Serotonin (5-HT) is a major modulator of the CNS. In motoneurons recorded in slices of the spinal cord, 5-HT promotes plateau potentials mediated by the activity of low-threshold L-type calcium channels (CaV1.3). However, no direct evidence has shown that 5-HT actually promotes plateau potentials under physiological conditions. Here, we investigate how release of 5-HT induced by activation of t...

Diabetes Mellitus (DM) is one of the most important metabolic disease causes in many side effects. The decrease of mental abilities and even some form of dementia followed prolonged diabetes has been reported. There are evidences that show hippocampus might be the site of neural involvement in patients with dementia followed diabetes. As hippocampus received main serotonergic efferents from bra...

Learned helplessness, the failure to escape shock induced by uncontrollable aversive events, was discovered half a century ago. Seligman and Maier (1967) theorized that animals learned that outcomes were independent of their responses-that nothing they did mattered-and that this learning undermined trying to escape. The mechanism of learned helplessness is now very well-charted biologically, an...

The subthalamic nucleus-globus pallidus network is a potential source of oscillations in Parkinson's disease, but the mechanism is unknown. In this issue of Neuron, Chu et al. (2015) present a cortically driven form of heterosynaptic plasticity that could promote oscillatory activity after dopamine depletion.

Abstract —The mechanisms of the ketamine antidepressant effects observed in humans and laboratory animals are not fully understood. To further clarify role brain serotonergic (5-HT) activity action drugs, optogenetic inhibition 5-HT neurons rat dorsal raphe nucleus (DRN) was applied. In control animals, a subanesthetic dose alleviated their depressive-like behavior tail suspension test. Inhibit...

A significant number of postmenopausal women report increased anxiety and vulnerability to stress, which has been linked to decreased secretion of ovarian steroids. Communication between the serotonin system and the corticotropin releasing factor (CRF) system determines stress sensitivity or resilience. This study examines the effects of the ovarian steroids, estradiol (E) and progesterone (P) ...

In order to localize the cells expressing 5-HT1A receptors in the rat brain, we used in situ hybridization histochemistry to visualize the distribution of the mRNA coding for 5-HT1A receptors. Oligonucleotides derived from different parts of the coding region of the rat 5-HT1A receptor gene were used as hybridization probes. 5-HT1A binding sites were visualized on consecutive sections by recept...

The effects of MDMA (3,4-methylenedioxymethamphetamine) on the activity of serotonin (5-HT)-containing dorsal raphe neurons were characterized using extracellular single-unit recording and microdialysis techniques in the in vitro midbrain slice preparation. Addition of (+)-MDMA, (-)-MDMA or p-chloroamphetamine (PCA) to the superfusate (final concentration 3-100 microM) produced a concentration-...

The dorsal raphe nucleus is the major source of serotonin in the brain. It is connected to brain regions related to reward processing, and the neurons show activity related to predicted reward outcome. Clinical observations also suggest that it is important in maintaining alertness and its apparent role in addiction seems to be related to reward processing. Here, we examined whether the neurons...