The effect of testosterone upon methamphetamine neurotoxicity of the nigrostriatal dopaminergic system.
Animals; Corpus Striatum/drug effects/*metabolism; Dopamine/*metabolism; Drug Implants; Female; Male; Methamphetamine/*toxicity; Mice; Neuroprotective Agents/pharmacology; Neurotoxins/*toxicity; Orchiectomy; Ovariectomy; Potassium/pharmacology; Substantia Nigra/drug effects/*metabolism; Testosterone/administration & dosage/*pharmacology
The gonadal steroid hormone estrogen (E) can function as a neuroprotectant of nigrostriatal dopaminergic (NSDA) neurotoxicity, however, there exists very limited information on the role of testosterone (T) in this capacity. In the present report, the effects of T on methamphetamine (MA) induced neurotoxicity of the NSDA system were examined in gonadectomized female and male CD-1 mice. In Experiment 1, striatal dopamine (DA) concentrations and output from T-treated ovariectomized mice were not significantly different from that of non-T-treated mice following MA. These results suggest that T is not functioning as a modulator of MA-induced NSDA neurotoxicity in ovariectomized CD-1 mice. In Experiment 2, there were no significant differences in DA concentrations or output among
Gao X; Dluzen D E
Brain research
2001
2001-02
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/s0006-8993(00)03221-2" target="_blank" rel="noreferrer noopener">10.1016/s0006-8993(00)03221-2</a>
Testosterone modulation of striatal dopamine output in orchidectomized mice.
Adrenergic Uptake Inhibitors/pharmacology; Animals; Corpus Striatum/drug effects/*metabolism; Dopamine/*metabolism/pharmacology; Male; Mice; Neural Pathways/drug effects/*metabolism; Orchiectomy; Potassium Chloride/pharmacology; Presynaptic Terminals/drug effects/metabolism; Reserpine/pharmacology; Sex Characteristics; Substantia Nigra/drug effects/*metabolism; Synaptic Transmission/drug effects/physiology; Synaptic Vesicles/drug effects/metabolism; Testosterone/*metabolism; Vesicular Monoamine Transport Proteins/drug effects/metabolism
Three experiments are presented in which dopamine (DA) responses from superfused striatal tissue of orchidectomized (ORCH) mice treated or not with testosterone (T) are compared. In experiment 1, potassium-stimulated DA output was significantly greater in ORCH vs. ORCH+T mice. This profile was reversed when reserpine was infused in experiment 2, with DA output being significantly greater in ORCH+T vs. ORCH mice. In experiment 3, the amount of DA recovered following infusion of DA indicated no statistically significant differences in DA recoveries between ORCH and ORCH+T mice as tested in this paradigm. The findings that both potassium- and reserpine-induced DA responses are altered significantly by T suggests that one potential site of T action might involve the storage/uptake of DA within the vesicles of these neurons. Such results have important implications with regard to understanding the sex differences that are present in nigrostriatal dopaminergic function within health and diseased states.
Shemisa Kamal; Kunnathur Vidhya; Liu Bin; Salvaterra Ty J; Dluzen Dean E
Synapse (New York, N.Y.)
2006
2006-10
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1002/syn.20309" target="_blank" rel="noreferrer noopener">10.1002/syn.20309</a>