BACKGROUND Brexpiprazole was recently approved as adjunctive therapy for depression and treatment of schizophrenia in adults. To complement results from a previous study in which its acute effects were characterized, the present study assessed the effect of repeated brexpiprazole administration on monoaminergic systems. METHODS Brexpiprazole (1mg/kg, subcutaneous) or vehicle was administered ...

Using non-fluorescent immunocytochemical double-labelling procedure and specific antibodies visualizing GR (glucocorticoid receptors) and TH (tyrosine hydroxylase) we have been looking for the co-localization of both antigens in neurons of the rat ventral tegmental area and adjacent substantia nigra. This experimental direction has been inspired by the available data showing that alterations in...

There is evidence of a second neutral pion from: (1) the anomalous branching ratios in the reactions p p → ππ and p d → ππN , and (2) the 1960’s results of Tsai-Chü et al. for antinucleon annihilation stars in emulsions. The anomaly of (1) is eliminated if the two neutral pions in the reactions p p → π π and p d → π π n are not identical. Tsai-Chü et al. observed a second neutral pion that “dec...

In response to behaviorally salient stimuli, dopamine (DA) neurons fire in bursts. Burst firing induces a large transient increase in synaptic DA and is regarded as the functionally relevant mode of transmission that signals reward and modulates goal-directed behavior. DA neuron burst firing is dynamically regulated by afferent inputs, and it is not present in vitro because of severing of affer...

The brainstem tegmental pedunculopontine nucleus (TPP) is involved in reward signalling and is functionally and anatomically linked to the VTA. We examined the possible role of the TPP as a reward transmission output for GABAA receptors in the VTA in rats not previously exposed to opiates vs. rats that were chronically exposed to and in withdrawal from opiates or in rats that had recovered from...

Nicotine, the primary psychoactive component of tobacco smoke, is known to possess potent rewarding and aversive stimulus properties. The mammalian ventral tegmental area (VTA) is involved importantly in the mediation of the motivational effects of nicotine. However, the neural outputs from the VTA that may be involved in the transmission of the rewarding and aversive motivational effects of ni...

The role of ascending and descending fibers in self-stimulation of the lateral hypothalamus and ventral tegmental area in the rat was assessed by noting whether anodal hyperpolarization of one of these sites could reduce the rewarding effect of stimulating the other site. Strength-duration curves were obtained by psychophysical means, with one of the depth electrodes serving as the cathode and ...

We sought to determine the long-term changes produced by neonatal sex hormone administration on the functioning of midbrain dopaminergic neurons in adult male rats. Sprague-Dawley rats were injected subcutaneously at postnatal day 1 and were assigned to the following experimental groups: TP (testosterone propionate of 1.0 mg/50 μL); DHT (dihydrotestosterone of 1.0 mg/50 μL); EV (estradiol valer...

We investigated the effect of estrogen on cocaine-induced brain activity using blood oxygen level-dependent (BOLD) magnetic resonance imaging. Ovariectomized (Ovx) rats without estrogen and Ovx rats with estrogen (Ovx+E) were given a single saline or cocaine injection (15 mg/kg, i.p.) for 5 d. After 7 d of withdrawal from injections, rats were challenged with cocaine during functional imaging. ...

As models of shared expectations, social norms play an essential role in our societies. Since our social environment is changing constantly, our internal models of it also need to change. In humans, there is mounting evidence that neural structures such as the insula and the ventral striatum are involved in detecting norm violation and updating internal models. However, because of methodologica...