Name: ELISA FRAGA GOMES
Publication date: 12/07/2017
Advisor:
Name |
Role |
|---|---|
| ESTER MIYUKI NAKAMURA PALACIOS | Advisor * |
| LÍVIA CARLA DE MELO RODRIGUES | Co-advisor * |
Examining board:
| Name |
Role |
|---|---|
| CRISTINA MARTINS E SILVA | External Examiner * |
| ESTER MIYUKI NAKAMURA PALACIOS | Advisor * |
| SUELY GOMES DE FIGUEIREDO | Internal Examiner * |
Summary: During the inhalation of crack, the burning of cocaine content generates a product named anhydroecgonine methyl ester (AEME). This compound is exclusively produced in the process of cocaine pyrolysis, which has been used as an analytical marker for crack use.There are few data in the literature on the effects of the substance on the central nervous system, as well as the effects on cognitive function and its neurotoxicicity. The aim of this study was to investigate the effects of AEME on spatial working memory and on parameters of oxidative stress in specific brain structures such as prefrontal cortex (PFC), hippocampus (HPC) and striatum (STR). Rats well-trained in an 8-arm radial maze (8-RM) and with a cannula implanted into the third ventricle (AP: -0.3 mm; L: 1 mm; B: 3.6 mm) underwent to acute intracerebroventricular (icv) administration of AEME at doses of 10, 32 or 100 μg and were tested 5 minutes later in 1-hour delayed tasks in the 8-RM. An independent group of animals received acute icv administration of AEME at doses of 10 (n = 5), 32 (n = 5) or 100 μg (n = 5) or saline (n = 5) for analysis of oxidative stress parameters such as advanced oxidation protein products (AOPP); lipid peroxidation through the analysis of reactive species the thiobarbituric acid (TBA-RS); activity of antioxidant enzymes, catalase (CAT); glutathione peroxidase (GPx) and superoxide dismutase (SOD), in the PFC, HPC and STR. Animals showed significantly higher number of errors in the post-delay performance of 1-hour delayed task when they received AEME icv at doses of 32 g (P < 0.05) and 100 g (P < 0.05) when compared to the control treatment (saline). Animals receiving AEME icv at the dose of 100 g showed increased (P < 0.05) AOPP levels when compared to animals receving the dose of 10 g in the STR, and also showed increased (P < 0.05) activity of GPx enzime in the STR when compared to the control group, and to groups receiving the doses of 32 g (P < 0.05) and 10 g (P < 0.01). As a conclusion results of this study showed that the AEME impairs long-termed spatial working memory in a dose-dependent manner and induced increased protein oxidation and changed the levels of one of antioxidant enzymes, the GPx, in the striatum.
