Advanced search
Start date
Betweenand


Effects of the neurotoxin MPTP on the myocardial structure in C57/BL mice

Full text
Author(s):
Tais Harumi de Castro Sasahara
Total Authors: 1
Document type: Doctoral Thesis
Press: São Paulo.
Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
Defense date:
Examining board members:
Antonio Augusto Coppi Maciel Ribeiro; Francisco Javier Hernandez Blazquez; Eliane Florencio Gama; Márcia Rita Fernandes Machado; Romeu Rodrigues de Souza
Advisor: Antonio Augusto Coppi Maciel Ribeiro
Abstract

Parkinson´s disease (PD) is a neurodegenerative disorder mostly characterised by a profound reduction of dopamine in the striatum due to a dramatic loss of dopaminergic neurons in the substantia nigra (pars compacta). The disease is not only characterised by a motor disorder but also present cardiovascular dysautonomia. The disease has been chemically induced in rats and mice using neurotoxins such as 1-metyl-1-4-phenyl-1,2,3,6-tetrahydropyrimidina (MPTP), 6-OHDA and rotenone. In the nineties, transgenic α-synuclein mice have recently been used as a model of PD and alpha-synuclein aggregation, because the overexpression of this protein is related to the development of parkinsonism associated to the sympathetic cardiac denervation. Although, the cardiac denervation in PD and its consequences in myocardium is not well defined because the literature reports no reliable quantitative methods. Therefore, the myocardium of the C57/BL mice was investigated in the neurotoxin animal model (MPTP) applying tridimensional morphoquantitative methods (stereological). In this study, we observed an increase of 0,8%, 5,3% and 2,4% in ventricular wall volume, in cardiac interstitial volume and in cardiac interstitial volume density, respectively, in the MPTP group. The lumen ventricular volume, the ventricular volume, the cardiac muscle fibre and their volume density were, respectively, 11,7%, 0,9% , 2,3% and 1,7% larger in control group. The total number of cardiomyocyte nuclei was 14,8% lower in MPTP group as well as the total number of cardiomyocyte that was 19% lower for this group too. Significant difference was observed between the groups to the total number of cardiomyocyte. No significant difference, however, was detected for the others estimated parameters. (AU)