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Biomedical subjects

M C Boral

Publications and source records attributed to M C Boral.

At least 19 recordsLinked to original sources
PubMed1981

Body fluid and hematologic changes in the toad exposed to 48 h of simulated high altitude.

Body fluid and hematologic changes were found in three groups of adult male toads that had been exposed to 48 h of continuous simulated altitudes of 12,000, 18,000, and 24,000 ft, respectively. Erythrocyte counts and hematocrit ratios were increased significantly in all the high-altitude-exposed animals compared with the control group of animals kept at sea level, whereas the hemoglobin concentrations were significantly increased only in the 18,000- and 24,000-ft-exposed animals. Exposure to high altitude generally caused a reduction of plasma volume, blood volume, extracellular fluid volume, and total body water. These reductions were markedly lower in the animals exposed to 24,000 ft. These simulated high-altitude effects on body fluids and hematology in the toad (Bufo melanostictus) were compared with those of the rat, birds, and humans acutely acutely exposed at various high altitudes and were found to be qualitatively similar.

Altitude↗
PubMed1981

Studies on the erythropoietic effect of testis of toad at a simulated high altitude (hypoxic exposure).

Sham operated control toads (non castrated) have shown increased activity in regard to the hematological parameters in comparison to the castrated toads kept under simulated hypoxic condition. Injection of plasma from sham operated control toads exposed to hypoxic stimulation initiates erythropoiesis in starved toads, whereas plasma from castrated exposed to the same hypoxic stimulation failed to do so. It can be suggested that in toad, testis is the only organ responsible for controlling erythropoiesis by secreting certain substance in the blood, which acts as erythropoietic stimulating factor (ESF), and the production of this factor was found to increase in response to the hypoxic stimulation in order to combat under low atmospheric condition.

Altitude↗
PubMed1979

Studies on the erythropoietic effect of plasma from anemic toads both with and without testis.

Injection of plasma from experimentally induced anemic toad with intact testis increases erythropoiesis in starved toads evidenced by the increase of red blood cell, hemoglobin and hematocrit, whereas the plasma of castrated and phenylhydrazine-HCl treated anemic toad failed to do so. It can be suggested that the erythropoiesis stimulating factor (ESF) is produced from the testis of toad and the production of this factor (ESF) was found to increase during anemia in an attempt to correct the anemic condition.

Anemia↗
PubMed1976

Testicular histology in toad (Bufo melanostictus) following prolonged heat exposure.

A quantitative study of changes in the seminiferous tubule and the measurement of Leydig cell area were performed in the testis of toads exposed to 48 degrees C for 8 days. The frequency of occurrence of stages I and II was not affected whereas stages III and IV were influenced by the exposure to heat. The number of primary spermatocytes and secondary spermatocytes in stages III and IV were significantly decreased. The spermatocytes in stages III and IV were injured in the exposed toads. The area of Leydig cells including their nuclei was also decreased in the testes of heat exposed toads. It is concluded that the exposure to high temperature may have arrested spermatogenesis and affected Leydig cell function.

Animals↗
PubMed1975

Testicular delta 5-3 beta-hydroxysteroid dehydrogenase in toad (Bufo melanostictus) following prolonged exposure to heat.

In contrast to our previous observation of increased activity of testicular delta5-3beta-hydroxysteroid dehydrogenase in toad with relation to the moderate rise of external temperature (40 degrees C), the present observation, however, shows a significant fall of this enzyme in the testis of toads exposed to a considerably high temperature (48 degrees C). The possible mechanism of action of heat on testicular steroid hormone synthesis has been discussed.

Animals↗