Effect of Subacute Exposure to Lead on Responses to Estrogen in the Immature Rat Uterus

Effect of Prenatal Exposure to Lead on Estrogen Action in the Prepubertal Rat Uterus

“…It is similar to that reported following acute [13], subacute [12], or chronic [14] exposure to lead. In contraposition to findings in the uterine luminal epithelium, prenatal exposure did not cause a significant change in estrogen-induced hypertrophy in circular myometrium, an effect that was not found following chronic exposure either [14].…”

“…The interaction of lead with hormone action may be direct, via qualitative or quantitative changes in hormone receptors [15], or caused by changes in levels of other hormones that modify the action of sex steroids, such as glucocorticoids [16] and prolactin [17], hormones that increase under the effect of exposure to lead [18]. Further, in agreement with the existence of independent mechanisms of estrogen action in the uterus that are involved in the generation of separate groups of responses to hormone stimulation, and the report of differences in the regulation of estrogen action in each uterine cell-type [16, 19–23], it was reported that exposure to lead dissociates responses to estrogen in the uterus: it selectively enhances some of these responses, inhibits others while a third group remains unaffected [12–14]. …”

“…Among them, changes may occur at the enzyme levels [10, 11] or in the action of sex steroid hormones themselves, mainly estrogens, in the uterus [12–14]. The interaction of lead with hormone action may be direct, via qualitative or quantitative changes in hormone receptors [15], or caused by changes in levels of other hormones that modify the action of sex steroids, such as glucocorticoids [16] and prolactin [17], hormones that increase under the effect of exposure to lead [18].…”

“…In fact, we previously reported selective changes in some parameters of estrogen action following acute [13], subacute [12], or chronic [14] exposure to lead of prepubertal rats, which can be additionally explained in part by hematologic changes caused by lead [26] which, in turn, affect estrogen action in the uterus [16, 21, 27, 28]. …”

Human Exposure to Lead in Chile

“…In adults, chronic exposure to lead causes progressive damage to the central and peripheral nervous systems (Needleman et al 1979;Banks et al 1997), a moderate increase in blood pressure (Staessen et al 1994), and effects on both male and female reproductive systems in humans (Winder 1993) as well as in experimental animals (Ronis et al 1996;Tchernitchin et al 1998, causing mainly infertility and an increased abortion rate. It also affects the hematopoietic system (Grandjean et al 1989;Pagliuca et al 1990;Graziano et al 1991); for review of lead interference with the biosynthesis of heme, see NAS-NRC (1972).…”