Intracellular recordings were made from presumed dopamine-containing neurons in slices cut from the midbrain of the rat. Focal electrical stimulation produced a hyperpolarizing synaptic potential that was reduced by 75-95% by the GABAB-receptor antagonist 2-hydroxysaclofen (300 microM). 5-HT (3-100 microM) reduced the amplitude of the GABAB synaptic potential by 20-74%, with a 50% reduction at ...

Exposure to acute psychological or physical stress increases core body temperature (stress-induced hyperthermia, SIH) which is part of the autonomic stress response. SIH is used as a putative rodent anxiety paradigm in which anxiolytic drugs reduce the SIH response. The predictive validity of the SIH paradigm has proven to be good, making it suitable to detect the putative anxiolytic properties...

PURPOSE To investigate the role of γ-aminobutryic acid (GABA) in the regulation of arteriolar diameter in the rat retina. METHODS The actions of GABA on arteriolar diameter were examined using ex vivo retinal whole-mount preparations and isolated vessel segments. In most experiments, arterioles were partially preconstricted with endothelin (Et)-1. The expression levels of GABAA and GABAB rece...

gamma-Aminobutyric acid (GABA)A receptor-mediated inhibitory synaptic transmission in visual cortex undergoes long-term potentiation (LTP), which is input-specific and associative. The present study, conducted under a blockade of ionotropic glutamate receptors, demonstrates an induction mechanism of LTP considerably different from those of associative LTP at excitatory synapses. Inhibitory resp...

Quantitative receptor autoradiography was used to assess GABAB receptor binding in three primary subdivisions of the inferior colliculus (IC): dorsal cortex (DCIC), external cortex (ECIC), and the central nucleus (CIC) of 3-, 18-20-, and 26-month-old Fischer 344 rats. GABAB binding sites were localized using [3H]GABA in the presence of a saturating concentration of isoguvacine, a selective GABA...

We investigated the effects of intrathecal application of GABAA- or GABAB-receptor agonists on detrusor-sphincter dyssynergia (DSD) in spinal cord transection (SCT) rats. Adult female Sprague-Dawley rats were used. At 4 wk after Th9-10 SCT, simultaneous recordings of intravesical pressure and urethral pressure were performed under an awake condition to examine the effect of intrathecal applicat...

Brain nicotinic acetylcholine receptors (nAChRs) reportedly suppress the micturition, but mechanisms responsible for this suppression remain unclear. We previously reported that intracerebroventricularly administered (±)-epibatidine (non-selective nAChR agonist) activated sympatho-adrenomedullary system, which can affect micturition. Therefore, we investigated (1) whether (±)-epibatidine-induce...

The neural circuitry and pharmacology underlying transient signal formation at the bipolar-amacrine cell interface were studied. Synaptic currents were measured with whole cell patch clamp in retinal slices. Cell types were identified with Lucifer yellow staining. Activity was initiated with puffs of kainate of known time course and spatial spread delivered at bipolar dendrites. OFF bipolar cel...