Serotonergic dysfunction in a model of parkinsonism induced by reserpine

Pollyana C Leal; José Marcos M Bispo; Rovena C G J Engelberth; Kayo Diogenes de A Silva; Ywlliane R Meurer; Alessandra M Ribeiro; Regina H Silva; Murilo Marchioro; José R Santos

doi:10.1016/j.jchemneu.2018.12.011

Serotonergic dysfunction in a model of parkinsonism induced by reserpine

J Chem Neuroanat. 2019 Mar:96:73-78. doi: 10.1016/j.jchemneu.2018.12.011. Epub 2018 Dec 28.

Authors

Pollyana C Leal¹, José Marcos M Bispo², Rovena C G J Engelberth³, Kayo Diogenes de A Silva³, Ywlliane R Meurer⁴, Alessandra M Ribeiro⁵, Regina H Silva⁶, Murilo Marchioro², José R Santos⁷

Affiliations

¹ Behavioral and Evolutionary Neurobiology Laboratory, Department of Physiology, Federal University of Sergipe, São Cristovão, 49100-000, SE, Brazil; Post-Graduate Program of Dentistry, Federal University of Sergipe, Aracaju, 49060-100, SE, Brazil.
² Behavioral and Evolutionary Neurobiology Laboratory, Department of Physiology, Federal University of Sergipe, São Cristovão, 49100-000, SE, Brazil.
³ Laboratory of Neurochemical Studies, Department of Physiology, Federal University of Rio Grande do Norte, Natal, 59072-970, RN, Brazil.
⁴ Laboratory of Neurochemical Studies, Department of Physiology, Federal University of Rio Grande do Norte, Natal, 59072-970, RN, Brazil; Post-Graduate Program of Biological Sciences, Federal University of Rio Grande do Norte, Natal, 59072-970, RN, Brazil.
⁵ Laboratory of Neuroscience and Bioprospecting of Natural Products, Department of Bioscience, Universidade Federal de São Paulo, Santos, 11015-020, SP, Brazil.
⁶ Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, 04023-062, SP, Brazil.
⁷ Behavioral and Evolutionary Neurobiology Laboratory, Department of Bioscience, Federal University of Sergipe, Itabaiana, 49500-000, SE, Brazil. Electronic address: joseronaldosantos@gmail.com.

PMID: 30597197
DOI: 10.1016/j.jchemneu.2018.12.011

Abstract

Parkinson's disease (PD) is mainly characterized by a dopamine deficiency accompanied by structural and functional changes in striatal neuronal projections. However, studies have considered PD as a multi-systemic disease in which the neurodegenerative process extends beyond the dopaminergic system. Therefore, the purpose of the present study was to investigate the time-course of serotonergic neuron damage in a progressive model of parkinsonism induced by a low dose of reserpine. Thus, male Wistar rats received 4 (ST, short-treatment of reserpine) or 10 (MT, middle-term treatment of reserpine) subcutaneous injections of vehicle or reserpine (0.1 mg/kg) at a volume of 1 mL/kg body weight, on alternate days. Animals were euthanized 48 h after the last injection for immunohistochemical analysis. After ST, 5-HT immunoreactivity decreased in hippocampal subareas (CA1 and CA3) and medial prefrontal cortex (mPFC) compared to vehicle. Furthermore, animals MT-treated also showed progressive decrease of 5-HT immunoreactivity in CA1 and CA3 subareas. Conversely, a significant increase of 5-HT immunoreactivity was found in mPFC and dorsal raphe nucleus (DRN) in animals submitted to MT when compared to ST exposure. The results showed that, in the repeated low-dose reserpine rat model, variations in the immunoreactivity of 5-HT start early in the course of progressive parkinsonism.

Keywords: 5-HT; Animal model; Parkinson’s disease; Serotonin.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adrenergic Uptake Inhibitors / toxicity*
Animals
Brain / drug effects
Brain / metabolism*
Male
Parkinsonian Disorders / metabolism*
Rats
Rats, Wistar
Reserpine / toxicity*
Serotonin / metabolism*

Substances

Adrenergic Uptake Inhibitors
Serotonin
Reserpine