RESUMO
Optimal conditions of pH, dose, time and temperature for the in vitro uptake of radioactivity from 3-H-E or 3-H-NE by the human endometrium and myometrium were established. Uptake was dependent on temperature but not on pH. Uptake of radioactivity from 3-H-NE was always higher (p smaller than 0.05) in both tissues than the uptake of radioactivity from 3-H-E at all the studied times but 10 minutes. Only the uptake of radioactivity from 3-H-NE by the myometrium increased continuously from 2 to 90 minutes. E2 increased the uptake of radioactivity from 3-H-E and decreased the one from 3-H-NE, being both effects more significant (p smaller than 0.05) in the myometrium. Both E and NE increased significantly (p smaller than 0.05) the uptake of 3-H-E2 by the myometrium but not by the endometrium. These results indicate that the interactions between E and NE and E2 are more marked in the myometrium. The uterine tissues studied corresponded to the secretory phase of the menstrual cycle, which was established by the endometrial histology and plasma levels of progesterone.
