Neurochemistry and Neuropharmacology
Author: María Elena ARCE | Email: earce.arce7@gmail.com
Maria Elena Arce1°2°, Helga Myrna Blanco1°2°, Maria Belen Torres Basso1°2°, Gladys Maria Ciuffo1°2°
1° Facultad de Quimica, Bioquimica y farmacia . UNIVERSIDAD NACIONAL DE SAN LUIS
2° IMIBIO-SL . CONICET. SAN LUIS
The renin angiotensin system (RAS) is an endocrine system considered relevant in physiologic and pathophysiologic mechanisms, including neurodegenerative diseases. Widespread distribution of angiotensin receptors (Angiotensin type-1 receptor [AT1R] and type-2 [AT2R] has been found in the central nervous system including Substantia nigra (SN). AT1R and AT2R expressions are regulated differently, and regulation is also tissue-specific. Previously, we evaluated the effect of 10-week treatment of Wistar rats with rotenone in an experimental model of Parkinson`s disease. Significant changes were observed on behavioral motor tests after 5 weeks of treatment and altered distribution of angiotensin II receptors were found in SN of treated animals. Taking into account these observations, the aim of this work was to study more accurately the time when these alterations appears in SN and its correlation with the motor impairments in this model. Histological and immunohistochemical analyses were performed in rotenone-treated rats after 3-week, 5-week and 9-week of treatment. The number of tyrosine hydroxylase immunoreactive dopamine neurons decreased in the SN of the 9- week rotenone-treated rats. Indeed, the number of AT1R and AT2R immunopositive cells in SN was lower in the 5 and 9 –week rotenone- treated rats than the 3-week treated animals.
The physiological and pathological roles of RAS require more studies to elucidate their functions.