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Autism is a severe behavioral disorder characterized by pervasive impairments in social interactions, deficits in verbal and nonverbal communication, and stereotyped, repetitive patterns of behaviors and interests. Recently, a new rodent model of autism was created by exposure of rat fetuses to valproic acid (VPA) on the 12.5th day of gestation (VPA rats).(More)
The advance in our understanding of the biogenesis of various endogenous opioid peptides, their anatomical distribution, and the characteristics of the multiple receptors with which they interact open a new avenue for understanding the role of opioid peptide systems in chronic pain. The main groups of opioid peptides: enkephalins, dynorphins and(More)
Autism is a severe behavioral disorder characterized by pervasive impairments in social interactions, deficits in verbal and non-verbal communication, and stereotyped behaviors, with a four times higher incidence in boys than in girls. The core symptoms are frequently accompanied by a spectrum of neurobehavioral and immunological derangements, including:(More)
A minority of individuals experiencing traumatic events develop anxiety disorders. The reason for the lack of correspondence between the prevalence of exposure to psychological trauma and the development of anxiety is unknown. Extracellular proteolysis contributes to fear-associated responses by facilitating neuronal plasticity at the neuron-matrix(More)
Environmental enrichment has been repeatedly shown to affect multiple aspects of brain function, and is known to improve cognitive, behavioral, and histopathological outcome after brain injuries. The purpose of the present experiments was to determine the effect of an enriched environment on behavioral aberrations observed in male rats exposed to valproic(More)
Exogenous opioids can produce localized opioid receptor-mediated antinociception in peripheral inflamed tissue. Previous studies show that activation of endogenous opioids by a cold water swim in rats with hind paw inflammation results in a similar local antinociceptive effect but suggest that pituitary-adrenal opioid pools are not directly involved in(More)
Our previous studies indicate that endogenous opioids (primarily beta-endorphin) released during stressful stimuli can interact with peripheral opioid receptors to inhibit nociception in inflamed tissue of rats. This study sought to localize opioid precursor mRNAs and opioid peptides deriving therefrom in inflamed tissue, identify opioid containing cells(More)
We studied spinal analgesic and antiallodynic effects of endomorphin-1 and endomorphin-2 administered i.t. in comparison with Tyr-D-Ala-Gly-MePhe-Gly-ol (DAMGO) or morphine, during acute, inflammatory and neuropathic pain in rats chronically implanted with intrathecal cannulas. Endomorphin-1 and endomorphin-2 (2.5, 5, 10 microg i.t.) increased the(More)
The effect of the nitric oxide (NO) synthase inhibitor L-NG-nitroarginine methyl ester (L-NAME, 5-20 mg/kg i.p.) and NG-nitro-L-arginine (NO2Arg, 5-20 mg/kg i.p.) on morphine-induced analgesia, as well as on morphine induced tolerance and dependence was examined in male albino Swiss mice. Neither acute nor repeated (for 5 days) administration of the nitric(More)
It has been suggested that behavioral aberrations observed in autism could be the result of dysfunction of the neuroregulatory role performed by the endogenous opioid peptides. Many of those aberrations have been recently modeled in rats exposed to valproic acid (VPA) on the 12th day of gestation (VPA rats). The aim of the present study was to elucidate(More)