Chorea is a basal-ganglia (BG) related hyperkinetic movement disorder characterized by irregular continuous involuntary movements. Chorea and related hyperbehavioral disorders may be induced in behaving primates by local microinjections of the GABA(A) antagonist bicuculline to the globus pallidus externus (GPe). We performed multielectrode extracellular recordings in the GPe and in the globus p...

The ventromedial medulla is implicated in a variety of functions including nociceptive and cardiovascular modulation and the control of thermoregulation. To determine whether single microinjections into the ventromedial medulla elicit changes in one or multiple functional systems, the GABA(A) receptor antagonist bicuculline was microinjected (70 nl, 5-50 ng) into the ventromedial medulla of lig...

In order to test the hypothesis that GABA is an inhibitory neurotransmitter restricting the release of LHRH before puberty, we examined the effects of pulsatile infusion of the GABA(A) receptor blocker, bicuculline, on the timing of puberty. Eleven female monkeys at 14-15 months of age were implanted with a stainless steel cannula into the base of the third ventricle above the median eminence. ...

The purpose of this study was to characterize the inhibitory mechanism(s) associated with directionally selective motion detection (DS) in nonspiking tangential cells of crayfish optic lobe. The experiments employed intracellular recording of synaptic potentials elicited with sinewave gratings and pharmacological techniques. Previous studies established that tangential cells are subject to bicu...

Objective(s): Central γ-aminobutyric acid (GABA) neurotransmission modulates cardiovascular functions and sleep. Acute sleep deprivation (ASD) affects functions of various body organs via different mechanisms. Here, we evaluated the effect of ASD on cardiac ischemia/reperfusion injury (IRI), and studied the role of GABA-A receptor inhibition in central nucleus of amygdala (CeA) by assessing nit...

This study used in vivo microdialysis in cat (n=12) to test the hypothesis that gamma aminobutyric acid A (GABAA) receptors in the pontine reticular formation (PRF) inhibit acetylcholine (ACh) release. Animals were anesthetized with halothane to hold arousal state constant. Six concentrations of the GABAA receptor antagonist bicuculline (0.03, 0.1, 0.3, 1, 3, and 10 mM) were delivered to a dial...

Obesity is often associated with a reduced ventilatory response and a decreased maximal exercise capacity. GABA is a major inhibitory neurotransmitter in the mammalian central nervous system. Altered GABAergic mechanisms have been detected in obese Zucker rats and implicated in their hyperphagic response. Whether altered GABAergic mechanisms also contribute to regulate ventilation and influence...

Bicuculline and its methochloride salt block inhibitory postsynaptic potentials recorded from giant interneurone 2 (GI 2) of the cockroach Periplaneta americana following stimulation of cercal nerve X, but fail to block the response to gamma-aminobutyric acid (GABA) when this neurotransmitter is ionophoresed or pressure-injected onto the fine branches of GI 2 within the neuropile of the termina...

The present study was performed to investigate the effects of depleting intracellular Ca(2+) stores on bicuculline- or gabazine-induced epileptiform excitability. Studies were performed on monolayer rat hippocampal neuronal networks utilising a system that allowed simultaneous multiple extracellular single-unit recordings of neuronal activity. Hippocampal neuronal networks were prepared from en...