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A Toledano

Publications and source records attributed to A Toledano.

At least 91 records · Page 5Linked to original sources
PubMed1978

Glycoproteins and polyanions in the synapses of rat and mouse central nervous system.

In the present work, it is investigated the location and characteristics of receptors for Con A in synapses of rat and mouse central nervous system. Negatives charges of synaptic surface are also studied. It is observed the presence of glycoproteins on synaptosomal plasma membrane. Presence of negatives charges homogenously distributed all over the synaptosome surface is also notice. These negative charges are revealed by Colloidal Iron, FeOH++cation and cationized Ferritin. Enzymatic extraction experiments suggest that presence of sulphated mucopolysaccharides.

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PubMed1978

Diaminobenzidine oxidation in cerebellar histological sections.

Cerebellar histological sections were incubated in media containing 3,3'-diaminobenzidine (DAB). Microscopic observation showed the presence of oxidated DAB in all cerebellar cells. Said oxidation of DAB in the cerebellar structures was produced in the absence, as well as in the presence, of exogenous H2O2 in the incubation medium. The erythrocytes existent in the blood vessels were capable of oxidating more intensely the DAB when H2O2 was present in the incubation medium. When the sections were pretreated and incubated with CNK, sodium azide and perodic acid, the oxidation of DAB was not produced. The observation with electron microscope showed that the DAB oxidation is produced in mitochondria, coated vesicles, and lysosomes. The possible mechanisms intervening in the oxidation of DAB in cerebellar structures are discussed.

3,3'-Diaminobenzidine↗
PubMed1978

Evidences for the existence of glycoproteins and mucopolysaccharides metabolic cycles in the cerebellum of birds and mammals.

Cerebellum glycoproteins of rats and ducks are studied using sugar-specific agglutinins. It is used the Con A-Peroxidase-DAB technique described by Bernhard and Avrameas (1971). Other agglutinins (Tetragonolobus Purpureus Lectin, Wheat Germ Agglutinin and Soybean Agglutinin) fixed to Peroxidase according to the technique of Gonatas and Avrameas (1973) are also used. The techniques for mucopolysaccharides as described Martínez-Rodriguez et al., (1976) are carried out as well. By means of all these techniques, results that suggest the existence of metabolic cycles in Purkinje cells are obtained.

Animals↗
PubMed1977

Mucopolysaccharides in the dog spinal cord and dorsal root ganglia. A histochemical study.

A histochemical study of mucopolysaccharides in the dog spinal cord and dorsal root ganglia is reported in this paper. The histochemical techniques used were the following: PAS, colloidal iron, toluidine blue (pH 5.4 and 3.5), thionine (pH 5.4 and 3.5) and alcian blue 8GX (pH 1 and 2.5). Some histological stains were used also. Two types of neurons could be observed in spinal cord sections stained with colloidal iron techniques. In some neuron a border line of mucosubstances could be seen. In the dorsal root ganglia, different patterns of Nissl bodies distribution in neurons were described. This different distribution of Nissl bodies is associated with different metachromatic colorations of neurons. By using the colloidal iron method, two types of neurons were also revealed in the dorsal root ganglia: some neurons are of a yellow, small-sized and star-shaped type and others are of a light green, larger and round-shaped type. Mucosubstances in the endoneurium and perineurium of nerve fibers, in the Ranvier nodules and in the Schmidt-Lantermann incisures were observed. The possibility that the functional rhythm in some cases might be responsible for the difference in coloration between the dorsal root ganglia neurons is suggested.

Animals↗
PubMed1977

[Histochemical study of glutamate dehydrogenase activity in the medulla, bulb and in the central cerebellar nuclei of various vertebrates].

In this work we research into the GDH location of the spinal cord, in the medullar oblongata and in the central cerebellar nuclei of the rat, cat, dog, chicken, lizard (Lacerta lepida), and Toad (Bufo calamita). The GDH is located at the cytoplasm and at the neuronal prolongations, at oligodendrocytes cells, at Lecerta ependimary glial cells, and at the capillary walls.

Animals↗
PubMed1976

A histochemical investigation on mucopolysaccharides in the dog sympathetic ganglia.

A histochemical study in the dog Superior Cervical ganglion and in the Cervicothoracic or Stellate ganglion is reported. The mucopolysaccharide composition of these ganglia are studied by means of five histochemical techniques. The different histochemical composition between the neurons of these ganglia is investigated. In the sections stained with the PAS technique some neurons appeared more intensely stained than the others. With Thionin or Toluidine blue some neurones appeared more metachromatic than others. A peculiar distribution of the Nissl bodies, related with metachromasia, is reported. In sections stained with the Colloidal Iron method yellow neurons like those presented in the dorsal root ganglia were not found in the sympathetic ganglia. This fact suggests that the yellow neurons might be a different type of neuron. The possibility that the staining variations associated to the distribution of the Nissl bodies perhaps correspond to different functional states of the same type of neurons is also suggested.

Animals↗
PubMed1976

Histochemical study of mucopolysaccharides in the subthalamic region of rats.

Histological sections of the Subthalamic region of rats were treated with solutions of: Toluidin Blue, Thionin, Alcian Blue and Colloidal Iron. The microscopic observation of the histological sections treated with those histochemic reactions showed the existence in the Subthalamic region of three neuronal types, differentiated between them because of the morphologic and histochemic points of view. In the LUY's Subthalamic nucleus was observed only one neuronal type, while in the nucleus of the FOREL's field and in the Zona incerta were found two very special types of neurons (alpha and beta) differentiated between them because of their reaction before the Collidal Iron. It is suggested the possibility that those different types of neurons have different functional characteristics.

Alcian Blue↗
PubMed1976

Aspartate aminotransferase activity and glutamic dehydrogenase in the cerebellar cortex in several species of animals. A histochemical study.

The histochemical study of the consumption of glutamic acid by way of the aspartate aminotransferase and the glutamic dehydrogenase in the cerebellar cortex of several species of animals have demonstrated that in that nerve centre exists some structures in which the mentioned consumption is specially or exclusively realized by means of one way and not for other different one. Is observed, as well, that in the rats, chicken and lizard, the baskets that surround the Purkinje cells are constituted by basket cells axons and by recurrent collaterals of Purkinje axons and that those structures have an intense aspartate aminotransferase activity, but not glutamic dehydrogenase. The aspartate aminotransferase activity was not observed on the other side, in the perikarya of the Purkinje cells of the related animals. However, there exists intense glutamic dehydrogenase activity. On the other hand, in the toad was not observed baskets with aspartate aminotransferase activity but this enzyme was presented on the other side in the perikarya of the Purkinje cells. All these observations have suggested the possibility that this special utilization of the glutamic acid is in some way concerned with the transmission phenomenons of the nerve impulse.

Animals↗
PubMed1976

[Histochemical study of the activity of aspartate aminotransferase in the spinal cord, the medulla oblongata and the central cerebellar nuclei of several vertebrates].

The aspartate aminotransferase activity (AAT) is reserched into the spinal cord, the medulla oblongata and the cerebellar nuclei of the rat, chicken, Lacerta lepida and Bufo calamitas. It's proved that the AAT activity shows in many locations, that are mainly: 1. In the nerve fibers 2. In the cytoplasmic membrane, and in the nuclear membrane of the neurons 3. In all neuronal cytoplasm, and 4. In the mitochondria of neurons and choroid plexus cells. The results base the idea that there's more than one pool of glutamic acid in relation to that AAT. It's suggested that the role that AAT plays is different in everyone of the described locations, and may be it's connected with transport phenomenons in the membrane, with energetic function on the mitochondria and with functions of the nerve impulse transmission in the synapsis. We remark, finally, the interest that the enzymatical works can have the time comming to establish homologies among similar structures of several animal's nervous system.

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