Clozapine is a second-generation (atypical) antipsychotic agent, which has been proven efficient against the positive and negative symptoms of schizophrenia, with a low propensity to induce tardive dyskinesia (TD). Compared with typical antipsychotics, it has a greater affinity for dopamine D4 than D2 receptors and additional action on serotonin 5-HT(2A) receptors. Due to its weak D(2) blocking...

Schizophrenia, bipolar disorder, and attention deficit/hyperactivity disorder (ADHD) present abnormalities in emotion processing. A previous study showed that the spontaneously hypertensive rats (SHR), a putative animal model of ADHD, present reduced contextual fear conditioning (CFC). The aim of the present study was to characterize the deficit in CFC presented by SHR. Adult male normotensive ...

usually centres on improving dopaminergic func tion in the nigro-striatal pathways. Levo-dopa and selegiline increase the amount of synaptic dopamine available; apomorphine, bromocriptlne and pergolide are agonists at dopamine receptors. Symptoms may also be improved by redressing the balance of dopaminergic and cholinergic activity. Benzhexol, procyclidine and orphenadrine, among others, are a...

usually centres on improving dopaminergic func tion in the nigro-striatal pathways. Levo-dopa and selegiline increase the amount of synaptic dopamine available; apomorphine, bromocriptlne and pergolide are agonists at dopamine receptors. Symptoms may also be improved by redressing the balance of dopaminergic and cholinergic activity. Benzhexol, procyclidine and orphenadrine, among others, are a...

Comparison of C.S. F. H. V. A and 5-HIAA levels of 20 Schizophrenics and 9 non-schizophrenic controls revealed no statistically significant difference between HVA levels but the 5-HIAA levels were significantly less in Schizophrenics (p < 0.05) than in controls. The significance of these findings is discussed.

Antiemetic effects of serotonin 5-HT3 receptor antagonists (ICS205-930, zacopride, BRL43694, GR38032F) were investigated in Suncus murinus. Veratrine, nicotine, copper sulfate, cisplatin, cyclophosphamide and motion sickness were used as emetic stimuli. Serotonin 5-HT3 receptor antagonists did not inhibit emetic responses to veratrine, nicotine, copper sulfate and motion sickness. However, cisp...

Schizophrenia and schizophrenia-like symptoms induced by the dopamine agonists and N-methyl-D aspartate type glutamate receptor antagonists occur only after the adolescent period. Similarly, animal models of schizophrenia by these drugs are also induced after the critical period around postnatal week three. Based upon the development-dependent onsets of these psychotomimetic effects, by using a...

Latent inhibition (LI) is demonstrated when a previously unattended/inconsequential stimulus is less effective in a new learning situation than a novel stimulus. In rats and humans, LI is reduced by dopamine agonists and increased by dopamine antagonists. In addition, LI is attenuated in actively psychotic schizophrenia patients, thus conferring strong predictive validity to the animal LI prepa...

Chemotherapy-induced nausea and vomiting (CINV) affects many cancer patients and has a great influence on quality of life. CINV involves coordination of several organs of the gastrointestinal tract, the peripheral and central nervous systems. Many neurotransmitters are involved in this process, and the predominant receptors are serotonin, neurokinin-1 and dopamine receptors. Risk factors for CI...

Several studies have demonstrated that systemically administered N-methyl-d-aspartate (NMDA) receptor antagonists increase serotonin (5-HT) and glutamate release in the medial prefrontal cortex (mPFC). Previously we showed that the perfusion of clozapine in the mPFC prevented the MK-801-induced increase in extracellular glutamate and 5-HT whereas haloperidol blocked only the effect of MK-801 on...