Histological study on the possible protective action of ginseng on the injurious effect induced by acrylamide on the midbrain in adult male albino rat

Acrylamide is a synthetic chemical compound commonly used in many branches of industry. Researchers have found acrylamide in certain foods that were heated to a temperature above 120[degree]C. Ginseng is a widely used herbal medicine with numerous beneficial effects. Ginseng is suggested to contribute to a protective effect in neurodegenerative disorders. The aim of the present study was to evaluate the possible protective effect of ginseng against the midbrain injury induced by acrylamide in adult male albino rats. A total of 35 adult male albino rats were used. They were divided into three groups. Group I [15 animals] was allowed water ad libitum and fed a standard diet [control]. Group II [10 animals] was given acrylamide orally by means of a gastric tube daily at a dose of 30 mg/kg for 4 weeks. Group III [10 animals] was given acrylamide daily at the same dissolution, dose, route and duration as group II concomitantly with ginseng solution through a gastric tube at a dose of 20 mg/kg. Samples from the brainstem were taken and processed for light and electron microscopic investigation. Light microscopic examination of the midbrain of the acrylamide-treated animals showed signs of injury. Glial fibrillary acidic protein-positive cells were more abundant in the midbrain of treated animals compared with control animals. Ultrastructural study of the midbrain of the acrylamide-treated group showed dilated RER in association with mitochondria with destroyed cristae. Many myelinated nerve fibers showed degenerative changes. These structural changes were much less pronounced in animals concomitantly treated with acrylamide and ginseng. Ginseng can reduce the severity of the injurious effects induced by acrylamide

Distribution of NADPH-diaphorase in rat mesencephalon: a light and electron microscopical study

NADPH-diaphorase is a useful technique to reveal NO producing neurons at light microscopic level (LM). A modification of the technique using the tetrazolium salt BSPT as substrate, is useful to study the ultrastructure of NO neurons. The aim of this work was to perform a detailed analysis of NADPH-diaphorase reactive neurons in rat mesencephalon both at light and electron microscopic levels. NADPH-diaphorase reactive neurons were observed in superior colliculus, in central gray matter, in dorsal and medial raphe and in the pedunculopontine tegmental nucleus using two histochemical techniques at LM. Electron microscopy showed deposits on membranes of the endoplasmic reticulum, Golgi apparatus and nuclear envelope of dorsal raphe neurons. Presynaptic and postsynaptic terminals showed deposits on membranous elements but postsynaptic terminals also showed deposits on the inner surface of their membranes. Further physiological studies are needed to clarify the meaning of the ultrastructural findings such as the putative interaction of NOS with postsynaptic proteins, receptors or membranous channels.

Estudio citofotométrico e citoquímico dos neuronios do nucleo istmo de gallus gallus domesticus (L) / Cytophotometric and cytochemical study of the nucleo istmo neurons of the gallus gallus domesticus

O estudo citofotométrico e citoquímico dos neurônios do núcleo istmo de Gallus gallus domesticus (L) com um dia e quatro meses de desenvolvimento pós-natal foi realizado com dois processos: violeta cresilo e ferro coloidal e um citofotomicroscópio Zeiss-modelo SMPH-01 unido a computador digital PDP-12. A pesquisa mostrou as diferenças existentes entre os neurônios das duas zonas do núcleo istmo: pars magnocelular e pars parvicelular. Nos pintos como um dia, os neurônios da pars magnocelular säo escassos e com áreas citoplasmáticas e nucleares grandes. O núcleo é bem delimitado, claro e com posiçäo excêntrica. Os neurônios la pars parvicelular säo pequenos e numerosos, com núcleos redondos e nucleólos visíveis. A forma da célula é ovóide e apresenta o citoplasma corado intensamente com violeta cresilo. A distribuiçäo dos valores de densidade óptica no citoplasma dos neurônios muda na pars magnocelular e na pars parvicelular. As células do núcleo istmo säo mais escuras, apresentando valores de densidade óptica mnuito alto, nos pintos com quatro meses. A reaçäo com ferro coloidal é mais forte nos exemplares com quatro meses. Sobre os resultados foram aplicados método estatísticos que permitem determinar as diferenças significativas