Differences in reserpine-induced striatal dopamine output and content between female and male mice: implications for sex differences in vesicular monoamine transporter 2 function.
*Sex Characteristics; Adrenergic Uptake Inhibitors/*pharmacology; Animals; Chromatography; Corpus Striatum/drug effects/*metabolism; Dopamine/*metabolism; Female; High Pressure Liquid; Male; Mice; Orchiectomy; Ovariectomy; Reserpine/*pharmacology; Vesicular Monoamine Transport Proteins/*metabolism
In this report a series of six in vitro experiments in which reserpine-evoked dopamine output and two in vivo experiments in which the effects of reserpine injections upon dopamine content from striatal tissue of female and male mice were performed as a means to assess possible sex differences in vesicular monoamine transporter 2 (VMAT2) function. Significantly greater amounts of dopamine were obtained from striatal tissue of female mice in response to either a brief (experiment 1) or continuous (experiment 2) infusion of reserpine. Similarly, reserpine-evoked dopamine output from striatal tissue of gonadectomized females was significantly greater that that of gonadectomized males (experiment 3). When reserpine-evoked dopamine responses were compared directly between intact versus gonadectomized females (experiment 4) or males (experiment 5) no statistically significant differences were obtained. Finally, comparisons of gonadectomized females treated or not with estrogen revealed no statistically significant differences in reserpine-evoked dopamine output (experiment 6). Injections of reserpine produced significantly greater depletions of striatal dopamine content within intact female versus male mice (experiment 7). Dopamine contents of gonadectomized females treated or not with estrogen did not differ following treatment with reserpine, but were significantly greater than that of gonadectomized males (experiment 8). Taken together, these results show that female striatal tissue is more responsive to reserpine-evoked dopamine output, and this sex difference appears to be estrogen independent. Similarly, the dopamine depleting effects of reserpine are greater in intact female mice, however, gonadectomy reverses this effect in an estrogen independent manner. The data suggest that female mice may have a greater amount/activity of VMAT2 function as revealed by the increased responsiveness to the VMAT2 blocking drug, reserpine. Such differences in VMAT2 function may be related to the gender differences observed in conditions like Parkinson's disease and drug addiction.
Dluzen D E; Bhatt S; McDermott J L
Neuroscience
2008
2008-07
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/j.neuroscience.2008.04.051" target="_blank" rel="noreferrer noopener">10.1016/j.neuroscience.2008.04.051</a>
The effect of reserpine treatment in vivo upon L-dopa and amphetamine evoked dopamine and DOPAC efflux in vitro from the corpus striatum of male rats.
3; 4-Dihydroxyphenylacetic Acid/*metabolism; Amphetamine/*pharmacology; Animals; Cell Compartmentation; Corpus Striatum/*drug effects/metabolism; Dopamine/*metabolism; Drug Interactions; Levodopa/*pharmacology; Male; Rats; Research Design; Reserpine/*pharmacology; Secretory Rate/drug effects; Sprague-Dawley
In the present experiment we tested the effects of L-DOPA and amphetamine upon dopamine and DOPAC efflux in vitro from superfused corpus striatal tissue fragments of male rats who had been pretreated with reserpine. Male rats were treated with reserpine (5 mg/kg) or its vehicle at 24 hours prior to sacrifice and superfusion of the corpus striatum. Two different modes of L-DOPA (5 microM) and amphetamine (10 microM) stimulation, a brief 10-minute and a continuous
Dluzen D E; Liu B
Journal of neural transmission. General section
1994
1994
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/10.1007/bf01271567" target="_blank" rel="noreferrer noopener">10.1007/bf01271567</a>
L-dopa infusion mode differentially affects corpus striatal dopamine efflux in the presence of reserpine.
Amphetamine/pharmacology; Animals; Chromatography; Corpus Striatum/*drug effects/metabolism; Dopamine/*metabolism; High Pressure Liquid; Infusions; Intravenous; Levodopa/*pharmacology; Male; Potassium/pharmacology; Rats; Reserpine/*pharmacology; Sprague-Dawley
In the present experiment we tested the effects of L-DOPA upon dopamine (DA) efflux in vitro from superfused corpus striatal tissue fragments in medium containing reserpine. The purposes of this experiment were first, to evaluate the effects of differing infusion modes of L-DOPA upon DA efflux under conditions in which DA storage capacity has been diminished, and second, to compare this L-DOPA stimulated DA efflux with that of other putative DA secretagogues such as amphetamine and potassium. No differences were obtained in stimulated DA efflux between superfusions performed in the presence or absence of reserpine (10 microM) in the medium when L-DOPA (5 microM) was infused in a continuous (70 minute) mode during the superfusion. In contrast, a continuous infusion of either amphetamine (10 microM) or high potassium (30 mM) resulted in significantly greater stimulated DA efflux in superfusions performed with reserpine in the medium. In addition, when L-DOPA (5 microM) was administered for a brief
Dluzen D E; Kratko F T Jr
Journal of neural transmission. General section
1992
1905-6
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/10.1007/bf01250672" target="_blank" rel="noreferrer noopener">10.1007/bf01250672</a>