Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of the estrogen-like chlorinated pesticide chlordecone (Kepone) on sexual behavior was examined in proestrous rats following treatment with 25, 50, or 75 mg/kg chlordecone. In most animals, sexual behavior, both receptivity and proceptivity, was reduced within 60 min following the higher dosage of chlordecone. Reduced sexual receptivity occurred more slowly with 50 mg/kg chlordecone (usually within 180 min) and no reduction was seen following 25 mg/kg chlordecone. The reduced sexual behavior after chlordecone treatment preceded the onset of marked chlordecone-induced tremor. A group of rats treated with 75 mg/kg chlordecone was euthanized at the time that behavioral inhibition began to develop. The content of serotonin, norepinephrine, and their principal metabolites was determined by high-performance liquid chromatography of extracts of brain tissue of these animals. In hypothalamus, increases in serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) content, and a decrease in the level of norepinephrine (NE), were detected in chlordecone-treated rats relative to matched controls which received vehicle. The content of 5-HT was also increased in preoptic area of chlordecone-treated females. The content of the catecholamine metabolite, 3,4-dihydroxy-phenylacetic acid, was unaffected by chlordecone in either part of brain. These are the first observations of the parallel effects of chlordecone on receptive and proceptive behaviors, and on neurochemistry, in female rats; the results demonstrate short-latency effects of the pesticide treatment on the CNS events that mediate female reproductive behavior. Results of previous studies had led to the suggestion that chlordecone's inhibition of sexual behaviors resulted from its interaction with the intracellular estrogen receptor. However, the rapidity of the inhibition during the period of ongoing sexual behavior makes it unlikely that the inhibition is mediated by the pesticide's action at the intracellular estrogen receptor. Because of the importance of sexual behaviors to reproductive fitness, the current results indicate that nonsteroidal, behavioral mechanisms could contribute to chlordecone's neuroreproductive toxicity.
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PMID:Chlordecone (Kepone) on the night of proestrus inhibits female sexual behavior in CDF-344 rats. 171 37

46 postmenopausal women with estrogen receptor positive breast cancer entered a phase II study with a novel antiestrogen, toremifene. Patients had either recurrent or primarily inoperable advanced disease. No prior or concurrent cytostatic or hormonal treatment was allowed. Eight patients (17%) achieved complete response (CR), 17 (37%) partial response (PR) and 13 (28%) had stabilization of their disease at least for three months. The mean durations of responses were 52 +, 53 + and 27 + weeks, respectively, with 5 patients in CR, 6 in PR and 1 with no change (NC) still continuing the treatment. No significant differences could be seen in response rates according to the concentration of estrogen receptors or presence of progesteron receptors in this group of patients. Toxicity was not a problem, in general, the treatment was well tolerated. Two side effects (sweating and vertigo) were classified as severe and one patient after achieving PR interrupted the treatment because of tremor.
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PMID:Safety and efficacy of toremifene in breast cancer patients. A phase II study. 214 40

Ninety postmenopausal women with advanced breast cancer were randomly assigned to be treated with HD-MPA administered either by oral route (daily dose 900 mg) or by intramuscular injections (1 g IM daily X 5 q w during 4 consecutive weeks followed by maintenance with 1 g twice weekly). Among 78 evaluable cases, most heavily pretreated, remissions, lasting for a median duration of 11 months, were more frequent on oral (8/37 = 22%) than on IM therapy (5/41 = 12%). In both arms, high estrogen receptor levels and various clinical factors were associated with higher response rates i.e., age greater than 60, Karnofsky greater than 70, light prior systemic treatment. Side-effects, consisting mainly of weight gain, hypertension and tremor occurred with equal frequency on oral or IM treatment. Five patients complained of pain at the sites of IM injections. Thus, we recommended that, whenever possible, the oral route should be preferred. During the same study, in 20 patients (11 on oral and 9 on IM therapy), blood was drawn at 0, 30, and 60 days of treatment for the assessment of MPA and hormone levels. In both arms, at 60 days, comparable levels of circulating MPA were obtained, with a very significant drop of cortisol, androstenedione, and estrone. These endocrine results, together with our clinical data, indicate that HD-MPA therapy is active on estrogen-dependent tumors with the same specificity as that of other modalities aiming to suppress the adrenal function. Its antineoplastic action in humans could be ascribed at least in part to its suppressive action on the adrenals, resulting in a severe estrogenic deprivation in postmenopausal women.
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PMID:Oral versus intramuscular high-dose medroxyprogesterone acetate (HD-MPA) in advanced breast cancer. A randomized study of the Belgian Society of Medical Oncology. 294 41

Forty-six postmenopausal women with estrogen receptor positive advanced breast cancer were treated with the novel antiestrogen toremifene in this phase II study. The patients had no prior or concurrent hormonal or cytostatic treatment. Sixty milligrams of toremifene was given as a single daily dose for a minimum treatment period of 6 weeks. Eight patients (17%) achieved complete response, 17 (37%) partial response and 12 (26%) showed no change. The median durations of responses were 93, 66 and 24 weeks, respectively. Three patients still continue the treatment in complete response, four patients in partial response. No significant differences in response rates could be seen when related to different estrogen receptor concentrations. The treatment was well tolerated, only two patients had remarkable side-effects; one of the patients interrupted the treatment mainly because of tremor. Our conclusion is that toremifene is an effective, safe and in clinical practice easily applied choice of treatment in estrogen receptor positive advanced breast cancer.
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PMID:Toremifene, a new antiestrogenic compound, for treatment of advanced breast cancer. Phase II study. 296 65

Aqueous acetic acid was used to fix and store specimens of tissue prior to dissociation into nuclear suspensions for flow cytometric quantitation of DNA. The optimum concentration was 20 volumes of glacial acetic acid in 80 volumes of distilled water. Both neoplastic and benign nuclei were easily released from the fixed tissue blocks by slicing and shaking. Residual undissociated tissue was suitable for microscopic examination to confirm its identity. The nuclei fluoresced brightly after staining with propidium iodide, and yielded histograms similar to those from unfixed samples. Acetic-acid fixation resulted in slightly broader G1 and G0 peaks in the DNA histograms in comparison to unfixed cells, but fluorescent debris was less and correlation between the flow cytometric S-phase fraction (SPF) and in vitro thymidine labelling index (TLI) was better than with unfixed cells. Twenty-one of thirty-nine acetic-acid-fixed breast carcinomas had DNA indices in excess of 1.0 (increased nuclear DNA content in comparison to benign cells), and eighteen had DNA indices of 1.0 (normal or near-normal). The SPF was usually in excess of the TLI, but the two were significantly correlated (r = 0.72, P less than 0.0001). However, a significant correlation of SPF with TLI held only for the group with DNA index greater than 1.0. DNA indices greater than 1.0 were associated with high SPF and TLI, and high SPF and TLI each associated with low content of estrogen receptor.
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PMID:DNA flow cytometry of breast carcinoma after acetic-acid fixation. 669 73

Testis and ovary explants have been proposed as in vitro screens for identifying potential inhibitors of steroid biosynthesis. The goals of the current study were to optimize the conditions of the two assays, to characterize these assays using several compounds with well-defined endocrine activity, and to compare the responses from the explant assays with an in vivo male battery currently undergoing validation using the Crl:CD BR rat in order to evaluate their utility as test systems for screening unknown compounds for possible steroid biosynthesis inhibition activity. There were two components to the testis/ovary assays: ex vivo and in vitro. The ex vivo component used testes/ovaries from animals dosed with the test compounds in vivo, and the in vitro component used testes/ovaries from control animals. For the testis assays, decapsulated testis explants (50 mg) were placed into glass scintillation vials, +/-1.0 IU/ml hCG for 3 h in a shaking water bath (34 degrees C). Following the incubation period, medium was removed, centrifuged, and frozen until assayed for hormone concentrations. A similar procedure was used for the ovary explant assay except that each ovary was incubated separately. The testis explants were evaluated using the following compounds: ketoconazole (KETO), a testosterone biosynthesis inhibitor; aminoglutethimide (AG) (only in vitro) and anastrozole (ANA), aromatase inhibitors; finasteride (FIN), a 5alpha-reductase inhibitor; 17beta-estradiol (17beta-E2), an estrogen receptor agonist; flutamide (FLUT), an androgen receptor antagonist; ICI-182,780 (ICI), an estrogen receptor antagonist; haloperidol (HALO), a D2 receptor antagonist; and reserpine (RES), a dopamine depletor. In the ovary assay, AG (only in vitro), ANA, ICI, and HALO (only in vitro) were evaluated. Addition of fetal calf serum to the medium allowed measurement of estradiol (E2) in the testis assay, but production was not inhibited by ANA or AG. In the ovary explant assay, only AG was identified as inhibiting E2 production in vitro. Hence, both the testis and ovary explant assays appear to have limited utility for detecting aromatase inhibitors. Screening of these nine diverse endocrine-active compounds resulted in all of them being identified as altering the endocrine system when assessed by ex vivo and in vitro testis explants. Using only the in vitro assessment with the criteria of steroid biosynthesis inhibition, four of nine compounds were correctly identified in the testis explant assay (17beta-E2, KETO, FLUT, and HALO). The predictability of both the in vitro and ex vivo ovary assay was 50%, suggesting a 50% false positive or negative rate with unknown compounds. However, of the seven compounds assessed to date (17beta-E2, ICI, ANA, KETO, FLUT, HALO, and RES), all were correctly identified using an in vivo male battery, which also has the capability to detect other endocrine activities. Therefore, the testis and ovary explant assay would not be necessary if one were using an in vivo male battery, since this screen would identify steroid biosynthesis inhibitors and would also identify several other endocrine activities. Because of the difficulties in assessing cytotoxicity and the high false positive/negative rates, the ovary and testis explant assays are not useful as routine screening procedures for detecting steroid biosynthesis inhibitors; however, they may have utility in confirming in vivo findings.
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PMID:Ex vivo and in vitro testis and ovary explants: utility for identifying steroid biosynthesis inhibitors and comparison to a Tier I screening battery. 992 69

Parkinson disease is a neurodegenerative disorder caused by substantia nigra dopamine cell death and is characterized by bradykinesia, rigidity, rest tremor, and postural instability. Epidemiologic and clinical studies have suggested that gender and estrogen play a role in modulating Parkinson disease. The etiology of the estrogenic effect is unclear-it may be neuroprotective, symptomatic, or both. Retrospective studies suggest a possible neuroprotective role. Interventional studies have suggested a positive modulatory role or no role at all. While it is difficult to establish whether there is a true neuroprotective benefit of estrogen in the setting of even mild symptomatic benefit, laboratory data suggest such a neuroprotective role. Estrogen may act as an antiapoptotic agent, an antioxidant, or a neurotrophic modulating agent, promoting crosstalk with neurotrophic factors. The selective estrogen receptor modulators (SERMs) may also confer neuroprotection. However, prior to establishing the role of estrogen in Parkinson disease, additional study, including of the SERMs, is warranted.
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PMID:Estrogens and Parkinson disease: neuroprotective, symptomatic, neither, or both? 1277 7