Effect of the weaver mutation on the expression of dopamine membrane transporter, tyrosine hydroxylase and vesicular monoamine transporter in dopaminergic neurons of the substantia nigra and the ventral tegmental area

1996 ◽  
Vol 43 (1-2) ◽  
pp. 291-300 ◽  
Author(s):  
Christine Adelbrecht ◽  
Yves Agid ◽  
Rita Raisman-Vozari
Keyword(s):  
Tyrosine Hydroxylase ◽  
Substantia Nigra ◽  
Ventral Tegmental Area ◽  
Dopaminergic Neurons ◽  
Vesicular Monoamine Transporter ◽  
Membrane Transporter ◽  
Monoamine Transporter ◽  
Ventral Tegmental

scholarly journals Programming of Dopaminergic Neurons by Neonatal Sex Hormone Exposure: Effects on Dopamine Content and Tyrosine Hydroxylase Expression in Adult Male Rats

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Pedro Espinosa ◽  
Roxana A. Silva ◽  
Nicole K. Sanguinetti ◽  
Francisca C. Venegas ◽  
Raul Riquelme ◽  
...  
Keyword(s):  
Nucleus Accumbens ◽  
Tyrosine Hydroxylase ◽  
Substantia Nigra ◽  
Ventral Tegmental Area ◽  
Dopaminergic Neurons ◽  
Dopamine Release ◽  
Male Rats ◽  
Midbrain Dopaminergic Neurons ◽  
Dopamine Content ◽  
Ventral Tegmental

We sought to determine the long-term changes produced by neonatal sex hormone administration on the functioning of midbrain dopaminergic neurons in adult male rats. Sprague-Dawley rats were injected subcutaneously at postnatal day 1 and were assigned to the following experimental groups: TP (testosterone propionate of 1.0 mg/50 μL); DHT (dihydrotestosterone of 1.0 mg/50 μL); EV (estradiol valerate of 0.1 mg/50 μL); and control (sesame oil of 50 μL). At postnatal day 60, neurochemical studies were performed to determine dopamine content in substantia nigra-ventral tegmental area and dopamine release in nucleus accumbens. Molecular (mRNA expression of tyrosine hydroxylase) and cellular (tyrosine hydroxylase immunoreactivity) studies were also performed. We found increased dopamine content in substantia nigra-ventral tegmental area of TP and EV rats, in addition to increased dopamine release in nucleus accumbens. However, neonatal exposure to DHT, a nonaromatizable androgen, did not affect midbrain dopaminergic neurons. Correspondingly, compared to control rats, levels of tyrosine hydroxylase mRNA and protein were significantly increased in TP and EV rats but not in DHT rats, as determined by qPCR and immunohistochemistry, respectively. Our results suggest an estrogenic mechanism involving increased tyrosine hydroxylase expression, either by direct estrogenic action or by aromatization of testosterone to estradiol in substantia nigra-ventral tegmental area.

Cardiovascular depressor responses to stimulation of substantia nigra and ventral tegmental area

1997 ◽  
Vol 273 (6) ◽  
pp. H2549-H2557 ◽  
Author(s):  
Gilbert J. Kirouac ◽  
John Ciriello
Keyword(s):  
Substantia Nigra ◽  
Ventral Tegmental Area ◽  
Intravenous Administration ◽  
Dopaminergic Neurons ◽  
Cardiovascular Responses ◽  
Receptor Blocker ◽  
Transitional Region ◽  
Pars Lateralis ◽  
Ventral Tegmental ◽  
Stimulation Of

Experiments were done in α-chloralose-anesthetized, paralyzed, and artificially ventilated rats to investigate the effect ofl-glutamate (Glu) stimulation of the substantia nigra (SN) and ventral tegmental area (VTA) on arterial pressure (AP) and heart rate (HR). Glu stimulation of the SN pars compacta (SNC) elicited decreases in both mean AP (MAP; −18.9 ± 1.3 mmHg; n = 52) and HR (−26.1 ± 1.6 beats/min; n = 46) at 81% of the sites stimulated. On the other hand, stimulation of the SN pars lateralis or pars reticulata did not elicit cardiovascular responses. Stimulation of the adjacent VTA region elicited similar decreases in MAP (−18.0 ± 2.6 mmHg; n = 20) and HR (−25.4 ± 3.8 beats/min; n = 17) at ∼74% of the sites stimulated. Intravenous administration of the dopamine D2-receptor antagonist raclopride significantly attenuated both the MAP (70%) and the HR (54%) responses elicited by stimulation of the transitional region where the SNC merges with the lateral VTA (SNC-VTA region). Intravenous administration of the muscarinic receptor blocker atropine methyl bromide had no effect on the magnitude of the MAP and HR responses to stimulation of the SNC-VTA region, whereas administration of the nicotinic receptor blocker hexamethonium bromide significantly attenuated both the depressor and the bradycardic responses. These data suggest that dopaminergic neurons in the SNC-VTA region activate a central pathway that exerts cardiovascular depressor effects that are mediated by the inhibition of sympathetic vasoconstrictor fibers to the vasculature and cardioacceleratory fibers to the heart.

Intrastriatal implantation of interleukin-1

1994 ◽  
Vol 80 (3) ◽  
pp. 484-490 ◽  
Author(s):  
Jin Wang ◽  
Krzysztof S. Bankiewicz ◽  
Robert J. Plunkett ◽  
Edward H. Oldfield
Keyword(s):  
Substantia Nigra ◽  
Caudate Nucleus ◽  
Ventral Tegmental Area ◽  
Dopaminergic Neurons ◽  
Interleukin 1 ◽  
Behavioral Recovery ◽  
Content Type ◽  
Median Forebrain Bundle ◽  
Ventral Tegmental ◽  
Fine Print

✓ Intrastriatal implantation with dopaminergic or nondopaminergic tissue can elicit behavioral recovery in parkinsonian animals. Because in these animals, especially in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned monkeys, there are still considerable numbers of dopaminergic neurons left in the mesencephalon, implantation-induced trophic effects on host residual dopaminergic neurons have been suggested as a mechanism underlying the behavioral recovery. Gliosis around the graft is a universal finding in any implantation procedure and is probably mediated by interleukin-1 (IL-1); in addition, activated astrocytes secrete several neurotrophic factors in vitro. Therefore, the authors postulated that trophic effects from IL-1-induced gliosis may be a “final common pathway” for recovery in parkinsonian animals after implantation. Hemiparkinsonism was induced in rats by injection of 6-hydroxydopamine either directly into the substantia nigra or into the median forebrain bundle. The substantia nigra-lesioned rats showed complete depletion of dopaminergic neurons in the substantia nigra but sparing of those in the ventral tegmental area, whereas the median forebrain bundle-lesioned animals had depletion of dopaminergic cells in the substantia nigra and the ventral tegmental area. Polymer pellets containing either slow-released IL-1 alpha and beta or placebo pellets were implanted in the caudate nucleus on the lesioned side in both groups. The rats' rotational response to amphetamine was tested weekly for 8 weeks. Selective substantia nigra-lesioned rats with implantation of IL-1 pellets had a 45% reduction in amphetamine-induced rotation, whereas placebo-implanted substantia nigra-lesioned rats had a 14% reduction in rotation. In the median forebrain bundle-lesioned group, neither IL-1 nor placebo implantation elicited any effect on turning. Immunohistochemical staining for glial fibrillary acidic protein was markedly increased surrounding the IL-1 pellets compared to the placebo pellets. In the selective substantia nigra-lesioned rats with IL-1 pellets implanted in the caudate nucleus, a considerable number of tyrosine hydroxylase immunoreactive (TH-IR) fibers were observed in the medial and middle portions of the caudate nucleus. Fewer TH-IR fibers were seen in the rats with placebo-bearing pellets. These results suggest that neurotrophic activities mediated by IL-1 and reactive astrocytes might be a common path through which tissue trauma and some tissue transplants exert their beneficial effects in parkinsonian animals. Furthermore, most of the sprouted dopaminergic fibers induced by IL-1 in the caudate nucleus come from dopaminergic neurons in the ventral tegmental area.

On the properties of identified dopaminergic neurons in the mouse substantia nigra and ventral tegmental area

2016 ◽  
Vol 45 (1) ◽  
pp. 92-105 ◽  
Author(s):  
Paraskevi Krashia ◽  
Alessandro Martini ◽  
Annalisa Nobili ◽  
Daniela Aversa ◽  
Marcello D'Amelio ◽  
...  
Keyword(s):  
Substantia Nigra ◽  
Ventral Tegmental Area ◽  
Dopaminergic Neurons ◽  
Ventral Tegmental

scholarly journals Understanding the Mechanism of Antidepressant-Related Sexual Dysfunction: Inhibition of Tyrosine Hydroxylase in Dopaminergic Neurons after Treatment with Paroxetine but Not with Agomelatine in Male Rats

2019 ◽  
Vol 8 (2) ◽  
pp. 133 ◽  
Author(s):  
Yanira Santana ◽  
Angel Montejo ◽  
Javier Martín ◽  
Ginés LLorca ◽  
Gloria Bueno ◽  
...  
Keyword(s):  
Sexual Behavior ◽  
Tyrosine Hydroxylase ◽  
Sexual Dysfunction ◽  
Substantia Nigra ◽  
Ventral Tegmental Area ◽  
Median Eminence ◽  
Zona Incerta ◽  
Mediobasal Hypothalamus ◽  
Ventral Tegmental ◽  
Serotonergic Antidepressant

Antidepressant-related sexual dysfunction is a frequent adverse event caused by serotonergic activation that intensely affects quality of life and adherence in depressed patients. The dopamine system has multiple effects promoting sexual behavior, but no studies have been carried out to confirm dopaminergic changes involved in animal models after antidepressant use. Methods: The sexual behavior-related dopaminergic system in the rat was studied by comparing two different antidepressants and placebo for 28 days. The antidepressants used were paroxetine (a serotonergic antidepressant that causes highly frequent sexual dysfunction in humans) and agomelatine (a non-serotonergic antidepressant without associated sexual dysfunction). The tyrosine hydroxylase immunoreactivity (THI) in the substantia nigra pars compacta, the ventral tegmental area, the zona incerta, and the hypothalamic arcuate nucleus, as well as the dopaminergic projections to the striatum, hippocampus, cortex, and median eminence were analyzed. Results: The THI decreased significantly in the substantia nigra and ventral tegmental area after treatment with paroxetine, and the labeling was reduced drastically in the zona incerta and mediobasal hypothalamus. The immunoreactive axons in the target regions (striatum, cortex, hippocampus, and median eminence) almost disappeared only in the paroxetine-treated rats. Conversely, after treatment with agomelatine, a moderate reduction in immunoreactivity in the substantia nigra was found without appreciable modifications in the ventral tegmental area, zona incerta, and mediobasal hypothalamus. Nevertheless, no sexual or copulatory behavior was observed in any of the experimental or control groups. Conclusion: Paroxetine but not agomelatine was associated with important decreased activity in dopaminergic areas such as the substantia nigra and ventral tegmental areas that could be associated with sexual performance impairment in humans after antidepressant treatment.

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