Modulatory effects of testosterone on
Male; Animals; Mice; Species Specificity; Reference Values; Dopamine/*metabolism; Corpus Striatum/drug effects/*metabolism; Orchiectomy; Drug Implants; Testosterone/administration & dosage/*pharmacology; Neurotoxins/antagonists & inhibitors/*toxicity; *MPTP Poisoning; Levodopa/pharmacology; Inbred Strains; Inbred C57BL; 3; 1-Methyl-4-phenyl-1; 2; Parkinson Disease; 6-tetrahydropyridine/antagonists & inhibitors; Secondary/chemically induced/*physiopathology
In this experiment, we examined the modulatory effects of testosterone on the parkinsonism-inducing drug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in two strains of mice. Orchidectomized male CD-1 and C57/B1 mice were implanted with either empty Silastic capsules or capsules containing testosterone and subsequently treated with MPTP. A small area of the corpus striatum was removed for determination of dopamine (DA) content, whereas the remainder was superfused and used to measure L-DOPA (5 microM)-evoked DA release. In animals treated with MPTP, L-DOPA-evoked DA release was reduced significantly in CD-1 mice, but not in C57/B1 mice, treated with testosterone. No differences in L-DOPA-stimulated DA release between MPTP-versus vehicle-treated mice was observed in either the CD-1 or C57/B1 mice receiving empty Silastic capsules. Corpus striatum DA contents were more severely depleted in the MPTP-sensitive C57/B1 versus the CD-1 mouse strain irrespective of hormone treatment. These results confirm previous results demonstrating differences in these two mouse strains in response to the neurotoxic effects of MPTP upon corpus striatum DA content. More interestingly, they show an important differential modulatory effect of testosterone upon
Dluzen D; Jain R; Liu B
Journal of neurochemistry
1994
1994-01
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
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>