Lipoperoxide concentration in erythrocytes from workers occupationally exposed to lead (mean blood lead concentration 57.1 (SD 17.6) micrograms/dl) was significantly higher than that in controls. It was not different in plasma from the two groups. The activity of superoxide dismutase (SOD) and catalase in erythrocytes from workers exposed to lead was significantly lower than that of control subjects. The effect of lead was also seen in the glutathione concentration of erythrocytes from lead exposed workers, which was reduced to 69% of that found in erythrocytes from control workers. The increase in methaemoglobin content of erythrocytes from workers exposed to lead was less than expected and not significantly different from that of controls. A positive correlation between lipoperoxide concentration in erythrocytes and lead concentration in blood and a negative correlation between glutathione concentration in erythrocytes and blood lead concentration were found. Incubation of erythrocytes for 24 hours at 37 degrees C in the presence of lead (100 micrograms/dl) produced no changes in glutathione and lipoperoxide concentrations, although there was inhibition of activity of SOD (14.3%), catalase (10.1%), and glutathione peroxidase (35.1%). A similar experiment with heparinised whole blood showed increased haemolysis with no changes in membrane lipid peroxidation of erythrocytes. It is postulated that the lowered concentration of glutathione and decreased activity of SOD, catalase, and glutathione peroxidase in erythrocytes from workers exposed to lead may play a part in the increased membrane lipid peroxidation. Furthermore, the results suggest the possibility that leucocytes, or platelets, or both, may induce haemolysis in the presence of lead.
UCHIDA et al. December 1970 Endocrinol. Japon. initial half of pregnancy is sustained by hypophyseal factors, but that the one in the latter half of it by placental or uterine luteotrophic substances. Two peaks of progesterone secretion during pregnancy noted by Fajor and Barraclough (1967) may represent the actions of both luteotrophins from different origins. In the present experiments, ovarian progesterone and 20ƒ¿-OH-P secretions were measured in detail during pregnancy and pseudopregnancy in relation to the changes in corpora lutea weight, 20ƒ¿-hydroxysteroid dehydrogenase (20ƒ¿-OH-SDH) activity, cholesterol and both progestin concentrations in corpora lutea, since cholesterol (Everett, 1947) and 20ƒ¿-OH-SDH activity (Wiest et al., 1968) in corpora lutea are known to be related to luteal function. Meterials and Methods Animals Wistar strain female rats weighing 170 to 200g were reared with an ordinary rat chow and water ad
Seven 19-norsteroids, 17a:-ethinyl-19-nortestosterone (I), 17a-ethinyl-5(10)estraenolone (II), 17a-ethyl-19-nortestosterone (III), 17a-methyl-19-nortestosterone (IV), 17a:-propyl-l9-nortestosterone (V), 17a-butenyl-19-nortestosterone (VI), and 17a-allyl-19-nortestosterone (VII), and two progesterone derivatives-17a-hydroxyprogesterone-17-acetate (VIII) and 17a-hydroxy-6a-methyl-progesterone acetate (IX) have been administered subcutaneously or orally into Clauberg rabbits to demonstj-ate their progestational activity by estimation of endometrial carbonic anhydrase content and measurement of the uterine G/M ratio.The increase of endometrial carbonic anhydrase content induced by treatment with each compound correlates well with that of the G/M ratio which measures uterine proliferation. Similarly, the relative potencies by the enzyme test correspond to those obtained by the G/M assay either in subcutaneous treatment or in oral administration.The relationship between the progestational activity and the length of .17side-chain in the 17-substituted-19-nortestosterones found by Saundcrs et al.(3) seems to be applicable to the potencies obtained by subcutaneous injection but not to those found on oral administration. Among the 17-substituted-19nortestosterones, the allyl-compound is the most active in the subcutaneous assay, but the most active by oral route is the ethyl-compound.Three 19-norsteroids, I, II and IV are much more active by the oral route than by the subcutaneous route, while the others are quite opposite. The progestational activity of progesterone administered either parenterally or orally is increased by 17a-acetoxylation ; and further increase is obtained by 6a-methylation of this acetate ester.
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