R. Robert Holson

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The depletion of striatal dopamine (DA) that can occur after methamphetamine (METH) administration has been linked to METH-induced hyperthermia. The relationship between METH-induced hyperthermia, neurotoxicity (striatal DA depletions) and compounds that protect against METH neurotoxicity was further investigated in this study. Typically, rats exposed to(More)
Recently we have reported that methamphetamine (METH) neurotoxicity in rats depends on the environmental temperature. Here, we evaluate whether a cold environment (4 degrees C) or drugs which chloride and glutamate ion channel function block METH neurotoxicity in mice. Adult male CD mice received METH i.p. (4 x 10 mg/kg METH at 23 degrees C along with(More)
Developmental studies often assess the effect of treatment of the pregnant mother on offspring. The use of multiparous species such as rats and mice in such studies creates a special set of design and analysis problems. These arise for two reasons. First, the availability of many offspring per litter tempts the experimenter to inflate sample size by(More)
When male rats were injected four times (once every 2 hr) with 5 mg/kg methamphetamine (METH) at an environmental temperature of 23 degrees C, transient changes occurred in the levels of striatal dopamine (DA) and the regulation of striatal DA release. Striatal DA levels were minimally affected 1 day after METH treatment, but 3 days after METH treatment,(More)
The data from developmental neurotoxicity (DNT) guideline studies present a number of challenges for statistical design and analysis. The importance of specifying the planned statistical analyses a priori cannot be overestimated. A review of datasets submitted to the US Environmental Protection Agency revealed several inadequate approaches, including issues(More)
Repeated administration of amphetamine to adult rats results in enhanced behavioral responses to subsequent amphetamine exposure. These experiments were designed to determine the earliest age at which behavioral sensitization to amphetamine could be detected. Rats from both sexes (n=6–8/group) at ages of 1, 7, 21 or 49 postnatal days (PNDs) were injected(More)
Extracellular levels of d-amphetamine (AMPH) in caudate/putamen were determined using microdialysis and HPLC quantitation after s.c. doses that produced increased motor activity (1 mg/kg), stereotypic behavior (2.5 mg/kg) or dopamine depletion in the caudate/putamen (4 x 5 mg/kg). In 6-mo-old rats exposed to neurotoxic doses of AMPH sulfate (4 x 5 mg/kg in(More)
Early reports of enhanced behavioral reactivity in isolation-reared rats attributed this syndrome to "isolation stress." In the studies reported here, this "isolation stress syndrome" was reliably obtained in adult rats reared from weaning in individual hanging metal cages. Such isolates showed behavioral and adrenocortical symptoms of profound fear during(More)
MDMA (methylenedioxymethamphetamine) is a recreational drug of abuse known as "Ecstasy" which markedly decreases regional brain serotonin (5-HT) content and produces 5-HT nerve terminal degeneration in forebrain areas of the rat. In order to determine the acute and chronic behavioral effects of MDMA, adult rats were given MDMA at 0, 5 or 10 mg/kg, po for 4(More)
Extracellular levels of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and serotonin (5-HT) were assayed in the caudate of freely moving rats using microdialysis and high performance liquid chromatography with electrochemical detection (HPLC-EC) to detect changes in their release.(More)