Background: The ventral tegmental area (VTA) is well known for its role in cardiovascular control. It is demonstrated that about 20-30% of the VTA neurons are GABAergic though their role in cardiovascular control is not yet understood. This study is carried out to find the effects of GABA A and GABA B receptors on cardiovascular response of the VTA. Methods: Experiments were performed on uretha...

N,N -Dicyclopentyl-2-methylsulfanyl-5-nitro-pyrimidine-4,6diamine (GS39783) and structurally related compounds are described as novel allosteric enhancers of GABAB receptor function. They potentiate GABA-stimulated guanosine 5 -O-(3-[S]thio)triphosphate ([S]GTP S) binding to membranes from a GABAB(1b/2)-expressing Chinese hamster ovary cell line at low micromolar concentrations, but do not stim...

The g-aminobutyric acid (GABA) receptor type B (GABABR) is constituted of at least two homologous proteins, GABABR1 and GABABR2. These proteins share sequence and structural similarity with metabotropic glutamate and Ca-sensing receptors, both of which are sensitive to Ca. Using rat brain membranes, we report here that the affinity of GABA and 3-aminopropylphosphinic acid for the GABABR recepto...

The objective of this study was to evaluate effects of baclofen, a γ-aminobutyric acid type B (GABAB) receptor agonist, injected into the nucleus of the solitary tract, on the Hering-Breuer inspiratory-inhibitory (Ti-inhibitory) and deflation reflexes in urethan-anesthetized adult Wistar rats ( n = 7). The Ti-inhibitory reflex was estimated from changes in peak amplitude of the integrated diaph...

It is now well established that G protein-coupled receptors can exist not only as homodimers, but also as heterodimers or higher order oligomers. However, whether and how dimerization of the receptors is regulated is poorly understood. In this issue of The EMBO Journal, the team of Marc Landry provides evidence for an intriguing mechanism by which—under pathological conditions—GABAB receptor he...

In neocortex, synaptic inhibition is mediated by gamma-aminobutyric acid-A (GABAA) and GABAB receptors. By using intracellular and patch-clamp recordings in slices of rat visual cortex we studied the balance of excitation and inhibition in different intracortical pathways. The study was focused on the strength of fast GABAA- and slow GABAB-mediated inhibition in interareal forward and feedback ...

1. Extracellular single unit recording techniques were used to compare the effects of (-)-3-amino-1-hydroxypyrrolidin-2-one ((-)-HA-966) and (+/-)-baclofen on the activity of dopamine-containing neurones in 300 microns slices of rat substantia nigra. Electrophysiological data were compared with the outcome of in vitro binding experiments designed to assess the affinity of (-)-HA-966 for gamma-a...