introduction: we previously shown that microinjection of glutamate into the hdb of rat elicited cardiovascular depressive responses. microinjection of ap5 (an nmda receptor antagonist, 2.5 mm, 50 nl) and cnqx (an ampa receptor antagonist, 1 mm, 50 nl) caused no significant changes in the blood pressure and heart rate. microinjection of bicuculline (bmi: a gabaa receptor antagonist, 1 mm, 50 nl)...

In the CNS, gamma-aminobutyric acid (GABA) affects neuronal activity through both the ligand-gated GABAA receptor channel and the G protein-coupled GABAB receptor. In the mature nervous system, both receptor subtypes decrease neural excitability, whereas in most neurons during development, the GABAA receptor increases neural excitability and raises cytosolic Ca2+ levels. We used Ca2+ digital im...

Using human g-aminobutyric acid type A (GABAA) receptor subunit combinations, expressed in cell lines and Xenopus laevis oocytes, the pharmacology of a number of ligands interacting directly with the GABA recognition site has been studied in [H]muscimol binding and electrophysiologically. The binding affinity of GABAA agonist and antagonist ligands showed small but statistically significant dep...

Introduction: We previously shown that microinjection of glutamate into the hDB of rat elicited cardiovascular depressive responses. Microinjection of AP5 (an NMDA receptor antagonist, 2.5 mM, 50 nl) and CNQX (an AMPA receptor antagonist, 1 mM, 50 nl) caused no significant changes in the blood pressure and heart rate. Microinjection of bicuculline (BMI: a GABAA receptor antagonist, 1 mM, 50...

Using human gamma-aminobutyric acid type A (GABAA) receptor subunit combinations, expressed in cell lines and Xenopus laevis oocytes, the pharmacology of a number of ligands interacting directly with the GABA recognition site has been studied in [3H]muscimol binding and electrophysiologically. The binding affinity of GABAA agonist and antagonist ligands showed small but statistically significan...

in the present study, the effect of gaba (γ-aminobutyric acid) receptor agonists and antagonists on morphine-induced antinociception was investigated in formalin test in rats. intraperitoneal (i.p.) injection of different doses of morphine (1, 3, 6 and 9 mg/kg) and intracerebroventricular (i.c.v.) injection of different doses of muscimol (0.5, 1 and 2 g/rat) or baclofen (0.25, 0.5 and 1 g/rat) ...

Gamma-aminobutyric acid (GABA) depolarizes dorsal root ganglia (DRG) primary afferent neurons through activation of Cl- permeable GABAA receptors but the physiologic role of GABAA receptors in the peripheral terminals of DRG neurons remains unclear. In this study, we investigated the role of peripheral GABAA receptors in nociception using a mouse model of acute inflammation. In vivo, peripheral...

In α-chloralose-anesthetized cats, we examined the role of GABAA, glycine, and opioid receptors in sacral neuromodulation-induced inhibition of bladder overactivity elicited by intravesical infusion of 0.5% acetic acid (AA). AA irritation significantly (P < 0.01) reduced bladder capacity to 59.5 ± 4.8% of saline control. S1 or S2 dorsal root stimulation at threshold intensity for inducing refle...

There are coflicting reports regarding the role of GABA in morphine analgesia. While-sorne investigators have reported that treatment with GABAA receptor agonist muscimol and GABA transaminase inhibitors potentiates morphine analgesia (2.4.6) others have reported antagonism of morphine analgesia (8.10). In view of these conflicting reports and since the analgesic profile 'of THIP, a GABAA recep...

Alterations of synaptic excitation induced by exposure to gamma-aminobutyric acid-A (GABAA) receptor antagonists were investigated employing tight-seal whole cell recording from single neurons or pairs of neurons in rat embryonic midbrain culture. Application of GABAA receptor antagonists led to sustained depolarizations followed by synchronous paroxysmal depolarization shifts (PDSs). PDSs indu...