Uterus, histology

Endosulfan administered by gavage at 1.5 mg/kg/day for 30 days to ovariectomized rats did not influence the relative weights or histology of the uterus, cervix, or vagina compared to ovariectomized control rats that did not receive endosulfan (Raizada et al. 1991). Rats in a positive control group received intraperitoneal injections of estradiol and showed increased relative organ weights and normal development of female reproductive tissues compared to the untreated ovariectomized control rats. 

Black et al. (1994) first reported that raloxifene was effective in terms of bone loss prevention and lipid pattern without any stimulatory effect on the uterus. Specifically, the histological examination of uteri from ovariectomized rats treated with raloxifene alone shows poor effects on myometrial thickness and a uterine weight slightly higher than untreated ovariectomized rats (Black et al. 1994). 

No studies were located regarding reproductive effects in humans after dermal exposure to disulfoton. In a 3-week study, in which disulfoton was applied to the shorn, unabraded skin of rabbits and left for 6 hours, 5 days/week, gross and histological examination of the testes, epididymides, ovaries, and uterus revealed no treatment-related lesions at <1.6 mg/kg/day (Flucke 1986). Slight... 

The vagina, uterus, and ovaries of all females and the seminal vesicles, prostate gland, right testis, right epididymis, and left caput epididymis of all males are preserved for possible histological examinations (1). Further examinations are only performed if a treatment-related effect on fertility is suspected. 

FIGURE 21.4 Histology of the uterus showing the endometrium and the myometrium. The perimetrium... 

No effects on reproductive performance or histological alterations in the ovaries, uterus, testis, or epididymis were observed in rats administered 0.075 mg/kg/day or less in a one-generation reproduction study (Bio/dynamics 1991 IRDC 1985). 

Male rats exposed for 2 weeks to a dust of 4-nitrophenol sodium salt at concentrations of up to 2,119 mg 4-nitrophenol/m showed no histological alterations in the testes and epididymides (Smith et al. 1988). Rats exposed to up to 30 mg 4-nitrophenol dust/m for 4 weeks showed no exposure-related effects on the gross or microscopical appearance of the prostate, seminal vesicles, ovaries, or uterus (Hazleton 1983). Nevertheless, since tests for reproductive performance were not conducted in these studies, reliable NOAELs for reproductive effects cannot be determined. 

No treatment-related effects were observed on testes weight, or on the histological appearance of the testes, ovaries, and uterus of rats administered up to 140 mg 4-nitrophenol/kg/day by gavage for 13 weeks (Hazleton 1989). However, since tests for reproductive performance were not conducted, a reliable NOAEL for reproductive effects cannot be determined. 

Female Sprague-Dawley rats were dosed by gavage with 0, 50,250, 500, or 1,000 mg/kg benzene daily on Gd 6-15 and killed on Gd 20 (Exxon 1986). No adverse effects were noted on reproductive competency. No histological changes were reported in the prostate, testes, ovaries, mammary gland, or uterus of male and female Fischer 344 rats and B6C3Fj mice dosed by gavage with up to 600 mg/kg/day benzene for... 

There also were no significant effects on ovarian or uterine weights, although histological examination of the ovaries (uterus not examined) from a small number of animals (three per group) suggested possible induction of ovarian atrophy by PCB 126. 

Progesterone induces characteristic morphological changes of the endometrium after estrogen-induced proliferation of this tissue. This effect is the basis of the endometrium transformation assay, in which immature rabbits are primed with estradiol for several days and are subsequently treated with a progestin, either by oral application or by subcutaneous injection. The proliferating response of the uterus is examined by histological analysis and quantitated with the McPhail index on a scale from 1 to 4, with 4 as maximal effect. The assay is very sensitive and specific, even if the rabbit expresses only the B isoform of PR. 

Figure 5.30 Illustration of the structure of epithelial tissue barriers in the body. Modified from [31] and Stedmann s Medical Dictionary. Epithelial tissues have a variety of histological patterns (a) simple squamous as found in the initial segments of ducts in glands and the alveolus (b) simple cuboidal as found in glandular ducts and ovary (c) simple columnar as found in stomach, intestines, uterus, and cervix ...

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