Contrasting effects of repeated treatment vs. withdrawal of methamphetamine on tyrosine hydroxylase messenger RNA levels in the ventral tegmental area and substantia nigra zona compacta of the rat brain

We examined cell type-specific expression and distribution of rat brain angiotensin converting enzyme 2 (ACE2), the receptor for SARS-CoV-2, in rodent brain. ACE2 is ubiquitously present in brain vasculature, with the highest density of ACE2 expressing capillaries found in the olfactory bulb, the hypothalamic paraventricular, supraoptic and mammillary nuclei, the midbrain substantia nigra and ventral tegmental area, and the hindbrain pontine nucleus, pre-Botzinger complex, and nucleus of tractus solitarius. ACE2 was expressed in astrocytes and astrocytic foot processes, pericytes and endothelial cells, key components of the blood-brain-barrier. We found discrete neuronal groups immunopositive for ACE2 in brainstem respiratory rhythm generating centers including the pontine nucleus, the parafascicular/retrotrapezoid nucleus, the parabrachial nucleus, the Botzinger and pre-Botzinger complex and the nucleus of tractus solitarius; in arousal-related pontine reticular nucleus and in gigantocellular reticular nuclei; in brainstem aminergic nuclei, including substantia nigra, ventral tegmental area, dorsal raphe, and locus coeruleus; in the epithalamic habenula, hypothalamic paraventricular and suprammamillary nuclei; and in the hippocampus. Identification of ACE2-expressing neurons in rat brain within well-established functional circuits facilitates prediction of possible neurological manifestations of brain ACE2 dysregulation during and after COVID-19 infection.

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Dietary calcium deficiency causes a reduction in calretinin mRNA in the substantia nigra compacta-ventral tegmental area of rat brain

Molecular Brain Research ◽

10.1016/0169-328x(94)90289-5 ◽

1994 ◽

Vol 25 (1-2) ◽

pp. 140-142 ◽

Cited By ~ 5

Author(s):

Kenneth I. Strauss ◽

David M. Jacobowitz ◽

Jay Schulkin

Keyword(s):

Substantia Nigra ◽

Rat Brain ◽

Ventral Tegmental Area ◽

Dietary Calcium ◽

Calcium Deficiency ◽

Ventral Tegmental ◽

Dietary Calcium Deficiency

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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

Journal of Clinical Medicine ◽

10.3390/jcm8020133 ◽

2019 ◽

Vol 8 (2) ◽

pp. 133 ◽

Cited By ~ 4

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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