ABSTRACT
Nicotine is the most important alkaloid compound in tobacco. One of the major effects of nicotine is stimulation of mesocorticolimbic system. Prefrontal cortex plays a pivotal role in personality and mental state. It is considered the main cause of addiction as it is located in mesocorticolimbic dopamine system. Twenty four male rats were divided into four groups based on nicotine administration dose (0, 0.5, 1 and 1.5 g/kg). After animals were anesthetized, their brains were fixed using transcardiac method. Tissue processing and Golgi staining were performed and the stained tissue sections were analyzed by optic microscope and Motic software. By increasing the dose, nicotine significantly decreased the number of neuronal processes. In the higher dose, nicotine caused a significant decrease and increase in the size of pericarions and dendritic spines, respectively (p<0.05). Nicotine administration can decrease the size of pericarion and number of dendritic spines in the prefrontal cortex.
La nicotina es el compuesto alcaloide más importante del tabaco. Uno de sus principales efectos es la estimulación del sistema mesocorticolímbico. La corteza prefrontal desempeña un papel fundamental en la personalidad y estado mental. Esta es considerada la principal causa de la adicción, ya que se encuentra en el sistema mesocorticolímbico dopaminérgico. Veinticuatro ratas macho fueron divididas en cuatro grupos basados en la dosis de administración de nicotina (0, 0,5, 1 y 1,5 g/kg). Luego fueron anestesiados y sus cerebros se fijaron mediante perfusión transcardíaca. Se realizó el procesamiento de tejidos y las secciones bajo tinción de Golgi fueron analizadas mediante microscopia óptica y el software Motic. Con el aumento de dosis, la nicotina redujo significativamente el número de procesos neuronales. En la dosis más alta, la nicotina causó una disminución y aumento significativo en el tamaño de pericarion y espinas dendríticas, respectivamente (p<0,05). La administración de nicotina puede disminuir el tamaño del pericarion y el número de espinas dendríticas en la corteza prefrontal.
Subject(s)
Animals , Male , Rats , Prefrontal Cortex/drug effects , Nicotine/pharmacology , Rats, Wistar , Prefrontal Cortex/ultrastructure , Dendritic Spines/drug effects , Dendritic Spines/ultrastructure , Microscopy , Neurons/drug effects , Neurons/ultrastructure , Nicotine/administration & dosageABSTRACT
Iron deficiency anemia is the most common nutrient deficiency disease. In early life it is associated with affection of the behavioral and motor development. Was to investigate the effect of low iron diet on the frontal cortex of young rats and to assess the possibility of recovery after using high iron diet. Forty two male albino rats [4 weeks age] were divided into 2 groups, group I considered as control group that was further subdivided into 3 subgroups, group II, was divided into 3 subgroups. Subgroup IIa, comprised animals that received low iron diet [4mg Fe/ kg diet] for 4 weeks. Subgroup IIb, received the low iron diet for 4 weeks then they were allowed high iron diet [70mg Fe/kg diet] for other 4 weeks. Subgroup IIc, received the low iron diet for 4 weeks, and then allowed the high iron diet for 8 weeks. The pyramidal cells of animals that received low iron diet showed nuclear and cytoplasmic changes. There was a highly significant increase in the number of pyramidal cells showing depletion of Nissl granules [chromatolysis]. Some of the synaptic sites showed distorted synaptic vesicles and absent mitochondria. The oligodendrocytes showed shrunken condensed nuclei and appeared to be surrounded by unmyelinated nerve fibers. The mean values of haemoglobin concentration in blood and serum ferritin were decreased. The pyramidal cells and oligodendrocytes of animals that received the high iron diet for 4 weeks after the low iron diet did not show a significant improvement. Intake of high iron diet for 8 weeks after the low iron diet resulted in marked improvement in the microscopical appearance of the frontal cortex of young rats and in the levels of blood haemoglobin and serum ferritin. Low iron diet in young age resulted in marked affection of the frontal cortex. Treatment by high iron diet is advised to be used for a long period to obtain a significant improvement