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1.
The purpose of this study was to ascertain whether anabolic steroids act synergistically with functional overload in terms of increasing muscle weight and subcellular protein content of normal overloaded and suspended overloaded rodent plantaris muscle. Female rats were randomly assigned to six groups (7 rats/group) for 6 wk: 1) normal control (NC), 2) overload (OV), 3) overload steroid (OV-S), 4) normal suspended (N-SUS), 5) overload suspended (OV-SUS), and 6) overload suspended steroid (OV-SUS-S). Rats receiving anabolic steroid were administered 0.3 mg nandrolone decanoate (Deca-Durabolin) per day. Relative to control values, overload induced 1) sparing of muscle weight of the OV-SUS group as well as larger absolute and normalized (mg muscle/g body wt) muscle weight of the OV group (P less than 0.05), 2) greater protein content (mg/muscle, P less than 0.05), and 3) an increased relative expression of slow myosin in both the OV and OV-SUS groups (P less than 0.05). Although anabolic steroid treatment of overload animals (OV-S) did not alter further the pattern of response of any parameter analyzed for the OV group, it did induce larger absolute and normalized muscle weight (P less than 0.05) as well as a greater protein content (mg/muscle, P less than 0.05) of the OV-SUS-S group compared with control values. However, anabolic steroid treatment did not alter the pattern of isomyosin expression observed in the overload (OV-S vs. OV) or overload suspended (OV-SUS-S vs. OV-SUS) groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
The efficacy of anabolic steroid treatment [0.3 or 0.9 mg nandrolone decanoate (Deca-Durabolin) per day] was examined in the context of sparing rodent fast-twitch plantaris and slow-twitch soleus muscle weight, sparing subcellular protein, and altering isomyosin expression in response to hindlimb suspension. Female rats were assigned to four groups (7 rats/group for 6 wk): 1) normal control (NC), 2) normal steroid (NS), 3) normal suspension (N-SUS), and 4) suspension steroid (SUS-S). Compared with control values for the plantaris and soleus muscles, suspension induced 1) smaller body and muscle weight (P less than 0.05), 2) losses in myofibril content (mg/muscle, P less than 0.05), and 3) shifts in the relative expression (expressed as %of total isomyosin) of isomyosins which favored lesser slow myosin and greater fast myosin isotypes (P less than 0.05). Steroid treatment of suspended animals (SUS-S vs. N-SUS) partially spared body and muscle weight (P less than 0.05) and spared plantaris but not soleus myofibril content (mg/muscle, P less than 0.05). However, steroid treatment did not modify the isomyosin pattern induced by suspension. In normal rats (NS vs. NC), steroid treatment enhanced body and plantaris muscle weight but not soleus weight (P less than 0.05) and did not alter isomyosin expression in either muscle type. Collectively these data suggest that in young female rats anabolic steroids 1) enhance the body weight and the weight of a fast-twitch ankle extensor in normal rats, 2) ameliorate the loss in body weight, fast-twitch muscle weight and protein content and slow-twitch muscle weight associated with hindlimb suspension.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
Functionally overloading rat soleus muscle by synergist ablation induces a rapid increase in mass. Muscle remodeling during the first week of overload is critical for the overload-induced growth. Anabolic steroid modulation of this overload-induced remodeling response is not well understood. The purpose of this study was to determine whether pretreatment with nandrolone decanoate, a clinically administered anabolic steroid, alters muscle morphology and gene expression related to muscle growth during the initiation of functional overload in the rat soleus muscle. Adult (5 mo) male Fisher 344 x Brown Norway rats were randomly assigned to control (Sham), 3-day functional overload (OV), nandrolone decanoate administration (ND), or 3-day functional overload with nandrolone decanoate administration (OV+ND) treatment groups. Morphologically, OV increased the percentage of small (361%) and large (150%) fibers and expanded the ECM 50%. ND administration decreased the 3-day OV induction of small fibers 51% and nuclei associated with the ECM 20%. ND administration also attenuated the induction of cell cycle regulator p21 (64%) and myogenin (37%) mRNAs after 3 days of overload. These data demonstrate that nandrolone decanoate pretreatment can alter morphological and cell cycle regulator expression related to muscle growth at the onset of functional overload.  相似文献   

4.
The ability of an anabolic steroid, nandrolone decanoate, to increase committed topoietic stem cell (CFU-gm, CFU-e, and BFU-e) colony formation after sublethal irradiation was evaluated. Immediately after receiving whole body irradiation and on the next two days, each mouse was injected intraperitoneally with nandrolone decanoate (1.25 mg) in propylene glycol. Irradiated control mice received only propylene glycol. Compared to controls, drug-treated mice showed marked peripheral blood leukocytosis and more stable packed red cell volume. Drug-treated mice also demonstrated increased erythropoiesis, as CFU-e/BFU-e concentrations from both marrow (9% to 581%) and spleen (15% to 797%) were elevated. Granulopoiesis was increased similarly, as CFU-gm concentrations from marrow (38% to 685%) and spleen (9% to 373%) were elevated. These results demonstrate that nandrolone decanoate enhances hematopoietic stem cell recovery after sublethal whole body irradiation. This suggests that following hematopoietic suppression, nandrolone decanoate may stimulate the recovery of hematopoiesis at the stem cell level and in peripheral blood.  相似文献   

5.
Anabolic steroids are widely used to increase skeletal muscle (SM) mass and improve physical performance. Some dietary supplements also include potent steroid precursors or active steroid analogs such as nandrolone. Our previous study reported the anabolic steroid effects on SM in a castrated guinea pig model with SM measured using a highly quantitative magnetic resonance imaging (MRI) protocol. The aim of the current study was to apply this animal model and in vivo MRI protocol to evaluate the growth effects of four widely used over-the-counter testosterone and nandrolone precursors: 4-androstene-3 17-dione (androstenedione), 4-androstene-3β 17β-diol (4-androsdiol), 19-nor-4-androstene-3β-17β-diol (bolandiol) and 19-nor-4-androstene-3 17-dione (19-norandrostenedione). The results showed that providing precursor to castrated male guinea pigs led to plasma steroid levels sufficient to maintain normal SM growth. The anabolic growth effects of these specific precursors on individual and total muscle volumes, sexual organs, and total adipose tissue over a 10-week treatment period, in comparison with those in the respective positive control testosterone and nandrolone groups, were documented quantitatively by MRI.  相似文献   

6.
The study had been conducted to evaluate the effects of nandrolone decanoate (abused repeated doses) on female rat’s ovary and uterus during administration and withdrawal. The study included 18 rats that were divided into control group (n = 6) and treated group (n = 12). The treated group was injected intramuscular (IM) with nandrolone decanoate (7 mg/kg body weight) for three consecutive days, for two weeks. The study stated that nandrolone decanoate increases the weights of body, ovary, and uterus. Moreover, it has a tendency of bringing upon modifications in the biochemical, histopathological, and morphological makeup of the female reproductive aspects. In conclusion, nandrolone decanoate has been identified as deleterious element for the female rats, and it is suggested that keen observations must be made on the human abusers to control and manage the possible pathologies.  相似文献   

7.
To examine whether concomitant anabolic steroid treatment combined with training might enhance previously observed training effects (A. Bisschop, G. Gayan-Ramirez, H. Rollier, R. Gosselink, R. Dom, V. de Bock, and M. Decramer. Am. J. Respir. Crit. Care Med. 155: 1583-1589, 1997) and whether insulin-like growth factor I (IGF-I) was involved in these changes, male and female rats were submitted to inspiratory muscle training (IMT) for 8 wk (30 min/day, 5 times/wk) and were compared with untrained controls. During the last 5 wk of training, trained rats were divided to receive weekly either low-dose (LD; 1.5 mg/kg) or high-dose (HD; 7.5 mg/kg) nandrolone decanoate or saline for the IMT and control rats. In both sexes, diaphragm muscle mass and contractile properties were unchanged with treatment. In males, HD resulted in decreased diaphragm type I cross-sectional area (-15%; P < 0.05, HD vs. IMT), whereas no changes were observed in females. Finally, an increase in IGF-I mRNA levels was present in HD male (+73%; P < 0.05, HD vs. IMT) and female treated rats [LD (+58%) and HD (+96%) vs. IMT; P < 0.001]. We conclude that administration of nandrolone decanoate did not enhance the previously observed training effects in rat diaphragm, although it increased the IGF-I mRNA expression levels.  相似文献   

8.
The aim of this investigation was to study the effect of the doping steroid nandrolone on metamizol and morphine-induced analgesia and tolerance/dependence in rats. Nandrolone per se did not change the basal nociceptive thresholds in both sexes. It diminished the analgesic effect of metamizol in females, revealed by tail flick test, and males, revealed by paw pressure and hot plate tests. In general, the action of nandrolone was to decrease the morphine-induced analgesia in female and male rats. This was strongly manifested by paw pressure and tail flick tests in male, and tail flick tests in female animals. Nandrolone slowed the development of opioid tolerance/dependence. It aggravated the withdrawal syndrome in the females and invigorated aggression in the males. The data provide evidence that anabolic steroid nandrolone might decrease the analgesic action of metamizol or morphine. The doping steroid could modulate opioid tolerance/dependence and the aggressive behavior in a gender dependent manner. The action of nandrolone is most likely due to profound long-term effects on the central nervous system and might be a gateway to addiction of other drugs of abuse.  相似文献   

9.
Skeletal muscle is a target of anabolic steroid action; however, anabolic steroid's affect on aged skeletal muscle is not well understood. The effect of 4 wk of nandrolone decanoate (ND) administration on hindlimb muscles of 5- and 25-mo-old Fischer 344/Brown Norway rats was examined. ND (6 mg/kg body wt) was injected every 7th day for 4 wk. Controls received an oil injection. ND significantly reduced 25-mo-old rat perirenal fat pad mass by 30%. Soleus (Sol) and plantaris (Plan) muscle-to-body weight ratios were reduced in 25-mo-old rats. ND did not affect Sol or Plan muscle-to-body weight ratios at either age. Sol DNA concentration was reduced by 25% in 25-mo-old rats, and ND increased it to 12% greater than 5-mo-old rats. ND did not affect Plan DNA content. Sol androgen receptor (AR) protein in 25-mo-old rats was reduced to 35% of 5-mo-old values. ND increased AR protein by 900% in 25-mo-old rat Sol. Plan AR concentration was not affected by aging but was induced by ND in both age groups. Aging or ND treatment did not affect glucocorticoid receptor levels in either muscle. These data demonstrate that fast- and slow-twitch rat hindlimb muscles differ in their response to aging and ND therapy.  相似文献   

10.
The purpose of this study was the evaluation of changes induced by training (swimming 1 h/day, 5 days/week, 6 weeks) and an anabolic hormone (nandrolone decanoate, intramuscular injections of 15 mg.kg-1 per week) on fiber size, capillarization and mitochondrial fraction of murine soleus muscle. The animals (n = 32) were divided into 4 groups: a control group (C), that received the arachis oil carrier; a steroid group (S), that received the hormone; a training group (T), and a group that was submitted to training and to the administration of hormone (S + T). The soleus muscle was selected for quantitative light- and electron-microscopic evaluation. The muscle fiber size was increased in group T and decreased in groups S and S + T. The axial length of capillaries per unit volume of muscle decreased significantly in groups S and T. The number of capillaries per number of fibers showed a significant decrease in groups S and S + T and an increase in group T. The mitochondrial content decreased in group S, which suggested that anabolic steroids can be harmful for these organelles. This hypothesis was confirmed by histological evaluation at the electron-microscopic level. Many swollen and disrupted mitochondria were found in groups S and S + T. The results suggest that administration of nandrolone decanoate may have some deleterious effects on the muscle respiratory system (capillaries and mitochondria).  相似文献   

11.
Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.  相似文献   

12.
The action of trenbolone acetate, a synthetic anabolic steroid, on ovarian function was investigated in the guinea pig. Certain comparisons were made with testosterone, the naturally occurring androgen, administered as the phenylpropionate ester. Two milligrams trenbolone acetate per kg given subcutaneously on alternate days for 20 days blocked oestrous cyclicity and ovulation in 9 of 10 animals. A similar effect was shown by 2.2 mg of testosterone phenylpropionate. Treatment of trenbolone acetate-treated animals with exogenous gonadotrophins suggested that the production of follicle-stimulating hormone had been suppressed. Signs of abnormality were seen in the livers of animals receiving 2 mg trenbolone acetate and 2.2 mg testosterone phenylpropionate.  相似文献   

13.
Bone tissue has been shown to contain numerous cell-to-cell signaling peptides called growth factors. These growth factors are thought to have important regulating effects for bone remodeling, due to their potent effects on bone cell metabolism. Our investigation was intended to assess the effect of nandrolone decanoate and calcitonin treatment on biochemical markers of bone formation (bone alkaline phosphatase - osteocalcin) and insulin-like growth factor-I in rats. We studied 48 adult male rats. The animals were divided into four groups. Group (A) served as control. Animals in Group (B) were injected with 4 mg/kg/day nandrolone decanoate. Animals in Group (C) were injected with 400mU/rat/day calcitonin and Group (D) received combined therapy for seven days. Nandrolone decanoate and calcitonin have a mild but significant effect on insulin-like growth factor-I without affecting osteocalcin levels, while calcitonin alone decreases the BALP levels. The coadministration of two agents caused notable elevation on insulin-like growth factor-I, followed by a significant increase of osteocalcin and bone alkaline phosphatase.  相似文献   

14.
Growth enhancement induced by prolonged L-dopa administration in rats   总被引:1,自引:0,他引:1  
To follow growth of rats, in which growth hormone secretion has been chronically stimulated, L-Dopa (5 mg/kg) was injected subcutaneously twice daily for 70 days to growing rats. A control group, matched for sex and sibship, pair fed with the treatment group was given saline injections. At 10-day intervals, the rats were weighed and measured. At 90 days of age the rats were ether anesthesized, bled for growth hormone determination, and internal viscera weighed. Weight gain and length in the L-Dopa-treated group was found to be significantly greater. A mean weight gain of 6% and 12% in the male and female rats, respectively, and a mean length gain of 5% in both male and female rats was observed at 90 days of age. The thymus, thyroid, adrenals, uterus, and gonads all tended to be heavier in the L-Dopa-treated group. Significantly heavier kidneys were found in the L-Dopa group. Serum growth hormone was found to be 8.44 +/- 1.4(SE) ng/ml in the L-Dopa group and 4.6 +/- 0.9 ng/ml in the control group. It is concluded that the continuous administration of L-Dopa produces an increase of circulating serum growth hormone levels, and this in turn enhances growth.  相似文献   

15.
Hallberg M  Kindlundh AM  Nyberg F 《Peptides》2005,26(7):1228-1234
Adult male Sprague-Dawley rats were treated with the anabolic androgenic steroid nandrolone decanoate (15 mg/kg day) or oil vehicle (sterile arachidis oleum) during 14 days. The effect on the densities of the neurokinin NK1 receptor in brain was examined with autoradiography. An overall tendency of attenuation of NK1 receptor density was observed after completed treatment with nandrolone decanoate. The density of the NK1 receptor was found to be significantly lower compared to control animals in the nucleus accumbens core (37% density reduction), in dentate gyrus (26%), in basolateral amygdaloid nucleus (23%), in ventromedial hypothalamic nucleus (36%), in dorsomedial hypothalamic nucleus (43%) and finally in the periaqueductal gray (PAG) (24%). In the cortex region, no structures exhibited any significant reduction of NK1 receptor density. This result provides additional support to the hypothesis that substance P and the NK1 receptor may be involved as important components that participate in mediating physiological responses including the adverse behaviors often associated with chronically administrated anabolic androgenic steroids in human.  相似文献   

16.
Growth hormone (GH) and anabolic androgenic steroids (AAS) are commonly used in sports communities. Several studies have suggested an association between GH and AAS. We have investigated the impact of GH in rats treated with nandrolone decanoate (ND). Male Wistar rats received ND (15 mg/kg) every third day during three weeks and were subsequently treated with recombinant human GH (1.0 IU/kg) for ten consecutive days. Plasma samples were collected and peripheral organs (i.e. heart, liver, testis and thymus) were dissected and weighed. Concentration of thirteen endogenous steroids was measured in the rat plasma samples using high specificity LC–MS/MS methods. Seven steroids were detected and quantified, and concentrations of estrone, testosterone, and androstenedione were significantly different among the groups, while concentrations of pregnenolone, DHEA, 17-hydroxyprogesterone and corticosterone were not altered. Administration of rhGH alone altered the plasma steroid distribution, and the results demonstrated significantly increased concentrations of plasma estrone as well as decreased concentrations of testosterone and androstenedione in the ND-treated rats. Administration of rhGH to ND-pretreated rats did not reverse the alteration of the steroid distribution induced by ND. Administration of ND decreased the weight of the thymus, and addition of rhGH did not reverse this reduction. However, rhGH administration induced an enlargement of thymus. Taken together, the plasma steroid profile differed in the four groups, i.e. control, AAS, rhGH and the combination of AAS and rhGH treatment.  相似文献   

17.
The effect of feeding isocaloric test diets containing 35, 45 and 55% protein, with and without inclusion of the anabolic steroid hormone, ethylestrenol, was studied in rainbow trout, Salmo gairdneri , in relation to blood chemistry. The control (no hormone) and experimental diets (hormone-supplemented), were fed for a total of 60 days, after which time all groups of fish were fed an identical commercial diet with no hormone for a further 30 days (withdrawal period). After 60 days, the body weights offish fed the 35 and 45% experimental diets were significantly greater than their respective controls, and after hormone withdrawal, increased growth was still apparent in the 35% experimental group.
No significant changes in serum amino acid nitrogen (AAN), protein, or glucose in relation to the dietary protein level, or inclusion of steroid, were observed after 30 days. Serum creatinine, however, increased with an increase in dietary protein, and was significantly higher in the 35% experimental group than the respective control. After 60 days, the most significant observation was the marked increase in serum glucose with an increase in dietary protein, but respective control and experimental values were not significantly different at this time. Following a 30-day withdrawal period, serum AAN in the 55% experimental group was significantly higher than the control, whereas serum protein, creatinine, and glucose stabilized to similar concentrations in all groups. Over the 90-day period of feeding, in both control and experimental groups, serum AAN and protein tended to increase, serum creatinine and glucose to decrease, whilst haematocrit remained constant. It is concluded that addition of ethylestrenol to trout diets has apparently little effect on serum metabolite concentrations and haematocrit, the most significant variations being related more to diet composition and duration of study.  相似文献   

18.
Neonatal rats exposed prenatally to phenytoin (PHT) have been reported to have craniofacial abnormalities and growth retardation [Lorente et al.: Teratology 24:169-180, 1981]. This study reports on the persistence of these effects in the adult rat. Pregnant Sprague-Dawley rats were intubated on gestational days 9, 11, and 13 with 1,000 mg/kg PHT suspended in 1% carboxymethylcellulose (CMC). Six male and six female exposed offspring (PHT) and an equal number of control animals (CMC) were weighed through postnatal day 135, at which point they were killed and the skeletons were prepared for analysis. The PHT-exposed animals had reduced weights at all time points with the males more severely affected. A normal adolescent growth spurt was not observed in the exposed group. Absent or rudimentary lacrimal bones and nasolacrimal canals were note in all PHT-exposed rats. This contributed to the recessed positioning of the eyes that was grossly apparent. In addition, shorter and broader frontal bones in the PHT animals led to the appearance of hypertelorism. Ratios of craniofacial dimensions obtained by direct measurement of the skulls showed that the PHT offspring were significantly different in proportion from their control counterparts. The PHT skulls were smaller for body size with reduced facial height and broader midfacial regions. A unique craniofacial pattern was observed in the experimental offspring. Normal sexual dimorphism in craniofacial pattern was not expressed in the PHT group. These studies suggest that prenatal phenytoin exposure in the rat may interfere with the full expression of normal dimorphism based on gender and confirms the toxic effect of this drug on postnatal growth, adult body proportion, and craniofacial geometry.  相似文献   

19.
The haemodynamic effects of 6 weeks nandrolone decanoate treatment (total dose 30 mg.kg-1) (SG I, n = 12) and their reversibility were studied in anaesthetised, open-chest male rats exposed to 5 min isoproterenol (2.5 micrograms.kg-1) and CaCl2 (25.0 mg.kg-1) loads. In SG I, the heart weight and its ratio to body weight were greater than in the untreated rats (CG I, n = 13) (p less than 0.05 and p less than 0.01 respectively). The initial heart rate and the inotropic and chronotropic responses to isoproterenol were lower in SG I than in CG I (p less than 0.05 in all cases). Peripheral resistance decreased during both infusions in SG I but remained unaltered in CG I (p less than 0.05). 6 weeks after finishing anabolic steroid treatment (SG II, n = 11), in the CaCl2-test the ejection fraction (p less than 0.05) and stroke index were smaller than in control rats of the same age (CG II, n = 12). Mean aortic pressure was lower in SG II than in CG II. In the CaCl2-test peripheral resistance was initially higher, but decreased during the infusion in SG II while it increased in CG II (p less than 0.05 in both cases). In conclusion, anabolic steroid treatment reversibly reduces the left ventricular response to isoproterenol. It decreases peripheral vascular tone during inotropic loads. Six weeks after the cessation of treatment, the pumping efficiency of the heart is reduced.  相似文献   

20.
Renato A. Martins 《Steroids》2010,75(12):952-955
The aim of the present study was to evaluate DNA damage (micronucleus) and cellular death (pyknosis, karyolysis and karyorrhexis) in exfoliated buccal mucosa cells from anabolic steroid users after 2 months of exposure. Two experimental groups consisting of 15 adult males who practise weight lifting and are anabolic steroid users or 15 adult males who practise weight lifting, but are non-anabolic steroid users, were recruited. In addition, 20 sedentary males, who do not practise any physical activity regularly, were matched by age with experimental groups. No significant statistical differences (p > 0.05) were noticed in individuals who practise physical activity only. On the other hand, an increase of micronucleated cells (MNCs) in anabolic steroid (decadurabulin and Winstrol) users was observed. Regarding cytotoxic parameters, the same observation has occurred, that is, significant statistical differences (p < 0.05) were noticed in the group exposed to anabolic steroids when compared with other controls, as depicted by high frequencies of pyknosis, karyolysis and karyorrhexis. Taken together, our results suggest that genomic instability and cytotoxicity are induced by anabolic steroid administration in oral mucosa cells as assessed by the micronucleus test.  相似文献   

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