Administration of a single high dose of methamphetamine (METH) causes a rapid and reversible decrease in the activity of the tryptophan hydroxylase (TPH), the rate-limiting enzyme in the synthesis of 5-hydroxytryptamine. This effect can be reversed completely by exposing the METH-impaired enzyme to a reducing environment, which suggests that the decrease in TPH activity is a reversible oxidativ...

The maternal separation (MS) paradigm is an animal model of early life stress. Animals subjected to MS during the first 2 weeks of life display altered behavioral and neuroendocrinological stress responses as adults. MS also produces altered responsiveness to and self-administration (SA) of various drugs of abuse including cocaine, ethanol, and amphetamine. However, no studies have yet examined...

Methamphetamine (Meth) users report having heightened sexual pleasure, numerous sexual partners, and engaging in unprotected sex due to loss of inhibitory control. This compulsive sexual behavior contributes to increased prevalence of sexually transmitted infections, but the neural basis for this is unknown. We previously established a paradigm for compulsive sexual behavior in male rats in whi...

effects of intra-central amygdala administration of l-arginine, a nitric oxide precursor, and ng-nitro-l-arginine methyl-ester (l name), a nitric oxide synthase inhibitor, on the morphine-induced sensitization and also on the expression of morphine-induced place conditioning in rats were studied. subcutaneous (s.c.) administration of morphine (2.5, 5 and 7.5 mg/kg) induced place conditioning. r...

Sensitization of vagal lung C fibers has been postulated to contribute to the development of asthma, but support for this notion is still lacking. We investigated the characteristics and function of pulmonary C fibers (PCFs) in ovalbumin (OVA)-sensitized Brown Norway rats, an established animal model of asthma. Rats were sensitized with intraperitoneal injection of OVA or were treated with sali...

The effects of Ocimum basilicum (O. basilicum) and its constituent, rosmarinic acid, on total and differential blood WBC, serum levels of NO2, NO3, MDA, thiol, SOD and CAT in sensitized rats were examined. The study was performed in control animals (group C) and eight groups of sensitized rats to ovalbumin which were given drinking water alone (group S), drinking water containing three concentr...

High-dose methamphetamine (METH) causes damage to the dopamine and serotonin neurons in the brains of laboratory animals. The purpose of this report was to determine the long-term consequences of high-dose METH treatment on behavior and neurochemistry. Rats were trained on the differential reinforcement of low-rate 72-s (DRL 72-s) schedule of reinforcement. Twelve weeks after training began (ag...

The reward is a positive behavioural response to the pleasant stimuli that can be induced by drugs, such as psychostimulants. Furthermore, diabetes mellitus is a chronic disease that many people throughout the world suffer from. Methamphetamine (METH), as a psychostimulant, engages the dopaminergic system in the reward circuitry and the synapses of dopaminergic terminals can be modified by insu...

Objectives: In previous studies the therapeutic effects of Nigella sativa have been demonstrated on asthmatic animals. In the present study, the preventive effect of single dose of alpha-hederin, its active constituent, has been evaluated on lung inflammation and some inflammatory mediators in lungs of ovalbumin sensitized rat in order to elicit its mechanism. Materials and methods: Forty rats ...

Administration of a high-dose regimen of methamphetamine (METH) rapidly and profoundly decreases plasmalemmal and vesicular dopamine (DA) transport in the striatum, as assessed in synaptosomes and purified vesicles, respectively. To determine whether these responses were common to other amphetamines of abuse, effects of methylenedioxymethamphetamine (MDMA) on the plasmalemmal DA transporter (DA...