This section is from the book "Research In Physiopathology As Basis Of Guided Chemotherapy With Special Application To Cancer", by Emanuel Revici. Also available from amazon: Research In Physiopathology
Male and female rats, weighing approximately 250 grams, were injected with 5 cc. of 10% cholesterol only partially dissolved in a mixture of 3 parts oil and 1 part ether. The next day paraplegia with some ulceration of the hind legs was seen. Ulceration became accentuated in the following days. Curiously enough, this occurred only in the females. In repeated experiments in rats, and also in rabbits, guinea pigs and even mice, the same sex differentiation has been observed. Most of the female animals died from retention of urine as a principal complication of the paraplegia.
To investigate the nature of this sex difference, groups of males and females were castrated and spayed, then tested with the same cholesterol injection at various times from a few days to four months afterward. Castration had no influence in male rats; nor did the spaying of females reduce the incidence of paraplegia. The administration of 5 mgm. of testosterone daily for ten days to female rats, spayed or unspayed, also did not prevent the appearance of paraplegia after the injection of cholesterol in ether oil. The administration of 1/2 mgm. of stilbestrol daily for 10 days to males, castrated or not, did not break down their resistance to the cholesterol injection. However, the administration of the insaponifiable fraction of placenta or of the total body of rats, in doses of 2 cc. of a 5% solution in oil daily for ten days, made the males respond with paraplegia to the injection of cholesterol in ether oil solution. The administration to females, spayed or unspayed, of a 10% solution in oil of the acid lipid fraction of the same origin in doses of 2 cc. daily for ten days prevented this effect.
In collaboration with the late Prof. R. Leroux, Professor of Pathology of the Faculty of Medicine in Paris, we studied the influence exerted by sulfur mustard applied on the skin. The following technique was used: One drop of the pure substance was deposited on the external side of the ear pavilion of adult white rats, left in place for 10 minutes, and wiped off. A part of their ear pavilion was excised in a V form. The fragment so obtained was immediately processed through the special technique used for the extemporaneous examination of operatory biopsies. A longitudinal section of the pavilion was made in the frozen fresh material, and this surface treated first with formalin and then stained with scarlet red or black Sudan and hematein. The section was kept in water covered with a glass cover and immediately examined under incident light, using the Zeiss "Ultropak" dispositive. A water immersion objective was used for higher amplification. From the same material, fixed in formaldehyde at 10%, frozen and paraffin imbedded sections were also obtained.
In nontreated controls, except for the small fatty droplets in the cartilage cells themselves, the only fatty cells found were at the base of the pavilion. In the mustard treated animals, two or three layers of adipose cells were seen to appear beneath the treated skin, near the cartilage, around 20 minutes after the application of the sulfur mustard.
In our group of experiments, curiously enough, this phenomenon was seen to occur only in the treated female rats and not in the males. This difference in the response between males and females was not influenced either by castration or by treatment of the animals with sex hormones. It was induced in males however, by the administration of unsaponifiable fractions obtained from the total body of rats, or from human or cow placenta, and administered in doses of 1 cc. of a 10% solution in oil for at least one week prior to the application of sulfur mustard. In females, the appearance of adipose cells after the sulfur mustard applications was seen to be prevented, if the animals were treated daily for 10 days prior to this application with 2 cc. of a 10% solution in oil of lipidic acid fraction of human or cow placenta or of cod liver oil fatty acids.
Cultures of different ages of tetrahymena pyriformis in proteose peptone medium, were analyzed for the fatty acids present. The richness in fatty acids was seen to increase with the age of the culture, the old cultures being the richest.
In the changes related to old age, we have recognized a relationship between the amount of insaponifiable fractions and fatty acids present at different levels of the organization. A certain degree of opposite changes in two successive hierarchic levels can explain certain peculiarities found in the variations of sterols and fatty acids in old age.
In old rats we could establish that changes occur in two opposite directions between the cells and the metazoic compartment. Serum cholesterol amounts increase, as an increase of fatty acids and particularly polyunsaturated members occurs in the cells. The contrast between the two compartments becomes progressively more evident with old age. We tried to apply this data to the study of the relationship between the same compartments in humans. Instead of other cells, we analyzed red blood cells. In rats, rabbits and humans, the cholesterol in serum increases progressively with age but does not do so in the red cells. The amount of fatty acids in red cells is relatively increased with age at the same time as cholesterol content is decreased. The comparison between the cholesterol of serum and cholesterol of the red cells as well as fatty acid content of red cells seems to furnish information related to the progression of abnormalities of old age. This preliminary research, however, needs more confirmation.