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1.
Drug Chem Toxicol ; 41(3): 314-323, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29268635

RESUMO

Estrogen-progestin oral contraceptives (COC) or tobacco smoking has been associated with hypertension and endothelial dysfunction resulting in increased risk of cardiovascular diseases (CVD). Contrasting effects of nicotine exposure on endothelial function have been reported. The effect of non-smoking nicotine exposure on endothelial dysfunction during COC treatment remains to be fully elucidated. We therefore, sought to determine the effects of nicotine exposure during COC treatment on endothelial dysfunction mediators and circulating corticosteroids. Female Wistar rats aged 10 weeks were given (po) vehicle, nicotine (1.0 mg/kg) with or without COC steroids (1.0 µg ethinylestradiol and 5.0 µg levonorgestrel) daily for 6 weeks. Nicotine exposure caused 113.3% increase in insulinemia whereas COC treatment led to 76.9% increased insulinemia compared with control. Furthermore, COC treatment or nicotine exposure led to glucose deregulation, insulin resistance, reduced nitric oxide bioavailability, elevated plasminogen activator inhibitor-1, uric acid, oxidative stress, atherogenic dyslipidemia, and corticosteroids. However, COC + NIC treatment led to 41.2% decrease in insulemina compared with COC-treated rats. Furthermore, all other alterations were alleviated by nicotine exposure in COC-treated female rats with the exception of corticosteroids.


Assuntos
Corticosteroides/sangue , Anticoncepcionais Orais/toxicidade , Endotélio Vascular/efeitos dos fármacos , Hiperinsulinismo/prevenção & controle , Resistência à Insulina , Nicotina/farmacologia , Animais , HDL-Colesterol/sangue , Endotélio Vascular/fisiologia , Feminino , Óxido Nítrico/fisiologia , Ratos , Ratos Wistar
2.
Pharmacol Rep ; 69(3): 512-519, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28349880

RESUMO

BACKGROUND: Reports showed that estrogen-progestin oral contraceptive (COC) or tobacco smoking causes increased risk of cardiovascular diseases (CVD) in premenopausal women. Studies also suggest that nicotine, a major tobacco alkaloid, may worsen or improve atherothrombotic CVD. Altered hemorheology, prothrombotic and pro-inflammatory biomarkers, have been implicated in the development of atherothrombotic CVD events. However, the effect of non-smoking nicotine exposure on these biomarkers during COC treatment is not yet established. We therefore sought to determine the effects of nicotine exposure during COC treatment on these biomarkers, and also tested the hypothesis that the nicotine effects would be glucocorticoid-dependent. METHODS: Female Sprague-Dawley rats aged 10 weeks were given (po) vehicle, low-dose nicotine (0.1mg/kg) or high-dose nicotine (1.0mg/kg) with or without COC steroids (5.0µg/kg ethinylestradiol and 25.0µg/kg levonorgestrel) daily for 6 weeks. RESULTS: COC treatment or nicotine exposure led to increased insulin resistance (IR), hemorheological (blood viscosity, hematocrit and plasma viscosity), prothrombotic (plasminogen activator inhibitor-1), pro-inflammatory (uric acid, C-reactive protein, neutrophil/lymphocyte and platelet/lymphocyte ratios) biomarkers and corticosterone. However, these effects except that on corticosterone were abrogated by nicotine exposure during COC treatment. CONCLUSIONS: Our study indicates that nicotine- or COC-induced IR may be mediated via inflammatory/thrombotic pathway. The results imply that nicotine exposure could impact negatively on atherothrombotic biomarkers in COC non-users, whereas the impact in COC users could be positive. The results also suggest that the anti-inflammatory, antithrombotic and blood viscosity-lowering effects of nicotine exposure during COC use is circulating glucocorticoid-independent.


Assuntos
Anti-Inflamatórios/farmacologia , Anticoncepcionais Orais/toxicidade , Resistência à Insulina , Nicotina/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Viscosidade Sanguínea/efeitos dos fármacos , Anticoncepcionais Orais/administração & dosagem , Corticosterona/metabolismo , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Etinilestradiol/administração & dosagem , Etinilestradiol/toxicidade , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/farmacologia , Glucocorticoides/metabolismo , Levanogestrel/administração & dosagem , Levanogestrel/toxicidade , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Agonistas Nicotínicos/farmacologia , Ratos , Ratos Sprague-Dawley
3.
Environ Toxicol Pharmacol ; 43: 1-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26921793

RESUMO

The aim of the study was to analyze the effects of oral contraceptives (OCs) on pro/antioxidant status in the blood of healthy women aged 20-25 years. Individuals were divided into OCs users and OCs nonusers. Markers of oxidative stress in the blood such as Cu, Cu/Zn ratio, malondialdehyde (MDA), glutathione oxidized (GSSG), and gamma-glutamyl transpeptidase (GGT) were determined. Antioxidants such as glutathione reduced (GSH), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), glutathione S-transferase (GST), and superoxide dismutase (SOD) were estimated. Higher Cu concentrations, Cu/Zn ratio and GGT activity in women taking OCs were noted. A significant increase in MDA concentrations in oral OCs users was observed. Heightened activity of CAT in plasma was observed in OCs users, whereas SOD activity remained unchanged in plasma and erythrocyte lysate. A decline of GSH and GSSG in whole blood and glutathiono-dependent enzymes (GPx in plasma, GR in plasma and GST in lysate) was shown. Use of OCs leads to a pro/antioxidant imbalance. The results in the present study confirmed that GGT is an early marker of oxidative stress. Catalase is the main antioxidant, involved in the removal of free radicals in OCs users.


Assuntos
Anticoncepcionais Orais/toxicidade , Estresse Oxidativo/fisiologia , Adulto , Biomarcadores/metabolismo , Catalase/metabolismo , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Humanos , Malondialdeído/sangue , Superóxido Dismutase/metabolismo , Adulto Jovem , gama-Glutamiltransferase
4.
Curr Pharm Des ; 21(32): 4694-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26350526

RESUMO

Several medications are associated with retinal vascular toxicity. These include intraocular aminoglycosides, oral contraceptives, interferon alpha, several other agents, and talc, which occurs as a vehicle in some oral medications that may be abused intravenously. As a group, these entities represent a small but clinically relevant category of retinal toxicity from medications. Some of the manifestations (e.g., retinal vascular occlusion) are nonspecific, but others are more specific, including clinically visible talc emboli in retinal vessels. Toxicity may be asymptomatic or may cause irreversible visual loss. By maintaining a high index of suspicion, the correct diagnosis can usually be made.


Assuntos
Aminoglicosídeos/toxicidade , Anticoncepcionais Orais/toxicidade , Interferon-alfa/toxicidade , Vasos Retinianos/efeitos dos fármacos , Talco/toxicidade , Cegueira/induzido quimicamente , Humanos , Oclusão da Veia Retiniana/induzido quimicamente
5.
Psychoneuroendocrinology ; 54: 1-13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25679306

RESUMO

Ethinyl Estradiol (EE), a synthetic, orally bio-available estrogen, is the most commonly prescribed form of estrogen in oral contraceptives, and is found in at least 30 different contraceptive formulations currently prescribed to women as well as hormone therapies prescribed to menopausal women. Thus, EE is prescribed clinically to women at ages ranging from puberty to reproductive senescence. Here, in two separate studies, the cognitive effects of cyclic or tonic EE administration following ovariectomy (Ovx) were evaluated in young female rats. Study I assessed the cognitive effects of low and high doses of EE, delivered tonically via a subcutaneous osmotic pump. Study II evaluated the cognitive effects of low, medium, and high doses of EE administered via a daily subcutaneous injection, modeling the daily rise and fall of serum EE levels with oral regimens. Study II also investigated the impact of low, medium and high doses of EE on the basal forebrain cholinergic system. The low and medium doses utilized here correspond to the range of doses currently used in clinical formulations, and the high dose corresponds to doses prescribed to a generation of women between 1960 and 1970, when oral contraceptives first became available. We evaluate cognition using a battery of maze tasks tapping several domains of spatial learning and memory as well as basal forebrain cholinergic integrity using immunohistochemistry and unbiased stereology to estimate the number of choline acetyltransferase (ChAT)-producing cells in the medial septum and vertical/diagonal bands. At the highest dose, EE treatment impaired multiple domains of spatial memory relative to vehicle treatment, regardless of administration method. When given cyclically at the low and medium doses, EE did not impact working memory, but transiently impaired reference memory during the learning phase of testing. Of the doses and regimens tested here, only EE at the highest dose impaired several domains of memory; tonic delivery of low EE, a dose that corresponds to the most popular doses used in the clinic today, did not impact cognition on any measure. Both medium and high injection doses of EE reduced the number of ChAt-immunoreactive cells in the basal forebrain, and cell population estimates in the vertical/diagonal bands negatively correlated with working memory errors.


Assuntos
Prosencéfalo Basal/efeitos dos fármacos , Neurônios Colinérgicos/efeitos dos fármacos , Cognição/efeitos dos fármacos , Etinilestradiol/toxicidade , Transtornos da Memória/induzido quimicamente , Animais , Anticoncepcionais Orais/administração & dosagem , Anticoncepcionais Orais/toxicidade , Relação Dose-Resposta a Droga , Esquema de Medicação , Etinilestradiol/administração & dosagem , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344
6.
Neuroscience ; 181: 216-25, 2011 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-21334425

RESUMO

The greater incidence of myocardial infarction, cardiac arrest, and ischemic stroke among women who smoke and use oral contraception (OC) compared to women who do not smoke and who do or do not use OC may be due in part to how nicotine influences endocrine function in women. For example, we recently demonstrated that chronic exposure to nicotine, the addictive agent in tobacco smoke responsible for the elevated risk of cardiac arrest, abolishes the endogenous or exogenous 17ß-estradiol-conferred protection of the hippocampus against global cerebral ischemia (a potential outcome of cardiac arrest) in naive or ovariectomized female rats. In the current study we examined the hypotheses that (1) a synergistic deleterious effect of nicotine plus oral contraceptives exacerbates post-ischemic hippocampal damage in female rats, and (2) nicotine directly inhibits estrogen-mediated intracellular signaling in the hippocampus. To test first hypothesis and to simulate smoking behavior-induced nicotine levels in the human body, we implanted osmotic pumps containing nicotine in the female rats for 16 days. Furthermore, we mimicked the use of oral contraceptives in females by administering oral contraceptives orally to the rat. Rats exposed to either nicotine alone or in combination with oral contraceptives were subjected to an episode of cerebral ischemia and the resultant brain damage was quantified. These results showed for the first time that nicotine with oral contraceptives did indeed exacerbate post-ischemic CA1 damage as compared to nicotine alone in naive female rats. In ex vivo hippocampal slice cultures, we found that nicotine alone or with 17ß-estradiol directly hinders estrogen receptors-mediated phosphorylation of cyclic-AMP element binding protein, a process required for neuronal survival and also exacerbates ischemic damage. Thus, nicotine can affect the outcome of cerebral ischemia by influencing brain endocrine function directly rather than through indirect systemic effects.


Assuntos
Isquemia Encefálica/induzido quimicamente , Anticoncepcionais Orais/toxicidade , Estrogênios/toxicidade , Nicotina/toxicidade , Animais , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Moduladores de Receptor Estrogênico/toxicidade , Feminino , Agonistas Nicotínicos/toxicidade , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley
7.
Environ Sci Technol ; 45(1): 51-60, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20977246

RESUMO

Recent observed feminization of aquatic animals has raised concerns about estrogenic compounds in water supplies and the potential for these chemicals to reach drinking water. Public perception frequently attributes this feminization to oral contraceptives (OCs) in wastewater and raises concerns that exposure to OCs in drinking water may contribute to the recent rise in human reproductive problems. This paper reviews the literature regarding various sources of estrogens, in surface, source and drinking water, with an emphasis on the active molecule that comes from OCs. It includes discussion of the various agricultural, industrial, and municipal sources and outlines the contributions of estrogenic chemicals to the estrogenicity of waterways and estimates that the risk of exposure to synthetic estrogens in drinking water on human health is negligible. This paper also provides recommendations for strategies to better understand all the potential sources of estrogenic compounds in the environment and possibilities to reduce the levels of estrogenic chemicals in the water supply.


Assuntos
Anticoncepcionais Orais/análise , Estrogênios/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Animais , Organismos Aquáticos/efeitos dos fármacos , Anticoncepcionais Orais/toxicidade , Uso de Medicamentos/estatística & dados numéricos , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental , Estrogênios/toxicidade , Feminino , Feminização , Masculino , Praguicidas/análise , Medição de Risco , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade
8.
Endocr Pract ; 16(4): 554-60, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20150030

RESUMO

OBJECTIVE: To investigate the effect of the methanolic extract of seeds of Abrus precatorius on the estrous cycle, ovulation, and implantation of fetuses in Sprague-Dawley rats. METHODS: Cyclic female rats were randomly classified into 4 groups (A through D). Treated rats in group A had daily vaginal smears for a total of 64 consecutive days while being fed A precatorius extract for the first 32 of those days. Treated rats in group B received a single oral dose of the extract on the day of proestrus and were killed the following morning so that shed ova could be counted. Treated rats in group C received A precatorius extract from postcoital day 1 to 10 and were killed on day 12 to assess for anti-implantation effect, whereas the treated dams in group D received the extract from the 6th to the 19th day of gestation. The control animals in all 4 groups received an equal volume of distilled water. RESULTS: The methanolic extract of A precatorius caused a reversible disruption in the estrous cycle of the regularly cyclic rats and completely blocked ovulation in all the treated rats. Despite successful mating of the female rats with male rats of proven fertility, uterine dissection on postcoital day 12 revealed neither implantation nor resorption sites in all the animals treated with A precatorius. The extract of A precatorius caused a decrease in mean body weight, mean crown-rump length, and mean tail length of fetuses of the treated rats. CONCLUSION: There is a need to continue the search for new antifertility agents that have minimal side effects and widespread acceptability in addition to being reversible, affordable, and accessible. In this study, methanolic extract of A precatorius seeds caused reversible alterations in the estrous cycle pattern and completely blocked ovulation in Sprague-Dawley rats. In addition, the extract demonstrated anti-implantation activity and the potential to affect gross fetal morphometry in rats.


Assuntos
Abrus/química , Anticoncepcionais Orais/farmacologia , Implantação do Embrião/efeitos dos fármacos , Ciclo Estral/efeitos dos fármacos , Inibição da Ovulação/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Anticoncepcionais Orais/toxicidade , Estatura Cabeça-Cóccix , Feminino , Retardo do Crescimento Fetal/induzido quimicamente , Peso Fetal/efeitos dos fármacos , Metanol , Tamanho do Órgão/efeitos dos fármacos , Placenta/efeitos dos fármacos , Extratos Vegetais/toxicidade , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sementes/química , Cauda/efeitos dos fármacos , Cauda/embriologia
9.
Alcohol Clin Exp Res ; 26(8 Suppl): 70S-74S, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12198379

RESUMO

BACKGROUND: Oral contraceptives are widely used; however, these drugs occasionally cause liver injury. Recently, it was reported that estriol worsens alcoholic liver injury by the mechanism involving activation of Kupffer cells as a result of gut-derived endotoxin. However, the relationship between oral contraceptives and endotoxin-induced liver injury has not been elucidated. Here we show that oral contraceptives sensitize Kupffer cells via a mechanism dependent on increased gut permeability to endotoxin. METHODS: Female Wistar rats (200-250 g) were given intraperitoneally a combination of estradiol (35 ng/kg of 17 alpha-Ethynylestradiol) and progesterone (2 microg/kg of Norethindrone), each dose being similar to that contained in oral contraceptives (EP treatment). After 24 hr, a sublethal dose of lipopolysaccharide (LPS; 5 mg/kg) was injected via the tail vein. In some experiments, antibiotics (150 mg/kg/day of polymyxin B and 450 mg/kg/day of neomycin) were administered orally for 4 days before EP treatment. Gut permeability was measured in isolated segments of ileum by translocation of horseradish peroxidase. Kupffer cells were isolated and cultured in RPMI 1640 + 10% fetal bovine serum for 24 hr. After addition of LPS (100 ng/ml) to the culture medium, intracellular calcium concentration ([Ca2+](i) ) was measured with fura-2. RESULTS: Liver histology in rats given EP treatment intraperitoneally followed by an injection of LPS (5 mg/kg) 24 hr later revealed pronounced liver damage with massive necrosis. Whereas mean values of alanine aminotransferase (ALT) in the control, nontreated rats were 30 +/- 6 IU/liter, ALT increased to 75 +/- 21 IU/liter 24 hr after LPS injection. This increase was aggravated 6-fold (483 +/- 118 IU/liter; p< 0.05) by EP treatment. The EP treatment-induced increase in ALT was completely blocked by antibiotics (82 +/- 26 IU/liter; p< 0.05). Gut permeability was increased approximately 10-fold with EP treatment. This increase in gut permeability was not altered by treatment with nonabsorbable antibiotics. In isolated Kupffer cells, LPS increased [Ca2+](i) of Kupffer cells in control rats from basal levels (36 +/- 8 nmol/liter) to 100 +/- 8 nmol/liter. In contrast, the LPS-induced [Ca2+](i) elevation was approximately 3-fold greater in the group given EP treatment before 24 hr (305 +/- 17 nmol/liter; p< 0.05). This increase was also blocked completely by treatment with antibiotics (128 +/- 13 nmol/liter). Similar results were obtained for LPS-induced tumor necrosis factor-alpha production by Kupffer cells from either control or EP treatment group. The increased tumor necrosis factor-alpha production as a result of EP treatment was blocked completely by antibiotics. CONCLUSIONS: These results indicate that EP treatment in vivo sensitizes Kupffer cells to LPS via a mechanism dependent on the portal increase of gut-derived endotoxin. This event suggests that oral contraceptives exacerbate alcoholic liver injury.


Assuntos
Anticoncepcionais Orais/toxicidade , Escherichia coli , Etinilestradiol/toxicidade , Células de Kupffer/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Cirrose Hepática Experimental/patologia , Noretindrona/toxicidade , Animais , Sinergismo Farmacológico , Feminino , Células de Kupffer/patologia , Cirrose Hepática Alcoólica/patologia , Testes de Função Hepática , Ratos , Ratos Wistar
10.
Regul Toxicol Pharmacol ; 34(1): 53-61, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502156

RESUMO

For over 30 years various combinations of synthetic estrogens and progestins have been used in oral contraceptive formulations. Ethinyl estradiol (EE) and norethindrone acetate (NA) are common synthetic hormones used in oral contraceptives such as Loestrin, Brevicon, Ortho-Novum, Norlestrin, and Norinyl. In recent years these oral contraceptives have been considered for development in other therapeutic indications. Given the use of these agents for other clinical indications with different and larger target populations, an updated comprehensive review of the toxicology literature of estrogens and progestins is warranted. This review will summarize available data on the pharmacology and toxicology of estrogens and progestins with an emphasis on the specific synthetic hormones EE and NA. Ethinyl estradiol and norethindrone acetate alone or in combination, possess low acute and chronic toxicity. In some studies, EE and/or NA increased the incidence of specific tumors in susceptible strains of rodents and dogs, but not monkeys. These agents are not teratogenic when given in combination. Alone EE and NA have clastogenic properties. Overall, the animal data demonstrates that long-term exposure to EE and NA formulations pose very little health risks to humans.


Assuntos
Anticoncepcionais Orais/toxicidade , Etinilestradiol/toxicidade , Noretindrona/toxicidade , Animais , Animais de Laboratório , Cães , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Hormônios Esteroides Gonadais/fisiologia , Haplorrinos , Técnicas In Vitro , Camundongos , Mutagênicos/toxicidade , Neoplasias/induzido quimicamente , Noretindrona/análogos & derivados , Acetato de Noretindrona , Ratos , Especificidade da Espécie , Teratógenos/toxicidade , Testes de Toxicidade
11.
J Ethnopharmacol ; 74(2): 189-93, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11167037

RESUMO

An ayurvedic contraceptive--pippaliyadi vati, containing equal parts of powdered seeds or fruit berries of Embelia ribes, fruit of Piper longum and borax powder was fed orally to two groups of pregnant rats: 2.5 times to one and five times to the other; the recommended dose for humans. The foetuses of mothers fed with pippaliyadi had low birth weights and were smaller in length. The mothers gained less weight during gestation. Developmental defects of soft tissues and skeletons were analyzed. There were instances of herniation of the intestines into the umbilical cord in foetuses of mothers who were administered pippaliyadi. The control and the gum acacia groups did not show such herniation.


Assuntos
Anticoncepcionais Orais/toxicidade , Embrião de Mamíferos/patologia , Ayurveda , Extratos Vegetais/toxicidade , Teratógenos/toxicidade , Anormalidades Induzidas por Medicamentos/patologia , Animais , Peso ao Nascer/efeitos dos fármacos , Osso e Ossos/patologia , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Feto/patologia , Frutas/química , Hérnia Inguinal/induzido quimicamente , Hérnia Inguinal/congênito , Gravidez , Ratos , Sementes/química , Aumento de Peso/efeitos dos fármacos
13.
Toxicol Lett ; 104(1-2): 93-101, 1999 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-10048754

RESUMO

We investigated the effect of dienogest on bleeding time, coagulation, fibrinolysis, and platelet aggregation in female rats compared with that of medroxyprogesterone acetate (MPA) and danazol, in order to elucidate the reason for relatively high incidence of bleeding in dienogest-treated patients with endometriosis. Dienogest caused no change in the bleeding time at a single dose of 100 mg/kg or at a repeated dose of 10 mg/kg per day for 2 weeks. The drug increased the fibrinogen level, coagulation factor II and V activities, and antithrombin III activity, but had no effect on fibrinolysis or on platelet aggregation at repeated doses of 1 and 10 mg/kg per day for 4 weeks. MPA significantly shortened the bleeding time at the same doses as dienogest. MPA increased the fibrinogen level and plasminogen activity, potentiated the platelet aggregation, and increased the platelet cholesterol-to-phospholipid ratio at a repeated dose of 10 mg/kg per day for 4 weeks. Danazol significantly shortened the bleeding time like MPA. Danazol increased the fibrinogen level, coagulation factor II, V, VII, VIII, IX, X, XI, and XII activities, and antithrombin III activity, but had no influence on the platelet aggregation at repeated doses of 10 and 100 mg/kg per day for 4 weeks. In comparison with MPA and danazol, dienogest may induce a relatively high incidence of bleeding in patients with endometriosis partially because of its minimal effect on hemostasis.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Anticoncepcionais Orais/toxicidade , Fibrinólise/efeitos dos fármacos , Nandrolona/análogos & derivados , Agregação Plaquetária/efeitos dos fármacos , Animais , Tempo de Sangramento , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Colesterol/sangue , Danazol/farmacologia , Feminino , Lipídeos/sangue , Acetato de Medroxiprogesterona/farmacologia , Nandrolona/toxicidade , Fosfolipídeos/sangue , Ratos
14.
Arterioscler Thromb Vasc Biol ; 17(10): 1939-46, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9351357

RESUMO

In previous studies conducted in female rats and in women, oral contraceptives (OC) were found to induce a platelet hyperactivity that was related to an oxidative stress. Because cases of megaloblastic anemia have been reported to occur in women taking OC, these treatments are suspected of depleting folate stores. In the study presented herein, which was conducted in rats, we sought to determine the influence of dietary folic acid deficiency (FD) on the thrombogenicity of OC. Animals were fed for 6 weeks with either a folic acid-deficient diet (250 micrograms/kg folic acid) or a control diet (750 micrograms/kg). One-half of the animals in each group were treated with OC (ethinyl estradiol plus lynestrenol). FD and OC individually potentiated platelet aggregation in response to thrombin and ADP and the release and metabolism of arachidonic acid, in particular, the biosynthesis of thromboxane. These platelet activities were further enhanced in animals given both the folic acid-deficient diet and the OC treatment. In addition, FD enhanced the pro-oxidant state in OC-treated rats characterized by (1) a fall in platelet and plasma n-3 fatty acids, (2) an increase in plasma lipid peroxidation products such as conjugated dienes, lipid peroxides, and thiobarbituric reactive substances, (3) a rise in ex vivo erythrocyte susceptibility to free radicals. Moreover, we found that OC treatment led to a reduction of plasma and erythrocyte folate concentrations associated with a moderate hyperhomocysteinemia. Under our experimental conditions, we did not find significant synergistic effects between OC and FD. We propose that, although the untoward effects associated with the OC treatment may not primarily be dependent on FD, the folic acid deficiency magnified OC-induced oxidative stress, which resulted in platelet hyperactivity by elevating the pro-oxidant homocysteine plasma concentration. Despite the limitations of this animal model, the data of the present study suggest that in addition to cigarette smoking, inadequate folic acid intake might predispose those taking OC to vascular thrombosis.


Assuntos
Plaquetas/efeitos dos fármacos , Anticoncepcionais Orais/toxicidade , Deficiência de Ácido Fólico/sangue , Animais , Ácido Araquidônico/metabolismo , Plaquetas/metabolismo , Ácidos Graxos/sangue , Feminino , Radicais Livres , Homocisteína/sangue , Peroxidação de Lipídeos , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley
15.
Indian J Physiol Pharmacol ; 39(1): 63-7, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7705873

RESUMO

Trans-anethole was studied for antifertility activity in rats at dose levels of 50 mg, 70 mg and 80 mg/kg po. Dose-dependent activity was observed, a 100% anti-implantation activity being achieved at 80 mg/kg, po. The compound showed a significant estrogenic activity and did not possess anti-estrogenic, progestational, anti-progestational, androgenic or anti-androgenic activities. In an earlier study, the compound was found to be safe, its LD50 being more than 3000 mg/kg, po in mice.


Assuntos
Anisóis/farmacologia , Anticoncepcionais Orais/farmacologia , Fertilidade/efeitos dos fármacos , Aborto Induzido , Derivados de Alilbenzenos , Animais , Anisóis/toxicidade , Anticoncepcionais Orais/toxicidade , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Feminino , Dose Letal Mediana , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ovariectomia , Gravidez , Próstata/efeitos dos fármacos , Ratos , Glândulas Seminais/efeitos dos fármacos , Testosterona/farmacologia
16.
Am J Obstet Gynecol ; 160(5 Pt 2): 1280-5, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2719067

RESUMO

The effects on atherogenesis of stress, pregnancy, and oral contraceptive therapy were studied in a nonhuman primate model. The stress of social subordination was associated with ovarian dysfunction, unfavorable lipoprotein changes, and increased coronary artery atherosclerosis compared with nonstressed (socially dominant) or normal monkeys. Although pregnant animals exhibited lower high-density lipoprotein cholesterol concentrations, they had only one half as much diet-induced coronary artery atherosclerosis as their nonpregnant counterparts. Monkeys treated with an Ovral-like regimen also exhibited adverse lipoprotein changes. Nevertheless, prevalence and extent of coronary artery plaques decreased. We conclude that estrogen is an important factor in the animals' "female protection" against diet-induced atherosclerosis. We also suggest that the lowering of high-density lipoproteins by the progestin component of higher-dose contraceptives is not necessarily atherogenic if a sufficiently potent exogenous estrogen is administered concomitantly.


Assuntos
Anticoncepcionais Orais/toxicidade , Doença da Artéria Coronariana/etiologia , Prenhez/fisiologia , Estresse Psicológico/complicações , Animais , Colesterol/sangue , HDL-Colesterol/sangue , Modelos Animais de Doenças , Etinilestradiol/toxicidade , Combinação Etinil Estradiol e Norgestrel , Feminino , Macaca fascicularis , Norgestrel/toxicidade , Ovariectomia , Gravidez , Caracteres Sexuais , Meio Social
18.
Mutat Res ; 180(1): 115-20, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3627136

RESUMO

Wistar female rats were fed with oral contraceptives (OC, containing ethinylestradiolum and methylnorethrindronum) in early pregnancy. The dosage used for rats was 6.6 times more than the clinical dosage for humans in weight per kilogram. The SCE frequencies of liver and ovary cells and the changes of chromatin molecular composition in progeny of the rats fed with OC were observed. The results showed that the liver and ovary cells of newborns 12 h after birth exhibited increased SCEs value (liver: p less than 0.03; ovary: p less than 0.0004). These elevated SCE frequencies declined to the normal level about the 15th day after birth. The results for the quantity of nonhistone (NHP) and chromatin RNA in mother rats and their progenies also exhibited a significant increase, and declined to the normal level at the same period mentioned above. The results suggested that the high level of NHP and chromatin RNA may be induced by OC fed in early pregnancy and be maintained for some time after withdrawal of the OC pills. The changes of the chromatin molecular composition are perhaps somehow related to the increased SCE frequencies in the rat-liver cells. We suggest that the external steroids and their metabolites may activate more genes which were originally inactive and result in increased junctions between euchromatin and heterochromatin, resulting in more SCEs in quickly dividing embryo cells. The report here suggests that during early pregnancy the pills taken by women following OC failures may have a potential mutagenic effect on their progeny for some time after the pills have been stopped.


Assuntos
Cromatina/efeitos dos fármacos , Anticoncepcionais Orais/toxicidade , Prenhez/efeitos dos fármacos , Troca de Cromátide Irmã/efeitos dos fármacos , Animais , Animais Recém-Nascidos/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Fígado/ultraestrutura , Ácidos Nucleicos/análise , Ovário/ultraestrutura , Gravidez , Ratos , Espectrofotometria Ultravioleta
19.
Obstet Gynecol ; 70(3 Pt 1): 289-93, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3627576

RESUMO

The effect of postmenopausal estrogen use on mortality is an important and controversial subject. To address it, we analyzed data from a ten- to 13-year mortality follow-up of the 3437 women enrolled in the Walnut Creek Contraceptive Drug Study who never used either estrogens or oral contraceptives and the 2656 women who used estrogens but not oral contraceptives. By 1983, 109 estrogen users and 110 nonusers had died. After adjusting for age, mortality in estrogen users (1.64 per 1000 woman-years) was lower than in nonusers (2.06 per 1000 woman-years) for all categories of cause of death except cancer. The lower mortality from accidents, suicide, and homicide in estrogen users has no plausible biologic explanation, and the observation suggests that life-style differences between estrogen users and nonusers account at least in part for their lower mortality. On the other hand, the observation that the relative risk of mortality due to cardiovascular disease was 0.5 in estrogen users, after adjustment for age and other cardiovascular disease risk factors, is suggestive.


Assuntos
Estrogênios/toxicidade , Menopausa/efeitos dos fármacos , Mortalidade , Adulto , California , Anticoncepcionais Orais/toxicidade , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Risco , Estatística como Assunto , Fatores de Tempo
20.
Chest ; 90(3): 454-5, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3743165

RESUMO

A case of angiographically-documented embolism is presented in a patient using oral contraceptives (OC) with marked mitral valve prolapse (MVP) and an atrial thrombus. OC use has been shown to decrease levels of antithrombin III and increase platelet coagulant activity. This increased coagulability may increase the risk of intra-atrial thrombus formation and subsequent cerebral embolism in patients with MVP. We believe that MVP, especially when redundant valve leaflets are recognized, may be a relative contraindication to OC use.


PIP: A 21-year old women taking oral contraceptives suffered thromboembolic stroke associated with mitral valve prolapse. She had been using an unspecified oral contraceptive for 3 months postpartum, and had smoked a pack a day for 5 years. She complained of sudden right orbital headache, left-sided weakness and pain. Clinical exam showed left sided anopsia, facial paralysis, tongue protrusion, parietal sensory deficit, and loss of position sense. Computed tomography suggested a lesion near the right middle cerebral artery; and cerebral angiography revealed an 8 x 2 mm filling defect in that artery. A midsystolic click without a murmur was evident in the cardiac exam. Thickened, redundant mitral valve leaflets with marked prolapse, and a mass on the atrial side of the posterior leaflet appeared on the echocardiogram. The atrial thrombus was considered the source of the apparent embolism in the cerebral artery. Oral contraceptives have been found to increase the risk of thrombotic stroke and venous thromboembolism. Therefore, women with known mitral valve prolapse or leaflets may be advised not to use the pill.


Assuntos
Anticoncepcionais Orais/toxicidade , Embolia e Trombose Intracraniana/etiologia , Prolapso da Valva Mitral/complicações , Adulto , Ecocardiografia , Feminino , Humanos , Embolia e Trombose Intracraniana/diagnóstico por imagem , Prolapso da Valva Mitral/diagnóstico , Radiografia , Risco
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