In vitro binding assays using (3)H nisoxetine and (3)H WIN 35,428 reveal selective effects of gonadectomy and hormone replacement in adult male rats on norepinephrine but not dopamine transporter sites in the cerebral cortex.
Abstract
The prefrontal cortices mediate cognitive functions that critically depend on local dopamine levels. In male rats, many prefrontal tasks where performance is disrupted by changes in dopamine signaling are also impaired by gonadectomy, a manipulation that increases cortical dopamine concentration, prefrontal dopamine axon density and possibly extracellular prefrontal dopamine levels as well. Because these actions could be responsible for the impairing effects of gonadectomy on prefrontal function, the question of how they might arise comes to the fore. Accordingly, the present studies asked whether dopamine levels might be increased via a hormone sensitivity of transporter-mediated dopamine uptake. Specifically, (3)H WIN 35,428 and (3)H nisoxetine, ligands selective for the dopamine (DAT)- and norepinephrine transporter (NET) respectively, were used in in vitro binding assays to ask whether gonadectomy altered transporter affinity (Kd) and/or binding site number (Bmax) in prefrontal cortex, sensorimotor cortex and/or caudate. Assays performed on tissues dissected from sham-operated, gonadectomized and gonadectomized rats supplemented with testosterone propionate or estradiol for 4 or 28 days revealed no significant group differe...Continue Reading
References
Development of the ability to use recall to guide action, as indicated by infants' performance on AB
Hyperlocomotion and indifference to cocaine and amphetamine in mice lacking the dopamine transporter
Relationships among dopamine transporter affinities and cocaine-like discriminative-stimulus effects
Citations
Related Concepts
Related Feeds
Basal Ganglia
Basal Ganglia are a group of subcortical nuclei in the brain associated with control of voluntary motor movements, procedural and habit learning, emotion, and cognition. Here is the latest research.