Norethindrone-induced masculinization and progeny testing in guppy, Poecilia reticulata (Peters 1859).

Norethindrone(NE) was evaluated for its efficacy on alteration of sex ratio of P. reticulata. Either the young fry or the brooders and the resultant fry were fed a commercial diet incorporated with NE at 0, 25, 50, 75 and 100 mg kg-1 diet (ppm) for 30-40 d in rectangular glass aquaria; this was followed by 40-60 d rearing on NE-free diet in out-door concrete tanks. In general, the androgen treatment altered sex ratio, leading to the production of a dose dependent increase in the percentage of males. The oral administration of the steroid at 75 ppm for 40 d or 100 ppmfor 30 or 40 d to first feeding fry, yielded 100% males. On the other hand, NE administration to brooders before parturition and the resultant fry also produced an all-male population of guppy. The sex ratio of the untreated control was almost 1:1. The survival of fish in all the trials was high, ranging between 67 and 100%. Mating masculinized males (“XX” male) with normal female resulted in an all-female progeny, while crossing normal male (XY) from treatment groups with normal female sired normal sex ratio (1:1), elucidating XX-XY sex determination system in the guppy.

Fine structure of prolactin cell of female albino rat as affected by some antifertility drugs--a comparative electron microscopic study.

One antioestrogenic compound as well as some antifertility drugs have been administered to female albino rats over a period of six months to study their long term effects on fine structures in PRL cell. Almost in all the cases, the dynamics of hormone synthesis and secretion have been affected. Fine structure is suggestive of activation of synthetic machinery of the cell. The cell picture under the estradiol valerate regimen presents a transitional stage progressing towards involution due to accelerated cell cycle. Sparse granulation, frequent granule extrusion and misplaced exocytosis under the influence of tamoxifen citrate or levonorgestrel + ethinyloestradiol are similar to those observed in adenomatous PRL cell. Fine structural correlates of stepped up synthesis are also observed following chronic progesterogenic influences of progesterone and norethisterone heptanoate, but the magnitude of the change is on a lower scale. All the fine structural changes have been discussed in the context of ultrastructural pathology.

Effects of norethisterone acetate and tamoxifen on serum prolactin levels, uterine growth and on the presence of uterine immunoreactive prolactin in estradiol-treated ovariectomized rats

The aim of the present work was to study the effects of the antiestrogen tamoxifen 9TAM) of progestin noresthisterone acetite (NA) and of their combination on serum prolactin levels, uterine growth and the presence of uterine immunoreactive prolactin estradiol- treated rats. Ovariectomized female Wistar rats were injected sc with estradiol valerate (VE, 50 µg/rat per week) or oil vehicle. During the secon week, estradiol-treated rats also received NA (0.12 or 1.0 mg/eat, sc, daily) or TAM (0.06 mg/rat) alone or in combination with NA (0.12mg). Serum prolactin levels were suppressed to the same extent in the TAM- and 1.0 mg NA-treated groups compared with rats given estrogen alone (2.3 ñ 0.3 and 5.6 ñ 1.5 ng/ml for TAM and NA groups vs 39.7 ñ 3.6 ng/ml for VE groups, P < 0.05). Except for the lowes dose of NA, uterine wet weight and DNA content were significant reduced in all groups compared to estradiol alone (236.8 ñ 18.0 and 295.6 ñ 27.8 mg vs 309.4 ñ 32.2 mg for uterine weight in TAM and NA groups vs VE, respectively, P 0.05; and 1.14 ñ 0.05 and 0.93 ñ 0.04 mg/uterus vs 1.33 ñ 0.06 mg/uterus for uterine DNA in TAM and NA groups vs VE groups). The combination of NA and TAM resulted in a higher degree of suppression of uterine growth than when each drug was used alone, indicating an additive antiproliferative effect of NA and TAM. Although no prolactin immunostaining was detected in the uterus of rats treated with estradiol, uterine immunoreactive prolactin was identified in those treated with NA, TAM ot both. These results suggest that an inhibitory effect on the action of estradiol can play a role in the hormonal modulation of uterine secretion

Effect of ethinyl estradiol and norethisterone acetate on adrenal and some other tissues of the rat

Alkaline phosphatase activity [AP] of the adrenal cortex of rats was determine under the effect of ethinyl estradiol [EE] and/or norethisterone acetate [NA], the two components of the contraceptive pill Gyn-Anovlar [Schering A.G. Berlin]. LA poathological study was also carried out to examine the effects of EE and NA on other tissues, mainly the liver, lungs, spleen and ovaries. EE in a dose of 10 micro/rat/day for 2 weeks caused a significant increase in the weight of the adrenal but no significant increase in the AP/gm cortical tissue. The 25 and 50 micro doses for the same period caused a significant increase in both adrenal weight and AP. When treatment was prolonged to 6 weeks no effect on adrenal weight or APO was detected. The same findings obtained with NA in a dose of 7 mg/rat/day for 2 weeks. The 14 mg dose of NA for the same period caused a significant increase in adrenal weight but no effect on AP. The 21 mg dose caused a significant increase in adrenal weight accompanied by significant decrease in AP/gm cortical tissue. Treatment with NA for 6 weeks caused a rise in adrenal weight and AP with the 7 mg dose, then a decline in AP with the 14 mg dose, and a decline in both adrenal weight and AP with the 21 mg dose. As regards the effects of EE and NA on other tissues, EE was found to have a powerful stimulatory effect on the reticulo-endo-thelial system [RES] as well as toxic effects on the liver. NA did not produce such lesions except with the large doses and prolonged periods of treatment. In addition NA produced cholestasis in the liver associated with staining of the liver cells with bile. Combination of EE and NA in the form of gyn-anovlar produced more powerful stimulation of RES and decreased the toxic manifestations of either component. As regards the ovaries, administration of 50 ug EE for 6 weeks produced profound hyperplasia of the granulose cells of the Graafian follicles and inhibited ovulation, however, NA did not inhibit ovulation. With gyn-anovlar, the effect of EE on the ovaries seemed to predominate and ovulation was inhibited

Effects of long-acting steroid contraceptives on ovarian and uterine histology of rats.

Subcutaneous injection of single doses (5 to 20 mg/kg) of DMPA or NE in virgin female rats caused reduction in number and diameter of CL, and increase in number of atretic and cystic follicles in the ovary. Histological examination of the endometrium of these animals showed low cubiodal cells with sparse distribution of low columnar cells, glands with atrophic changes and compact uterine stroma with or without patches of oedema. The results suggest regressive and atrophic changes in the ovary and endometrium.

Effects of norethisterone enanthate on certain body functions.

Effects of Norethisterone Enanthate (an injectable contraceptive) on body weight, blood pressure, blood cell count, level of haemoglobin, fasting blood sugar and serum cholesterol were studied in 31 women. It was observed that in the successful acceptors the pregnancy rate was nil. No appreciable change could be found in the body functions studied.