Edward D French

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• French, E. D., Janezic, E. M., Uppalapati, S., Nagl, S., Contreras, M., & Fellous, J. (2016). Beneficial effects of chronic oxytocin administration and social co-housing in a rodent model of post-traumatic stress disorder. Behavioural Pharmacology, 1, 1-13.
• French, E. D., Corral-Frias, N., & Fellous, J. (2012). Involvement of the ventral tegmental area in a rodent model of post-traumatic stress disorder. Neuropsychopharmacology, 38, 350-363.
• French, E., Gerdeman, G. L., Schechter, J. B., & French, E. D. (2008). Context-specific reversal of cocaine sensitization by the CB1 cannabinoid receptor antagonist rimonabant. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 33(11).
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  The CB(1) cannabinoid receptor is implicated in the rewarding properties of many drugs of abuse, including cocaine. While CB(1) receptor involvement in the acute rewarding properties of cocaine is controversial, CB(1) antagonists such as SR141716 (rimonabant) have clearly been found to prevent cue- and cocaine-elicited reinstatement of cocaine self-administration in rodents. Here we demonstrate the novel involvement of CB(1) receptors in the maintenance of behavioral sensitization to cocaine in C57BL/6 mice. Consistent with previous reports, the induction of locomotor sensitization following repeated daily cocaine was not prevented by systemic pretreatment of either rimonabant, Delta(9)-tetrahydrocannabinol (THC), or a 1:1 mixture of THC and cannabidiol (CBD). In contrast, established cocaine sensitization was markedly disrupted following subchronic treatment with rimonabant alone. This effect was notably context-dependent, in that rimonabant did not diminish established cocaine sensitization if delivered in the home cage, but only if the rimonabant-injected mice were exposed to activity chambers previously paired with cocaine. These findings are consistent with CB(1) receptor involvement in conditioned cocaine-seeking behaviors, and further suggest that endocannabinoid (eCB)-mediated synaptic plasticity may act specifically within drug-paired environments to maintain cocaine-directed behavioral responses.
• French, E., Riegel, A. C., Zapata, A., Shippenberg, T. S., & French, E. D. (2007). The abused inhalant toluene increases dopamine release in the nucleus accumbens by directly stimulating ventral tegmental area neurons. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 32(7).
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  Recreational abuse of toluene-containing volatile inhalants by adolescents is a significant public health problem. The mechanisms underlying the abuse potential of such substances remain unclear, but could involve increased activity in mesoaccumbal dopamine (DA) afferents innervating the nucleus accumbens (ACB). Here, using in vitro electrophysiology, we show that application of behaviorally relevant concentrations of toluene directly stimulates DA neurons in the ventral tegmental area (VTA), but not surrounding midbrain regions. Toluene stimulation of VTA neurons persists when synaptic transmission is reduced. Moreover, unlike non-DA neurons, the magnitude of VTA DA neuron firing does not decline during longer exposures designed to emulate 'huffing'. Using dual-probe in vivo microdialysis, we show that perfusion of toluene directly into the VTA increases DA concentrations in the VTA (somatodendritic release) and its terminal projection site, the ACB. These results provide the first demonstration that even brief exposure to toluene increases action potential drive onto mesoaccumbal VTA DA neurons, thereby enhancing DA release in the ACB. The finding that toluene stimulates mesoaccumbal neurotransmission by activating VTA DA neurons directly (independently of transynaptic inputs) provide insights into the neural substrates that may contribute to the initiation and pathophysiology of toluene abuse.
• French, E., & French, E. D. (2004). Academic pharmacologists: confronting new challenges in educational programs of graduate and health care professionals. The Journal of pharmacology and experimental therapeutics, 309(2).
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  Pharmacologists belong to a special fraternity, one whose members love to study drugs, even though we may have highly individualized viewpoints about what aspect of drug action delights our intellectual curiosities. Still it is this passion to understand everything about a drug that drives our need to uncover the essence of a chemical's effect on living cells and tissues, and ultimately how it exerts its therapeutic benefits. In this sense, pharmacology is a discipline key to the health sciences in that it bridges basic and clinical endeavors, as well as between professional practices.
• French, E., Riegel, A. C., & French, E. D. (2002). Abused inhalants and central reward pathways: electrophysiological and behavioral studies in the rat. Annals of the New York Academy of Sciences, 965.
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  Inhalant abuse remains a significant health problem among the younger segment of society. In fact, the use of inhalants in this population trails only that of nicotine, alcohol, and marijuana. Toluene is a common ingredient in many of the substances sought out for inhalation abuse, apparently for its euphorigenic and hallucinogenic effects. Because drugs of abuse share the common property of altering the activity of mesolimbic dopamine neurons, it is reasonable to suspect that toluene-induced changes in this CNS pathway may underlie its abuse potential. Here we will provide in vivo and in vitro electrophysiological data and behavioral evidence linking toluene exposure in rats to activation of mesolimbic dopamine neurons. Exposure of rats to 11,000 ppm of inhaled toluene produced time-dependent activation of dopamine neurons within the midbrain ventral tegmental area (VTA). In the rat brain slice preparation, perfusion with toluene (23-822 microM) also evoked an increase in activity of both dopamine and nondopamine neurons within the VTA. These excitatory effects could not be found in adjacent non-VTA nuclei, nor were they sensitive to the glutamate antagonists CGS19755 or CNQX. In behavioral studies, systemic administration of toluene produced a dose-dependent locomotor hyperactivity that was attenuated by either pretreatment with the D2 dopamine receptor antagonist remoxipride or by 6-hydroxydopamine lesions of the nucleus accumbens. These findings show that toluene can activate dopamine neurons within the mesolimbic reward pathway, an effect that may underlie the abuse potential of inhaled substances containing toluene.