Biomedical subjects

P Castano

Publications and source records attributed to P Castano.

34 records · Page 2Linked to original sources

PubMed1982

Sciatic nerve fibres in albino rats after atrazine treatment: a morpho-quantitative study.

In this relation the authors present preliminary morpho-quantitative data on the fibres of sciatic nerves of normal albino rats, compared with those of animals treated endoperitoneally with 20 and 40 mg of atrazine. This compound (2 chloro - 4 ethylamino - 6 isopropyl amino-S-triazine) is largely used in agriculture, and recently was suspected to be neurotoxic in man. In order to evaluate its action on the peripheral and central nervous systems, and other organs, a morphological, morpho-quantitative and physiological investigation was planned on groups of untreated and treated albino rats. Our data are concerned with both unmyelinated and myelinated fibres. The areas, the shapes (and their distribution spectra), the perimeter and the possible anisothropy (as a sectioning plane index) of unmyelinated axons were evaluated. These parameters were compared in the groups (treated and untreated) by the usual statistical tests. The axonal and total areas, the thickness of the myelin sheath and the number of myelin lamellae of myelinated fibres were analysed, and the related distribution histograms were carried out. A comparison in the three groups was also made in this case. All the data, particularly those resulting from comparison among the groups, are discussed in terms of the possible neurotoxic action of atrazine.

Animals↗

PubMed1981

Carbon disulfide neuropathy in rats. A morphological and ultrastructural study of degeneration and regeneration.

The aim of this study was to elucidate the site and detailed nature of peripheral nerve damage induced in the rat by chronic CS2 inhalation exposure in the light of the relationship between pathological and neurophysiological data. Adult male rats were exposed to 700 ppm of CS2 2 h/d, 5 d/week for 12 weeks and then followed-up for 18 weeks. The first alteration observed was a decrease in the nerve conduction velocity, discovered after only 3 weeks of exposure. Pathological lesions were first observed in the 10th week and consisted of a typical "giant axon" axonopathy. Obvious pathological lesions of the myelin sheaths were revealed much later, in the 3rd week after the end of exposure, when some nerve fibers were dying back. Recovery took place with the regeneration of new fibers which started in the 8th week after the end of exposure and was nearly complete in the 18th week. These findings demonstrate that CS2-induced polyneuropathy is an axonopathy very similar to that caused by other occupational neurotoxic agents like MnBK, n-hexane, and acrylamide. The timing of the pathological events within the nerve fibers suggests that the pathogenesis of the nerve lesions should probably be attributed to a primary energy failure of the axonal membrane induced by CS2.

Animals↗

PubMed1981

Effects of ganglioside therapy on experimental CS2 neuropathy.

Both in animals and in man the inhalation of CS2 vapor induces a chronic polyneuropathy with primary lesions in the axons of peripheral nerves. Since it was reported in several studies that the administration of gangliosides improves nerve regeneration and the functional recovery of nerves damaged by section as well as cryodegeneration, a study was undertaken to evaluate the effects of bovine-brain gangliosides administration on the experimental CS2 neuropathy in the rat. One hundred and fifty male rats were intoxicated with CS2 by a discontinuous inhalation exposure to 700 ppm for 12 weeks until a clear neuropathy developed. Thereafter the animals were subdivided at random into five groups and treated in different ways: 10 mg/kg BW gangliosides, 0.5 mg/kg gangliosides, 0.5 mg/kg vitamin B1, and 1 mg/kg vitamin B6, physiological solution, and controls without any treatment. The recovery from neuropathy was controlled for 18 weeks of treatment and assessed periodically by means of clinical, electromyographic, and morphological examination. The results of morphological studies showed more pronounced regeneration activity in the rats treated with the high dose of gangliosides than in all others, while no differences among the groups could be observed as far as clinical and neurophysiological parameters are concerned. The mechanism supporting this ganglioside-induced effect has so far not been ascertained, and further studies on this subject are in progress.

Animals↗

PubMed1976

Ultrastructural aspects of Peptichemio action on mouse sarcoma 180.

The electron microscope study of the cellular elements originating from mice experimental tumours (sarcoma 180) treated and non-treated with Peptichemio showed alterations of the nuclear and cytoplasmic structures in the animals treated. The data herein accord fully with the results obtained by other histological, biochemical and biomolecular techniques and make it possible once again to lay stress on the double alkylating and antimetabolic action of this antitumour drug, very likely taking place simultaneously both at nuclear and cytoplasmic level.

Animals↗

PubMed1973