Responses of dopaminergic, serotonergic and noradrenergic networks to acute levo-tetrahydropalmatine administration in naive rats detected at 9.4 T

Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Magnetic Resonance Imaging (Impact Factor: 2.09). 11/2011; 30(2):261-70. DOI: 10.1016/j.mri.2011.09.006
Source: PubMed


The aim of this study was to understand the neuropharmacological characteristics of levo-tetrahydropalmatine (l-THP), a recently found potential treatment for drug addiction, and discover its neural correlates and sites of action.
High-field pharmacological magnetic resonance imaging (phMRI) was used to detect activation induced by acute l-THP administration in the naïve rat brain at dose levels of 5, 10, 20 and 40 mg/kg.
Interestingly, the pharmacological profile of l-THP selectively binds to the receptors of the dopaminergic, serotonergic and noradrenergic systems. Using the phMRI method, it was demonstrated that l-THP selectively activated the key brain regions of the dopaminergic, serotonergic and noradrenergic systems in a dose-dependent manner.
Numerous studies suggest a critical role of monoamines in the behavioral, pharmacological and addictive properties of psychostimulants. It is suggested that l-THP holds great potential to be a therapeutic medication for drug addiction.

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