Interaction of androsterone and progesterone with inhibitory ligand-gated ion channels: a patch clamp study.

Gamma-aminobutyric acid receptor type A (GABA(A)) receptor channels mediate fast inhibitory neurotransmission throughout the central nervous system while the expression of ionotropic glycine receptors is mainly restricted to the spinal cord and brain stem. Neuroactive steroids are well known as positive allosteric modulators of GABA(A) receptor function. Furthermore, there have been hints for an interaction of neuroactive steroids with ionotropic glycine receptors.

Interaction of topiramate with glycine receptor channels.

Glycine receptor channels are pentameric ligand-gated ion channels that respond to the application of inhibitory neurotransmitters by opening of a chloride-selective central pore. Topiramate (TPM) is a broad-spectrum antiepileptic drug used as add-on or monotherapy for focal seizures. In the present study the interaction of TPM with glycine receptor channels was studied on outside-out patches from HEK293 cells expressing alpha1beta glycine receptor channels.

Effects of propofol on recombinant AMPA receptor channels.

The interaction of the anaesthetic propofol with recombinant human AMPA-type glutamate receptor channels was investigated by a patch-clamp study using fast agonist application techniques. Despite the marked effects of propofol on inhibitory synaptic transmission and voltage gated sodium channels, there is also evidence for a specific pharmacological action on AMPA receptors. In our study, we observed a deceleration of AMPA receptor channel desensitization in the prolonged presence of glutamate and propofol that is likely to account for the enhancement of ion currents through AMPA receptor channels observed in previous studies.

c-Myb protein interacts with Rcd-1, a component of the CCR4 transcription mediator complex.

Transcriptional initiation of eukaryotic genes depends on the cooperative interaction of various transcription factors. Using the yeast two-hybrid assay, we have identified the murine Rcd-1 protein as a cofactor of the c-myb proto-oncogene product. Rcd-1 is evolutionarily conserved among many species, and moreover the yeast homologue CAF40 is part of the carbon catabolite repressor protein transcriptional mediator thought to be involved in the negative regulation of genes transcribed by RNA polymerase II.

Two different modes of action of pentobarbital at glycine receptor channels.

Glycine receptor channels are pentameric ligand-gated ion channels which respond to the binding of inhibitory transmitters by opening of a chloride-selective central pore. Pentobarbital is widely used as an anticonvulsive, hypnotic and anaesthetic drug. In the present study, the interaction between pentobarbital and glycine receptor channels was studied on outside-out patches of human embryonic kidney (HEK) 293 cells expressing alpha(1)beta glycine receptor channels.