Estradiol implants

Anterior hypothalamus (AH), estradiol implantation for vaginal marking behaviour, 233 Anthranilic acid, 155... 

Rufford J, Hextall A, Cardozo L, Khullar V. A doubleblind placebo-controlled trial on the effects of 25 mg estradiol implants on the urge syndrome in postmenopausal women. Int Urogynecol J Pelvic Floor Dysfunct 2003 14 78-83. 

McCue P M, Lemons S S, Squires E L et al 1996 Efficacy of progesterone/estradiol implants for suppression of estrus in the mare. In Proceedings of the 42nd American Association of Equine Practitioners Annual Convention, Denver, CO, pp. 195-196... 

By inducing anovulation with various hormonal therapies, the cyclicity of PMS disappears. Anovulation can be induced by estradiol implants, high doses of progesterones, OCs, GnRH-As, and danazol. For the perimenopausal syndrome, the replacement of hormones such as 17/S-estradiol, progesterone (if the uterus is intact), and testosterone is used to stabilize the deficiency and fluctuations in hormone levels. 

Robinson MR, Baffi J, Yuan P, et al. Safety and pharmacokinetics of intravitreal 2-methoxy-estradiol implants in normal rabbit and pharmacodynamics in a rat model of choroidal neovascularization. Exp Eye Res 2002 74 309-317. 

Suhonen SP, Allonen HO, Lahteenmaki P. Gynecology Sustained-release estradiol implants and a levonorgestrel-releasing intrauterine device in hormone replacement therapy. Am J Obstet Gynecol 1995 172 562-567. 

Very Htfle data are available regarding effects of anaboHc steroid implants on the Hpid metaboHsm in growing mminants. Lipogenic enzyme activity and fatty acid synthesis in vitro were elevated in subcutaneous adipose tissue from bulls implanted with estradiol (44), which may account for the increase in fat content of carcasses reported in some studies. TBA implants have no effect on Hpogenesis in intact heifers, and only tend to reduce Hpogenic enzyme activities in ovariectomized heifers (45). 

Another matrix diffusional implant consists of an outer layer of micronized, crystalline 17P-estradiol dispersed in siUcone mbber over a nonmedicated, cylindrical siUcone mbber core. The system, implanted subcutaneously in the ears of cattie, releases estradiol for up to 400 days with kinetics to improve growth rate and feed efficiency (83). 

Estradiol pellets (implants) contain pure crystalline 17 /J-estradiol and... 

Recently, a Japanese research group published preclinical safety and efficacy data of an oral antiestrogen (TZE-5323) (Saito et al. 2003). This drug has been shown to have a strong affinity for human ERa and ER/i and a dose-dependent capacity to inhibit estradiol-stimulated transcriptional activation (Saito et al. 2003). In the experimental endometriosis model in rats, TZE-5323 dose-dependently reduced the volume of the endometrial implant with an effectiveness similar to that of danazol and leuprorelin acetate without causing significant changes in bone mineral density and in serum estradiol levels (Saito et al. 2003). 

Fig. 14 ZK-253 effects on tamoxifen-resistant breast cancer xenograft tumours. Estrogen-dependent MCF-7/TAM tumours were implanted on day 0 into one flank of 70 estrogen-and tamoxifen-supplemented nude mice. After tumours had reached approximately 25 mm in size (after about 22 days), mice were randomised into seven groups (10 mice each) three control groups (control tamoxifen, control vehicle or control ovariectomy without estradiol), and the fom treatment groups (ZK-703, ZK-253, raloxifene or fulves-trant) each at 10 mg/kg subcutaneously daily. Treatment was continued either until the end of the experiment or imtil tumoms reached a median of approximately 100 mm (larger tumours were observed in some mice). The tumours were then removed, snap frozen, and used for analysis of ER levels, a Xenograft tumour growth curves. Data are expressed as medians with interquartile ranges, b ERa levels. Data are expressed as mean with upper 95% Cl...

Ethinyl Estradiol Norelgestromin (Ortho Evra) Etonogestrel subdermal Implant (Implanon)... 

Kaliwal, B. B. Efficacy of carrot seed Daucus carota) extract in inhibiting implantation and its reversal as compared with estradiol-17-beta in albino rats. J Curr Biosci 1989 6(3) 77—82. Lokar, L. C., and L. Poldini. Herbal remedies in the traditional medicine of the Venezia Giulia region (north east Italy). J Ethnopharmacol 1988 22(3) 231-239. 

Christensen, L.W, and Clemens, L.G. (1974) Intrahypothalamic implants of testosterone or estradiol and resumption of masculine sexual behavior in long-term castrated male rats. Endocrinology 95 984-990. 

Small doses of progestins administered orally or by implantation under the skin can be used for contraception. They are particularly suited for use in patients for whom estrogen administration is undesirable. They are about as effective as intrauterine devices or combination pills containing 20-30 meg of ethinyl estradiol. There is a high incidence of abnormal bleeding. 

Estradiol-17 is given to animals in form of a subcutaneous implant in the ear, alone or in combination with other hormonally active compounds such as progesterone or trenbolone acetate. Estradiol-17 is used in steers, to best advantage, but also exhibits some anabolic effects in heifers and veal calves. It works best in lambs in conjunction with androgens, but is not effective as an anabolic agent in pigs. It has been used in many forms in the past including the benzoate, dipropionate, hemisuccinate, heptanoate, propionate, undecanoate, and valerate esters. 

Estradiol-17 derived from an implant is indistinguishable from the endogenous esfradiol-17 in the circulatory animal s system. Following administration of radiolabeled estradiol-17 to calves, radioactivity in urine was mainly due to estradiol-17, with much lower amounts of esfrone. Apart of the free forms, both compounds were present as conjugates as well. Radioactivity in feces was primarily due to estradiol-17 and to estradiol-17 and estrone, each compound occurring in the nonconjugated form (1). 

Unlike in calves, the nature of the major liver metabolites was identified in steers the -o-glucopyranoside of estradiol-17 was found to be a major metabolite, whereas the 3- -o-glucosiduronate of estradiol-17 and other 17-glucosides of estradiol-17 and estradiol-17 were found to be minor ones (3). Residue depletion studies in steers implanted for 70-180 days with controlled-release implants containing 24 mg estradiol-17 showed that 24 h after implant removal the concentrations of residual estradiol-17 and estrone were 4.0 and 4.0 ppt in muscle, 5.0 and 4.7 ppt in liver, 7.5 and 7.1 ppt in kidney, and 7.1 and 14.3 ppt in the fat, respectively. These concentrations of residual estradiol-17 and estrone in the incurred samples were very close to those in the control tissues, which accounted for 5.8 and 4.8 ppt in muscle, 4.0 and 6.5 ppt in liver,... 

Progesterone is used primarily as a growth promotant in cattle in combination with estradiol or its esters. Administration is carried out by subcutaneous implant in the ear, which is subsequently discarded at slaughter. When administered exogenously, progesterone enters the same metabolic pathways and is indistinguishable from the endogenously produced compound. 

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