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1.
J E Creange  G O Potts 《Steroids》1974,23(3):411-420
A method is described for the radioligand assay of circulating levels of a novel, pituitary gonadotrophin inhibiting agent, danazol (17α-Pregn-4-en-20-yno[2,3-d]isoxazol-17-ol). The assay described is based upon the ability of danazol to bind avidly to pregnant guinea pig plasma proteins, a binding system hitherto considered highly specific for progesterone. Danazol is separated from progesterone and other possible interfering substances by paper chromatography. The method was used to measure danazol in a series of normal human subjects given the drug at 800 mg/day.  相似文献   

2.
Chronic administration of Danazol (25 mg/kg body wt) caused lesions in the testes of Rattus rattus Rufescens. Depletion of spermatocytes, spermatids and spermatozoa was conspicuous. Impairment of Leydig cell function was correlated with reduced cell size and depressed accessory sex organ weights. Epididymal cell height was greatly reduced. The lumen was devoid of spermatozoa. Danazol administration inhibited the synthesis of RNA, protein, sialic acid in the testes and accessory sex organs. Total cholesterol of the testes was increased, whereas the acid phosphatase enzyme activity was reduced. Testosterone propionate did not enhance the growth of accessory sex organs in castrated rats receiving Danazol. In conclusion, Danazol inhibits the system of steroidogenesis and spermatogenesis in Rattus rattus, when treated chronically for a period of 40 days. These effects are reversible after 60 days of cessation of drug administration.  相似文献   

3.
Bone injury inflicted at varying time intervals during 24 hr day-night cycle caused significant varying increase in plasma 17-OHCS levels in all traumatized animals and the levels remained elevated up to 24 hr after trauma. The level of plasma 17-OHCS was found to be aberrated in all the traumatized animals. Thus, adequate adrenocortical response to trauma and aberration in the adrenocortical secretory activity appears inevitable irrespective of the time at which the trauma is produced. However, the degree of response depends on the particular time at which the trauma is inflicted.  相似文献   

4.
Adult male Wistar rats were treated with Danazol (4 mg/day s.c.) for 52 days. The drug produced a marked, rapid drop in serum testosterone concentrations to very low levels and caused a slower decrease in serum FSH, LH and testis weight. Flow cytometric analysis of testicular cell suspensions showed a decline in the absolute numbers of haploid cells (spermatids), tetraploid cells (mainly pachytene spermatocytes) and of cells in the S-phase of the division cycle, suggesting that Danazol inhibited proliferation of spermatogonia and/or primary spermatocytes. Histological counting of the different types of spermatogonia, however, revealed no significant change in their numbers during Danazol treatment. It is concluded that Danazol inhibited spermatogenesis primarily after the preleptotene stage of primary spermatocytes.  相似文献   

5.
The growth features of cells from endometriomas biopsied from patients who had been treated with Danazol or with hormones have not been studied in vitro. Danazol is a versatile drug and despite its recognised efficacy in controlling endometriosis, little is known about is cytotoxicity and mechanism of action. Culture of the biopsied endometriomas permitted qualitative cytotoxic assessments by way of comparison with cultured normal uterine endometrial cells treated in vitro with Danazol. The growth characteristics were studied in monolayer and collagen gel cultures. Cytopathology was characterised by light and electron microscopy. Since endometriosis is associated with infertility in women, data from in vitro fertilisation (IVF) were analysed with respect to treatment modalities as compared with cases suffering fallopian occlusion. Danazol reduced pregnancy chances. Two factors may be responsible: (a) altered follicle development resulting in poor oocyte quality (b) reduced nidation because of long-lasting endometrial cytotoxicity. The experimental findings reported here support the latter explanation. Consequently, Danazol therapy should be conditional; patients wishing to achieve pregnancy should preferably receive hormonal therapy.  相似文献   

6.
17beta-Hydroxysteroid dehydrogenase type 1 (HSD17B1) is a key enzyme of 17beta-estradiol biosynthesis, which might play an important role in follicular development of the ovary. In this study, we isolated the complete coding sequence of porcine HSD17B1 gene and its unique intron sequences of porcine HSD17B1 gene, identified a single nucleotide polymorphism (SNP: A/C) in intron 4, and developed a PCR-MvaI-RFLP genotyping assay. Association of the SNP and litter size was assessed in two populations (purebred Large White and a experimental synthetic Line (DIV) sows). Statistical analysis demonstrated that, in the first parity, AC animals in experimental synthetic Line (DIV) sows had 0.52 more piglets born compared to the CC animals (P<0.05). In the all parities, pigs with the AA genotype had an additional 1.11 and 0.96 piglets born alive compared to the CC animals (P<0.05) in both experimental synthetic Line (DIV) and purebred Large White, respectively. Experimental synthetic Line (DIV) sows inheriting the AC genotype had additional 0.84 piglets born alive compared to the CC animals (P<0.01) in all parities. In addition, significant additive effect of -0.55+/-0.24 piglets/litter and -0.48+/-0.22 piglets/litter on piglet born alive was detected in both experimental synthetic Line (DIV) sows and purebred Large White lines (P<0.05), respectively. Therefore, HSD17B1 gene was significantly associated with litter size in two populations and could be a useful molecular marker in selection for increasing litter size in pigs.  相似文献   

7.
The acute phase response is an important adaptive response to sepsis and injury. As anabolic steroids increase protein synthesis we postulated that these agents might also increase hepatic acute phase protein synthesis. Male Wistar rats were pretreated with testosterone or danazol for 48 h prior to caecal ligation and puncture (CLP). Thirty-six h following surgery the animals were killed and blood taken for full blood count, total protein, albumin, alpha, beta and gamma globulin fractions on serum electrophoresis, complement C(3) and transferrin levels. Danazol increased the alpha1, alpha2 and beta1 globulin serum protein fractions in comparison with no surgery and CLP alone groups. These results indicate that danazol increases plasma acute phase proteins, as measured by electrophoresis, in this model of intra-abdominal sepsis.  相似文献   

8.
Poor reproductive performance of the squirrel monkey (Saimiri boliviensis boliviensis) in captivity and a relative progesterone (P) deficiency in pregnancy have been reported. Since premature births may contribute to pregnancy wastage, we attempted to measure the effectiveness of 17-hydroxyprogesterone caproate (17-OHPC) treatment of pregnant squirrel monkeys to prevent early deliveries. Based on clearance studies of nonpregnant animals, 25 mg of 17-OHPC was administered at 6-day intervals to a test group of 31 pregnant monkeys while the control group of 29 received saline. Venous blood was obtained at 6- to 12-day intervals for measurement of 17-hydroxyprogesterone (17-OHP), P, 17-B estradiol (E), and androstenedione (A), and dihydroepiandrosterone (DHEA) levels by radioimmunoassays. The treated group had a significant increase in serum 17-OHP (P < 0.001), P (P < 0.01), and DHEA (P < 0.05) levels compared to controls. The numbers of live births, stillbirths, or neonatal deaths did not differ significantly between groups. Although 17-OHPC administration appeared to increase P and 17-OHP levels, this did not alter the duration of pregnancy nor delay the onset of labor. A significant fall in 17-OHP, P, and E levels was observed 6–12 days before delivery.  相似文献   

9.
Oocyte diameters and their frequency distribution, and various other data determined for the oestradiol-17 β treated female specimens of Asterias rubens proved to be significantly different from those for the control animals. The maturation index of the treated animals is 2.4, that of the control animals 1.4. Since the treated animals show a greater heterogeneity in development than the control animals, and because the diameter of the smallest oocytes is the same for both treated and control animals, a threshold size of the oocytes may be required before oocyte growth can be stimulated by oestradiol-17β, and before substances originating in the pyloric caeca are incorporated into the oocytes. Oestradiol-17β treatment caused a tenfold increase of the oestrone level in the ovaries, whereas a non-significant increase was observed in the pyloric caeca. This may indicate that in vivo oestradiol-17β is converted into oestrone in the ovaries but not in the pyloric caeca.  相似文献   

10.
Presence of 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) in testes and ovaries of the common mussels--Patinopecten yessoensis (Jay) and Crenomytilus grayanus (Dunker) has been demonstrated histochemically. The enzyme is revealed in some granular amebocytes and germ cells. In growing oocytes its activity is higher that in oocytes completed their growth. 17 beta-HSD is revealed electron microscopically near agranular endoplasmic reticulum, or on the external surface of its membranes and in globules, possessing, evidently, lipid nature. The data obtained demonstrate that synthesis and metabolism of steroid hormones are possible both in additional gonadal elements and in germ cells of the animals investigated.  相似文献   

11.
In contrast to the situation in adults, desensitization of androgen production, secondary to loss of enzyme activity, was not found in testes of neonatal rats exposed to human Chorionic Gonadotropin (hCG). In the present study attention was given to the acute effects of a single injection of hCG upon the activity of testicular 17 alpha-hydroxylase, C17,20-lyase and the concentration of testosterone in the serum of 5, 10 or 28-30 day old rats was investigated. Tritiated H2O from 17 alpha-[3H]progesterone and 14CH3COOH from 21-[14C]progesterone were the products measured to evaluate hydroxylase and lyase activities respectively. Large increases in hCG in the serum were detected within 2 h of a subcutaneous injection. Testosterone, which was highest in 5 day animals, increased quickly in all animals given hCG. In 28-30-day old animals, the concentration of this steroid began to fall 24 h after injection of hCG. 17 alpha-Hydroxylase activity decreased in the testes of all animals given hCG, but only after a brief increase. Activity returned to the starting level, or above, within 24 h in 5 or 10-day old animals. In 28-30-day old rats the activity of both enzymes decreased dramatically to a nadir at 24 h, but increased thereafter. The results indicate that desensitization of testicular androgen synthesizing enzymes occurs in neonatal as well as older testes stimulated with hCG, but the desensitization was very brief in neonatal animals and no desensitization of lyase was found in 5-day old rat testes.  相似文献   

12.
13.
Saint-Vallier (Drôme, France) is the biostratigraphical reference locality for the biozone MN17 (Upper Pliocene, between 2.4 and 1.9  Ma). The taphonomic study presented here is based on the results of a recent 6-year campaign of renewed study. Carefully controlled excavations allow the study of the relative position of remains and their orientation inside several fossil clusters. Flowing water is the most likely agent responsible for fossil orientation: bones of the animals were carried by water from distal to proximal areas of deposition, where they were quickly buried by sediments. Taphonomic clues suggest that the causes of mortality were attritional. The study of mortality profiles yields more ambiguous results although not necessarily in contrast with the attritional hypothesis. Such a study shows the importance of the sample size for the interpretation of the age diagrams.  相似文献   

14.
Following a 40-day acclimatization period, 12 cyclic beef heifers entered a 95- to 101-day test period. Prior to fenprostalene treatment, all animals were studied through two normal estrous cycles. Plasma samples were obtained daily from all animals during the course of the study and were assayed for estradiol-17beta and progesterone. Group 1 heifers (n=6) were then treated with fenprostalene at mid-cycle during two subsequent cycles. This treatment was accomplished by treating the animals 11 days after the first clinically observed signs of estrus following Study Day 21 and treating them again 11 days later. Each treatment consisted of a subcutaneous injection of 1.0 mg fenprostalene. The animals were studied through two or three estrous cycles following the second injection. The Group 2 animals (n=6) were maintained as untreated controls through a corresponding period. Fenprostalene induced estrus in five of six treated heifers within 5 d following the first injection and in five of six heifers within 3 d following the second injection. The mean time to estrus was 3.4 d (+/- 1.1 d SD) following the first injection and 2.2 d (+/-0.8 days SD) following the second injection. No significant differences were found in the plasma levels of estradiol-17beta and progesterone when comparing fenprostalene-induced cycles to those that occurred naturally. The fenprostalene injection reset the estrous cycle without changing the nature of the cycle. The time of clinically detected estrus usually coincided with a sharp peak in estradiol-17beta concentration.  相似文献   

15.
We have studied the effects of wild-derived (Rb7) and laboratory-derived (Rb1) Robertsonian translocations involving chromosome 17 on t-complex determined transmission ratio distortion and crossing-over suppression in mice. The Rb7 chromosome is significantly unlike all other wild-type chromosome 17s tested, while Rb1 is not. t0/Rb7 males are uniformly extremely high distorters (greater than 96 percent) while th2/Rb7 males are uniformly extremely low distorters. t0/Rb7 animals allow genetic recombination in the centromere to t-lethal region interval. These observations could be explained if the Rb7 chromosome contains one or more t-like regions.  相似文献   

16.
Two experiments, each using 8 animals, were conducted in the non-breeding and breeding seasons, respectively, and each animal was injected with 4 different doses of oestradiol benzoate over 4 trials. The resulting physiological concentrations of plasma oestradiol caused depression of both LH and FSH values. The highest dose elicited a biphasic response in LH with a pulse-like surge at 24 h after injection. There was no significant difference between the response of either hormone at the two times of the year and it is concluded that, in tammars, there is no seasonal difference in the responsiveness of the hypothalamus/pituitary to the negative feedback effect of oestradiol.  相似文献   

17.
In this study the risk of photochemotherapeutic dose levels of long wave ultraviolet radiation (UVA) was assessed by employing a laboratory animal system, C17 brown mice. The experimental group was subjected to three UVA dose levels, 1000, 2000 and 3500 J/cm2. The dose regimen 50 J/cm2 per day for five days a week was completed in 4, 8 and 14 weeks respectively. The UVA exposed animals were examined until 52 weeks post UVA exposure periods for morphological lesions. Estimations of DNA, protein levels and dermal, epidermal thickness were made. There were no lesions observed with the highest UVA dose employed. Alterations in the DNA and protein levels in the skin of animals in the exposed groups were observed in the post UVA periods. A notable increase in the DNA level was observed 47 weeks post UVA period. The significance of alterations in DNA and protein levels needs to be studied further for evaluation of long term risk following UVA exposure. The data presented however led to a conclusion that the photochemotherapeutic doses of UVA do not pose any risk of cancer to pigmented mouse strains.  相似文献   

18.
Contiguous gene syndromes (CGS) are a group of disorders associated with chromosomal rearrangements of which the phenotype is thought to result from altered copy numbers of physically linked dosage-sensitive genes. Smith-Magenis syndrome (SMS) is a CGS associated with a deletion within band p11.2 of chromosome 17. Recently, patients harboring the predicted reciprocal duplication product [dup(17)(p11.2p11.2)] have been described as having a relatively mild phenotype. By chromosomal engineering, we created rearranged chromosomes carrying the deletion [Df(11)17] or duplication [Dp(11)17] of the syntenic region on mouse chromosome 11 that spans the genomic interval commonly deleted in SMS patients. Df(11)17/+ mice exhibit craniofacial abnormalities, seizures, marked obesity, and male-specific reduced fertility. Dp(11)17/+ animals are underweight and do not have seizures, craniofacial abnormalities, or reduced fertility. Examination of Df(11)17/Dp(11)17 animals suggests that most of the observed phenotypes result from gene dosage effects. Our murine models represent a powerful tool to analyze the consequences of gene dosage imbalance in this genomic interval and to investigate the molecular genetic bases of both SMS and dup(17)(p11.2p11.2).  相似文献   

19.
Danazol (17alpha-pregna-2,4-dien-20-yno [2,3-d]-isoxazol-17beta-ol), is a synthetic derivative of ethisterone, structurally related to stanozolol. For this reason its use as doping agent has been investigated. Danazol (Runch) (200 mg) were orally administered to two healthy male volunteers. Urine samples were collected up to 1-week post-dose. Four new metabolites have been identified in addition to the five previously reported. We propose the monitorization of 6beta-hydroxy-2-hydroxymethyl-1,2-dehydroethisterone and 6beta,16epsilon-dihydroxy-2epsilon-hydroxymethyl-ethisterone by free fraction analysis. In a same way, we proposed to detect the principal isomer of a mono-hydroxylated metabolite of 6beta-hydroxy-2epsilon-hydroxymethylethisterone in the conjugated fraction. We conclude that new metabolites can be included for the detection of danazol abuse since the main metabolite ethisterone is excreted relatively fast in urine.  相似文献   

20.
Aspirin induces platelet receptor shedding via ADAM17 (TACE)   总被引:3,自引:0,他引:3  
Aspirin is effective in the therapy of cardiovascular diseases, because it causes acetylation of cyclooxygenase 1 (COX-1) leading to irreversible inhibition of platelets. Additional mechanisms can be suspected, because patients treated with other platelet COX inhibitors such as indomethacin do not display an increased bleeding tendency as observed for aspirin-treated patients. Recently, aspirin and other anti-inflammatory drugs were shown to induce shedding of L-selectin in neutrophils in a metalloproteinase-dependent manner. Therefore, we investigated the effects of aspirin on the von Willebrand Factor receptor complex glycoprotein (GP) Ib-V-IX, whose lack or dysfunction causes bleeding in patients. As quantified by fluorescence-activated cell sorting analysis in whole blood, aspirin, but not its metabolite salicylic acid, induced dose-dependent shedding of human and murine GPIbalpha and GPV from the platelet surface, whereas other glycoproteins remained unaffected by this treatment. Biotinylated fragments of GPV were detected by immunoprecipitation in the supernatant of washed mouse platelets, and the expression level of GPIbalpha was decreased in these platelets as measured by Western blot analysis. Although shedding occurred normally in COX-1-deficient murine platelets, shedding was completely blocked by a broad-range metalloproteinase inhibitor and, more importantly, in mouse platelets expressing an inactive form of ADAM17. Shed fragments of GPIbalpha and GPV were elevated in the plasma of aspirin-injected mice compared with animals injected with control buffer. These data demonstrate that aspirin at high concentrations induces shedding of GPIbalpha and GPV by an ADAM17-dependent mechanism and that this process can occur in vivo.  相似文献   

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