Ultrastructural alterations of choroid plexuses of lateral ventricles of rats (Rattus norvegicus) submitted to experimental chronic alcoholism

Abstract

-Adult male rats (Wistar lineage) were alcoholized with sugar cane liquor diluted at 30 0 GL during 300 days and sacrificed every 60 days in 5 stages. Samples of choroid plexuses of lateral ventricles were collected and examined at transmission electronic microscope to detect possible ultrastructural alterations and to raise possible pathological correlations. Gradual changes were observed in these animals during all the experiment: dilatation and enlargement of cisternae of Golgi complex, dilatation of RER, presence of digestive vacuoles and a large amount of pinocytic vesicles as well as vesicles with electronlucent content throughout cytoplasm, as well as an enlargement of intercellular space between basolateral interdigitation of the cells and of the connective tissue. The changes observed in the epithelium and connective tissue of choroid plexuses specially in 240 and 300 days of treatment are presumably due to a disturbance in hydroelectrolitic homeostasis, contributing to several morpho-functional disturbs of central nervous system. No changes were observed in the control group animals.KEY WORDS: chronic alcoholization, choroid plexus, rats, morphologic alterations. Alterações ultraestruturais dos plexos coróides dos ventrículos laterais de ratos (rattus norvegicus) submetidos a alcoolismo crônico experimentalRESUMO -Ratos machos adultos (linhagem Wistar) foram alcoolizados com aguardente de cana diluída a 30 0 GL durante 300 dias e sacrificados a cada 60 dias em 5 etapas. Amostras dos plexos coróides dos ventrículos laterais foram coletadas e examinadas ao microscópio eletrônico de transmissão para detectar possíveis alterações ultraestruturais e suas correlações patológicas. Alterações graduais foram observadas nestes animais durante todo o experimento: dilatação e aumento das cisternas de complexo de Golgi, dilatação do retículo endoplasmático rugoso, presença de vacúolos digestivos e grande quantidade de vesículas pinocíticas assim como de vesículas de conteúdo elétron-lúcido por todo o citoplasma, além de aumento do espaço intercelular, entre as interdigitações das células assim como no tecido conjuntivo. As alterações observadas no epitélio e no tecido conjuntivo dos plexos coróides, especialmente aos 240 e 300 dias de tratamento, são devidas possivelmente a distúrbios na homeostase hidro-eletrolítica, podendo assim contribuir para vários distúrbios morfo-funcionais do sistema nervoso central. Nenhuma alteração foi observada nos animais do grupo controle. PALAVRAS-CHAVE: alcoolização crônica, plexo coróide, ratos, alterações morfológicas.Studies conducted in experimental animals as well as in man showed that excessive consumption of alcohol involves mainly the central nervous system(CNS) 1 . So, Clair 1 observed that 40% to 70% of chronic alcoholics show an enlargement of encephalic ventricles and cortical reduction 1 . According to Fortes 2 , the difusion of ethanol through the hemato-encephalic barrier occurs

Glutamate Export at the Choroid Plexus in Health, Thiamin Deficiency, and Ethanol Intoxication: Review and Hypothesis

“…Second, ethanol permeates and disrupts lipid membranes, including those of the mitochondria. Whether a single ethanol dose causes detectable structural change is yet to be investigated but chronic ethanol exposure causes ultrastructural changes to the CPE of both adult rats and fetal mice (Craciun et al., 1989; Tirapelli et al., 2000). The changes include some features unique to this epithelium and some common to the changes seen in whole brain (Karwacka, 1980; Karwacka et al., 1980) and liver (Iseri et al., 1966).…”

“…( D ): Apical portion of CPE cell; mi, microvilli; ve, vesicles; vh, heterogeneous material (16,000×). Reproduced from Arq Neuropsiquiatr with permission (Tirapelli et al., 2000).…”

“…Acute, temporary dysfunction of the CPE might not necessarily be accompanied by ultrastructural changes. However, chronic ethanol exposure has been shown to damage the ultrastructure of the CPE (Craciun et al., 1989; Tirapelli et al., 2000), hence it is possible that some such changes might result from a large single ethanol dose or from a glucose load in thiamin deficiency. Ultrastructural studies under these conditions should be timed in relation to the acute perturbation, to define the period to demonstrated change and to its recovery.…”

“…( C ) Junctional complex: az, adhesion zonule; d, desmosome; oz, occlusion zonule (50,000×). Reproduced from Arq Neuropsiquiatr with permission (Tirapelli et al., 2000).…”

Ação da matriz óssea bovina desmineralizada na neoformação óssea em ratos submetidos ao alcoolismo experimental: avaliação histológica e histométrica

“…A dieta alcoólica utilizada no presente trabalho (25%) está de acordo com trabalhos anteriores, onde os grupos experimentais foram submetidos a uma adaptação gradativa, tornando esses animais alcoólatras crônicos (WILLIS et al, 1983;TIRAPELLI et al, 2000).…”