A circadian clock modulates the functional organization of the Japanese quail retina. Under conditions of constant darkness, rods dominate electroretinogram (ERG) b-wave responses at night, and cones dominate them during the day, yielding a circadian rhythm in retinal sensitivity and rod-cone dominance. The activity of tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, also e...

BACKGROUND/OBJECTIVE In the present study, the effect of acute lead exposure in the presence and absence of dopamine or alpha (alpha)-adrenoceptor agents on contractile response of rat isolated thoracic aorta was studied. METHODS Male Wistar rats were used in all experiments. Thoracic aorta was carefully removed, cleaned, and cut into 2-mm thick rings. The rings were mounted for measurement o...

The role of dopamine as a vulnerability factor and a toxic agent in Parkinson's disease (PD) is still controversial, yet the presumed dopamine toxicity is partly responsible for the "DOPA-sparing" clinical practice that avoids using L-3,4-dihydroxyphenylalanine (L-DOPA), a dopamine precursor, in early PD. There is a lack of studies on animal models that directly isolate dopamine as one determin...

Drug addiction is characterised by compulsive, uncontrollable drug use irrespective of its negative consequences. It has been recognised as a chronic disease with high possibility of relapse inflicting far-reaching psychological and physical damage on sufferers. 2 Over the past decade, the prevalence of illicit drug use has been stable at around 0.5% of the population globally but it varies by ...

Background: Feeding behavior is regulated by a complex network which interacts via diverse signals from central and peripheral tissues. It is known dopaminergic and glutamatergic systems have crucial role on food intake regulation but scarce reports exist on their interaction in appetite regulation in broilers. OBJECTIVES: The present study was designed to examine the role of glutamatergic syst...

Abstract The treatment of neuropsychiatric and neurodegenerative disorders such as depression Parkinson’s disease represent significant challenges in healthcare. Enzymes that metabolise neurotransmitter amines are important drug targets for these inhibitors enzymes have played key roles therapeutic agents. For example, monoamine oxidase (MAO) A been used decades antidepressant agents act by inh...

Therapeutic strategies in Parkinson's disease (PD) provide control of motor (nigral) and nonmotor (extranigral) symptoms. Nigral dopamine-related signs and symptoms are addressed by supplementation or substitution of cerebral dopamine, and extranigral nondopamine-related symptoms are treated by addressing specific autonomic, neuropsychiatric and sleep dysfunctions. However, the ultimate goal in...

High-dose administrations of amphetamine, methamphetamine, cathinone, methcathinone or methylenedioxymethamphetamine rapidly decrease dopamine and serotonin transporter function in vivo, as assessed in striatal synaptosomes obtained from drug-treated rats. In contrast, high-dose injections of fenfluramine, cocaine or methylphenidate had little or no effect on the activity of these transporters....

Parkinson's disease is a progressive neurodegenerative dysfunction characterized by the loss of pigmented dopaminergic neurons of the nigrostriatal system with a consequent dopamine decrease. The reduction of dopamine levels produces neuronal damage, depigmentation of the substantia nigra, and the presence of intracellular inclusions in dopaminergic neurons. Treatments for Parkinson's disease a...

Norepinephrine (noradrenaline) and dopamine are commonly used first-line vasopressor agents in the treatment of patients with septic shock. Recently increasing interest has focused on whether one or other of these agents is superior in terms of improving outcome. Studies have looked particularly at the possible local effects of the vasopressors on splanchnic circulation, because evidence sugges...