Influence of phenylhydrazine on the antioxidant system of the erythrocytes and the liver in mice.

Phenylhydrazine when injected into the mouse acts in two phases. At an early stage it provokes directly in the erythrocytes as well as in the liver a decrease in the concentration of acid soluble nonprotein thiol groups. Indirectly it causes a later and more lasting increase in glutathione S-transferase and glucose-6-phosphate dehydrogenase activities in the erythrocytes, due mostly to a renewal of the population of these cells, and in glucose-6-phosphate dehydrogenase activity in the liver due to a decrease in hepatic glutathione.

[Modification of the antiradical defense system of the organism under the influence of the administration of a leukocyte factor in the rabbit. Its relation to the increase of radioresistance by biostimulants].

Injection in the rabbit of the leucocyte endogenous mediator (LEM) liberated by activated granulocytes provokes after 24 h an increase in the glutathione concentration, particularly in the spleen and in the kidney, as well as an increase in acute phase proteins and modifications of the zinc concentration in the plasma, the liver and the kidney. These modifications are compared with those provoked by non specific biostimulants which increase the radioresistance during periods varying from several days to several weeks. It may be that LEM or a component accompanying it in the injected fraction is a factor intervening in the increase in radioresistance caused by biostimulants.

[A simple and rapid method of studying the radiosensitizing ability of a drug in vivo by the study of hair dysplasia in the young mouse].

The study of radiation induced hair dysplasia in 8 day old mice allows investigations of the radiosensitizing power of a drug as early as the third day after irradiation without complicated equipment. The results being quantitative, they allow easy determination of the ER of a drug. In this study the method was applied to the action of metronidazol under anoxia.

[Influence of x-rays on depolymerization of lathyric collagen fibers reconstituted in vitro].

Irradiation of native collagen from lathyric rats in solution reduces the depolymerisation speed in the cold of fibres formed by gelification at 37 degrees C, rendering it thus comparable to the speed observed with normal collagen. In our test this normalisation does not appear if the collagen is irradiated in the state of gel. These observations and the absence of specific modifications induced by irradiation in the presence of reagents of the aldehydes speak in favour of the interference, on irradiation, of chemical groups different from the physiological aldehyde groups.