Background: Voltage-gated calcium channels (VGCCs) in rat neurohypophysial terminals exhibit molecular tolerance to alcohol, including desensitization to the drug and increased current density, after 3 weeks of alcohol drinking. Moreover, after this time, terminals from drinking rats exhibit diminished alcohol inhibition of vasopressin (AVP) release.
Methods: We took advantage of organotypic cultures (explants) of the hypothalamo-neurohypophysial system (HNS) to extend our analysis of molecular tolerance to 2 classes of the VGCC.
Tolerance represents a critical component of addiction. The large-conductance calcium- and voltage-activated potassium channel (BK) is a well-established alcohol target, and an important element in behavioral and molecular alcohol tolerance. We tested whether microRNA, a newly discovered class of gene expression regulators, plays a role in the development of tolerance.
View Article and Find Full Text PDFTolerance is an important element of drug addiction and provides a model for understanding neuronal plasticity. The hypothalamic-neurohypophysial system (HNS) is an established preparation in which to study the actions of alcohol. Acute application of alcohol to the rat neurohypophysis potentiates large-conductance calcium-sensitive potassium channels (BK), contributing to inhibition of hormone secretion.
View Article and Find Full Text PDFAlcohol is an addictive drug that targets a variety of ion channels and receptors. To address whether the effects of alcohol are compartment specific (soma vs dendrite), we examined the effects of ethanol (EtOH) on large-conductance calcium-activated potassium channels (BK) in cell bodies and dendrites of freshly isolated neurons from the rat nucleus accumbens (NAcc), a region known to be critical for the development of addiction. Compartment-specific drug action was indeed observed.
View Article and Find Full Text PDFIn this study, we sought to characterize the effects of focal GABA(A) receptor antagonism on spontaneous and evoked activity in dorsal horn neurons of the alpha-chloralose anesthetized cat. Bicuculline (0.5, 1.
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