Effects of histamine H1-receptor antagonists on L-dopa-induced behavioral excitement were examined in mice to confirm behaviorally the inhibition of dopamine uptake by these compounds. L-Dopa (100-300 mg/kg, s.c.) combined with pargyline hydrochloride (80 mg/kg, i.p.) caused a dose-dependent behavioral excitement. The marked excitement induced by L-dopa (300 mg/kg) plus pargyline was significan...

Adenosine A2A receptor (A2AR)-dopamine D2 receptor (D2R) heteromers are key modulators of striatal neuronal function. It has been suggested that the psychostimulant effects of caffeine depend on its ability to block an allosteric modulation within the A2AR-D2R heteromer, by which adenosine decreases the affinity and intrinsic efficacy of dopamine at the D2R. We describe novel unsuspected allost...

S. Akhondzadeh , A. Safarcherati & H. Amini Psychiatric Research Centre, Roozbeh Hospital, Tehran University of Medical Sciences; Institute of Medicinal Plants, Tehran, Iran. Schizophrenia is a chronic progressive disease and it affects more than 1% of the population. The etiology of schizophrenia remains unknown in a majority of cases (Mohammadi and Akhondzadeh, 2001). There is a large amount ...

Recent pharmacological data suggest that a receptor-receptor interaction between adenosine A2 and dopamine D2 receptors in the brain underlies the behavioral effects of adenosine agonists and adenosine antagonists, such as caffeine and theophylline. According to this interaction, stimulation of A2 receptors inhibits and their blockade potentiates the effects of D2 receptor stimulation. Furtherm...

Stuttering is a disturbance in the normal fluency and time patterning of speech. Developmental stuttering (DS), with or without associated psychiatric illness, is the most common form and includes all cases with gradual onset in childhood that are not the result of acquired brain damage. Persistent developmental stuttering (PDS) is DS that has not undergone spontaneous or speech-therapy-induced...

antiemetics 5-Hydroxytryptamine type 3 receptor (5HT3) (serotonin) antagonists, corticosteroids and aprepitant are usually given once daily. However, for delayed emesis corticosteroids are given two times daily. Dopamine antagonists are given three or four times daily. For routine use oral doses are recommended [I, A]. Palonosetron is only available as an i.v. formulation. Substances of the sam...

Dopamine release in the nucleus accumbens (NAC) plays a crucial role in the action of various psychotropic and addictive drugs, such as antagonists of the N-methyl-D-aspartate subtype of the glutamate. Although both nitrous oxide and xenon are N-methyl-D-aspartate receptor antagonists, they differ in their potential for producing neuropsychological toxicity; therefore, we decided to examine the...

Drug discovery based on development of selective ligands for a specific target intended to modulate its activity and revert pathophysiological process is now recognized as too simplistic to design effective agent for complex multifactorial diseases, characterized by diverse physiological dysfunctions caused by deregulations of complex networks of proteins. Major challenge in modern drug discove...

Apoptosis has been identified as the primary cause of fetal alcohol spectrum disorder (FASD), and the development of methods to prevent and treat FASD have been based on the mechanisms of alcohol-induced apoptosis. The present study aimed to explore the effects of dopamine on alcohol‑induced neuronal apoptosis using whole‑mount cultures of rat retinas (postnatal day 7). Retinas were initially i...

Substantial evidence suggests that all commonly abused drugs act upon the brain reward circuitry to ultimately increase extracellular concentrations of the neurotransmitter dopamine in the nucleus accumbens and other forebrain areas. Many drugs of abuse appear to increase dopamine levels by dramatically increase the firing and bursting rates of dopamine neurons located in the ventral mesencepha...