An immunocytochemical study of the magnocellular neurosecretory nuclei was performed in the snake Natrix maura and the turtle Mauremys caspica by use of antisera against: (1) a mixture of both bovine ...neurophysins, (2) bovine oxytocin-neurophysin, (3) arginine vasotocin, and (4) mesotocin. Arginine vasotocin- and mesotocin-immunoreactivities were localized in individual neurons of the supraoptic and paraventricular nuclei, with a distinct pattern of distribution in both species. The same cells appeared to be stained by the anti-oxytocin-neurophysin and antimesotocin sera. The supraoptic nucleus can be subdivided into rostral medial and caudal portions. In N. maura, but not in M. caspica, neurophysin-immunoreactive neurons were found in the retrochiasmatic nucleus. No immunoreactive elements were seen in the suprachiasmatic nucleus of both species after the use of any of the antisera. A dorsolateral aggregation of neurophysin-containing cells, localized over the lateral forebrain bundle, was present in both species. Magnocellular and parvocellular neurophysin-immunoreactive neurons were present in the paraventricular nucleus of both species. In the turtle, the paraventricular neurons were arranged into four distinct layers parallel to the ependyma; these neurons were bipolar with the major axis perpendicular to the ventricle, and many of them projected processes toward the cerebrospinal-fluid compartment. In N. maura a group of large neurons of the paraventricular nucleus was found in a very lateral position. The posterior lobe of the hypophysis and the external zone of the median eminence contained arginine vasotocin- and mesotocin-immunoreactive nerve fibers. The lamina termialis of both species was supplied with a dense bundle of fibers containing immunoreactive neurophysin. Neurophysin-immunoreactive fibers were also present in the septum, some telencephalic regions, including the cortex and the olfactory tubercule, in the paraventricular organ, and the periventricular and periaqueductal gray of the brainstem.
During brain development, Pax6 is expressed in specific regions of the diencephalon including secretory cells of the subcommissural organ (SCO), a circumventricular organ at the forebrain-midbrain ...boundary that originates from the pretectal dorsal midline neuroepithelial cells beneath the posterior commissure (PC). Homozygous small eye (Sey/Sey) mice lack functional Pax6 protein and fail to develop the SCO, a normal PC and the pineal gland. Small eye heterozygotes (Sey/+) show defective development of the SCO's basal processes which normally penetrate the PC, indicating that normal development of the gland requires normal Pax6 gene-dosage. A correlation between the defects of SCO formation and altered R- and OB-cadherin expression patterns in the SCO is observed in mutants suggesting a role for cadherins in SCO development.
The subcommissural organ (SCO) of the snake Natrix maura was studied by use of the immunoperoxidase procedure. Primary antisera against bovine neurophysins (Nps I + II, OXY-Np), oxytocin (OXY), ...mesotocin (MST), arginine-vasotocin (AVT), somatostatin (SOM), beta-endorphin (END) and bovine Reissner's fiber were used. A conventional ultrastructural study, with special emphasis on the nerve fibers present in the SCO, was also performed. Nerve fibers containing immunoreactive OXY-Np and MST were seen to reach the SCO. The staining of adjacent sections with the anti-Reissner's fiber serum showed that the OXY-Np- and MST-immunoreactive fibers were distributed among the cell bodies and processes of the ependymal secretory cells. No fibers containing immunoreactive OXY, AVT, SOM or END were found in the SCO. The ultrastructural analysis revealed in the SCO the presence of nerve fibers filled with electron-dense granules, 170-210 nm in diameter. Although a direct apposition between these fibers and the SCO cells was frequently seen, no synaptic differentiations were identified. Structures identical to the Herring bodies (found in the neurohypophysis) were seen in the SCO.
Paraphyseal epithelial cells of Natrix maura have been studied with light and electron microscopy. They showed a clear polarity apically related to the third ventricle and, basally, to a connective ...tissue layer which surrounded the whole organ. The apical surface of the cells, attached by junctional complexes, showed many microvilli, scarce cilia, and some pinocytotic coated vesicles. In their apical cytoplasm many mitochondria and a well-developed golgi apparatus and endoplasmic reticulum were observed. Whereas lamellar bodies were abundant and closely related with mitochondria, glycogen particles were absent. Basal cell membrane showed infoldings where pinocytotic coated vesicles were detected. In the connective tissue layer, fenestrated sinusoids and fibrocytes, as well as rare unmyelinated nerve fibers engulfed by Schwann cells, were present. The possible active role of paraphyseal cells in exchanging substances between cerebrospinal fluid and blood is discussed.
Seasonal variations in the secretory activity of the subcommissural organ (SCO) of snakes and turtles was studied by immunocytochemistry, lectins, and electron microscopy. In animals sacrificed in ...summer, immunoreactive material, mostly devoid of sialic acid, occupied the whole cytoplasm. Cells showed many distended cisternae of rough endoplasmic reticulum and secretory granules. In animals sacrificed in winter, patches of immunoreactive sialic acid-rich material occupied the apical cytoplasm. Cells lacked distended cisternae and the secretory granules formed clusters. These results suggest a decreased synthesis and release of secretory material in the SCO of lethargic reptiles.
Vitamix® is a dietary product composed of a hydro-alcoholic extract of cereals and pulses with honey, calcium glycerophosphate, vitamins B and D, selenium and fluoride. The basic product, Ceregumil®, ...patented in 1912, was highly popular as tonic and consumers reported a feeling of health, resistance to illness, and increased predisposition to work and exercise.
In the present study we analysed the effect of Vitamix® used as dietary supplement, on several physiological parameters in laboratory rats. We periodically performed hemograms and measured intake and weight, as well as blood levels of glucose, triglycerides, cholesterol, transaminases and malondialdehyde, a lipoperoxidation product. Physical probes were performed and a histochemical study was done in the liver.
Rats fed with Vitamix® displayed lower intake and body weight in adult ages, showed and increased antioxidant activity, higher resistance in the wire hang test and lower fatigue in the Morris pool, specially those specimens considered as bad performers supplemented with Vitamix®. The rest of the measured parameters remained similar to control and no hepatic alterations were found.
This study supports a scientific basis to know the effect of these complements over physiological parameters.
Objetivo Vitamix® es un producto dietético compuesto por un extracto hidroalcohólico de cereales y leguminosas con miel, glicerofosfato de calcio, vitaminas B y D selenio y flúor. El producto base, ...Ceregumil®, patentado en 1912, ha sido muy popular como reconstituyente, y los usuarios refieren una sensación de salud, resistencia a enfermedades o mayor predisposición para el trabajo o el ejercicio. Material y método En el presente trabajo se analiza el efecto de Vitamix®, utilizado como suplemento alimenticio en ratas de laboratorio, en diversos parámetros fisiológicos y pruebas físicas. Periódicamente se realizaron hemogramas y se midieron la ingesta y el peso de los animales, así como las concentraciones sanguíneas de glucosa, triglicéridos, colesterol, transaminasas y malondialdehído, un producto de la lipoperoxidación. Se realizaron pruebas de resistencia física y se llevó a cabo un estudio histoquímico del hígado. Resultados Los animales que tomaron Vitamix® tenían menor peso e ingesta en edades avanzadas, mostraban mayor capacidad antioxidante, mayor resistencia en la prueba del alambre y menor fatiga en la piscina de Morris. En este último caso, la mejoría era notable en los animales considerados de mal desempeño suplementados con Vitamix®. El resto de los parámetros medidos se mantuvieron estadísticamente similares a los de los controles y no se observaron alteraciones hepáticas de ningún tipo. Conclusiones Este estudio supone una base científica y experimental para conocer el efecto de dichos complementos en los parámetros fisiológicos.
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