OBJECTIVES We sought to identify the triggers of ventricular tachyarrhythmia (VTA) in experimental models of long QT type 2 (LQT2) and long QT type 3 (LQT3) syndromes. BACKGROUND Most adverse cardiac events occurring in the long QT type 1 syndrome are related to sympathetic nerve activity. In contrast, various factors may trigger VTA in patients with LQT2 and LQT3. METHODS The mode of onset...

It has been shown that L-arginine like the abused drugs could release dopamine from meso-cortico-limbic system. The purpose of the present study was to compare the effect of L-arginine with morphine as a standard abuse drug in the induction of conditioned place preference (CPP) in rat. For this purpose, male Wistar rats (250-300 g) were used in the experiments. Five days after surgical cannulat...

Microdialysis was used to assess the contribution to cocaine seeking of cholinergic input to the mesocorticolimbic dopamine system in ventral tegmental area (VTA). VTA acetylcholine (ACh) was elevated in animals lever pressing for intravenous cocaine and in cocaine-experienced and cocaine-naive animals passively receiving similar "yoked" injections. In cocaine-trained animals, the elevations co...

The hippocampus receives dopaminergic projections from the ventral tegmental area (VTA). Modulatory effect of dopamine on hippocampal long term potentiation (LTP) has been studied before, but there are conflicting results and some limitations in previous reports. Most of these studies show a significant effect of dopamine on the late phase of LTP in CA1 area of the hippocampus, while few report...

This research investigated the effect of an increase or decrease in opioid activity in the ventral tegmental area (VTA) on the onset of maternal behavior in rats. In Experiment 1, the latency to show maternal behavior toward foster rat pups (sensitization latency) was determined in maternally naive female rats given either nothing or a unilateral intra-VTA injection of morphine sulfate (MS) (0....

Dysfunction of the dopaminergic ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) is implicated in psychiatric disorders including attention-deficit/ hyperactivity disorder (ADHD), addiction, schizophrenia and movement disorders such as Parkinson's disease (PD). Although the prevalence of these disorders varies by age and sex, the underlying neural mechanism is not well unde...

Optogenetics is a powerful tool for controlling biological functions using light. Optical fibers have been extensively utilized in optical stimulation devices optogenetics. However, the use of results small photo-stimulation region. In this study, micro-LED array were developed to achieve large-area brain large animal, such as macaque monkeys. Planar and linear designed fabricated photo-stimula...

Normal aging is associated with neuronal loss in the dopaminergic midbrain (substantia nigra/ventral tegmental area, SN/VTA), a region that has recently been implicated in processing novel stimuli as part of a mesolimbic network including the hippocampus. Here, we quantified age-related structural degeneration of the mesolimbic system using magnetization transfer ratio (MTR) and correlated it w...

The objective of the present study was to examine the effects of perfusion of dopamine (DA) D1- and D2-like receptor agonists in the nucleus accumbens (ACB) on the long-loop negative feedback regulation of mesolimbic somatodendritic DA release in the ventral tegmental area (VTA) of Wistar rats employing ipsilateral dual probe in vivo microdialysis. Perfusion of the ACB for 60 min with the D1-li...