]

Inhibitory glycine receptor (GlyR) and GABAA receptor (GABAAR)-mediated synaptic transmission was examined in two strains of the GlyR mutant mouse spastic and the respective wild types. The mutants display a mild and a severe neurological phenotype. Electrically evoked postsynaptic whole-cell currents were recorded from α-motoneurons in lumbar spinal cord slices. Amplitudes of GlyR-mediated IPSCs were significantly reduced in the severe phenotype in comparison to the respective wild type and the mild phenotype mutants. Surprisingly, amplitudes of GABAAR-mediated IPSCs were also significantly reduced in both mutants. Fast time constants of the decay phase of IPSCs were slightly reduced for the GlyR-mediated IPSCs and significantly larger for the GABAAR-mediated IPSCs in both mutant strains. [Copyright &y& Elsevier]