Nandrolone Decanoate Administration Research Articles

Enzymatic conversion of dynorphin A in the rat brain is affected by administration of nandrolone decanoate

The misuse of anabolic androgenic steroids (AAS) seems to produce profound effects on the central nervous system, leading to aggressive behavior and increased sensitivity to other drugs of abuse. The present study addresses the effect on the enzymatic transformation, here called dynorphin converting enzyme-like activity. The formation of the mu/delta opioid peptide receptor-preferring Leu-enkephalin-Arg 6 from the kappa opioid peptide receptor-preferring dynorphin A was measured in rats treated with nandrolone decanoate. Significant variations in enzymatic transformation were observed in several brain regions. An altered receptor activation profile in these regions may be one contributory factor behind AAS-induced personality changes.

Altered extracellular levels of DOPAC and HVA in the rat nucleus accumbens shell in response to sub-chronic nandrolone administration and a subsequent amphetamine challenge

Associated with acts of violence and polydrug use, abuse of anabolic androgenic steroids (AAS) is an increasing problem in society. The aim of the present study was to elucidate whether sub-chronic treatment with the AAS nandrolone decanoate affects dopamine release and dopamine metabolism in the rat nucleus accumbens shell, before and after an amphetamine challenge. Male Sprague–Dawley rats received daily i.m. injections of nandrolone decanoate (15 mg/kg) or vehicle for 14 days. On day 15, the animals were anaesthetized and a microdialysis probe was implanted into the nucleus accumbens shell. Extracellular fluid was collected 1 h before and 3 h after a single amphetamine injection (5 mg/kg). The samples were then analyzed regarding the content of dopamine, and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), using HPLC with electrochemical detection. Two weeks of nandrolone decanoate administration caused a significant decrease of the basal DOPAC and HVA levels, which remained low during the first hour following the amphetamine challenge. Dopamine levels did not differ significantly between groups, neither after the nandrolone pre-treatment nor the amphetamine challenge. In conclusion, these novel findings indicate that AAS alter the metabolism of dopamine in a brain region involved in the development of drug dependence.

Modulation of overload-induced inflammation by aging and anabolic steroid administration

Aging can alter the skeletal muscle growth response induced by overload. The initiation of overload induces muscle extracellular matrix expansion, increased cellularity, and inflammatory gene expression, which are all related to processes important for myofiber growth. These remodeling processes are also biological targets of testosterone. It is not certain how aging affects the inflammatory response to functional overload and whether anabolic steroid administration can alter this response. The effect of anabolic steroid administration on inflammatory processes during functional overload is not known. The purpose of this study was to determine if age altered the skeletal muscle inflammatory response at the onset of functional overload and whether anabolic steroid administration would modulate this response in young or older animals. Five-month and 25 month F344 × BRN rats were given nandrolone decanoate (ND) (6 mg/kg bw/wk) or sham injections for 3 weeks, and then the soleus muscle was overloaded (OV) for 3 days by synergist ablation. ND alone induced a 230% increase in ED1 + cells in 5 month muscle. Three days of OV had no effect on ED1 + cell number at either age. OV combined with ND induced a 90% increase in ED2 + cells in 5 month muscle, while there was no effect of either treatment alone at this age. In 25 month muscle, OV induced a 40% increase in ED2 + cells. Regardless of age, OV induced muscle TNF-α mRNA expression (300%) and IL-6 mRNA expression (900%). ND attenuated OV-induced IL-6 mRNA but not TNF-α expression in both age groups. The overload induction of IL-1β mRNA was 3-fold greater in 25 month muscle (1400%), compared to 5 month muscle (400%). ND administration ablated the overload IL-1β mRNA induction in 25 month muscle. Anabolic steroid administration can suppress inflammatory cytokine gene expression at the onset of overload and this effect is age dependent.

A administração de nandrolona não promove hipertrofia do músculo sóleo em ratos

Anabolic androgenic steroids (AAS) are compounds formed from testosterone or one of its derivatives, which are largely used by amateur e professional athletes to improve the athletic performance. However, the scientific information about the relation between the use of AAS and muscle hypertrophy is controversial. The aim of this study was to evaluate the effects of testosterone and physical training on muscle hypertrophy. Male Wistar rats received i.m. injections of Deca-Durabolin or vehicle during 6 weeks. Trained rats were submitted to a resistance physical training, by jumping up and down in water carrying an overload. Sedentary and trained animals were anesthetized and sacrificed. Soleus muscle was removed for the quantification of total protein and DNA concentration. In the end of the treatment, body weight of trained animals treated with vehicle or AAS was lower than the body weight of respective sedentary. Total protein concentration and the ratio muscle weight/body weight of all experimental groups were not altered. Trained group treated with AAS presented lower DNA concentration than trained group treated with vehicle. The administration of nandrolone decanoate did not promote hypertrophy on soleus muscle, not even when the use of AAS was associated to resistance physical training.

Mitochondrial function in diaphragm of emphysematous hamsters after treatment with nandrolone

Respiratory failure in patients with COPD may be caused by insufficient force production or insufficient endurance capacity of the respiratory muscles. Anabolic steroids may improve respiratory muscle function in COPD. The effect of anabolic steroids on mitochondrial function in the diaphragm in emphysema is unknown. In an emphysematous male hamster model, we investigated whether administration of the anabolic steroid nandrolone decanoate (ND) altered the activity of mitochondrial respiratory chain complexes in the diaphragm. The bodyweight of hamsters treated with ND was decreased after treatment compared with initial values, and serum testosterone levels were significantly lower in hamsters treated with ND than in control hamsters. No difference in the activity of mitochondrial respiratory chain complexes in the diaphragm between normal and emphysematous hamsters was observed. Treatment with ND did not change the activity of mitochondrial respiratory chain complexes in the diaphragm of both normal and emphysematous hamsters. In emphysematous hamsters, administration of ND decreased the activity of succinate:cytochrome c oxidoreductase compared with ND treatment in normal hamsters. We conclude that anabolic steroids have negative effects on the activity of succinate:cytochrome c oxidoreductase and anabolic status in this emphysematous hamster model.

Chronic Administration of Nandrolone Decanoate Does Not Increase the Plasma Homocysteine Level of Male Rats

Androgenic-anabolic steroids are used widely by many athletes in order to increase muscle mass and strength. Since plasma total homocysteine, an independent risk factor of vascular diseases, is higher in men than in women, it has been proposed that androgenic hormones could increase the plasma total homocysteine level and it might play some role in sudden death when used at supraphysiological doses. To study the association between the use of androgenic-anabolic steroids and plasma homocysteine level, nandrolone decanoate was administered in 3 and 10 mg/kg doses to male rats by intramuscular weekly injections. Control animals received the solvent of nandrolone decanoate. After 14 weeks, plasma total homocysteine level was measured. In order to make sure about the adequacy of doses and bioavailability of drug, testes parameters were also considered. While all testes parameters were suppressed significantly, no association between androgenic-anabolic steroids use and total homocysteine level was found. It is concluded that chronic administration of nandrolone decanoate does not have any significant effect on plasma total homocysteine of male rats. Thus, factors other than plasma total homocysteine level may contribute to increased cardiovascular events after chronic abuse of androgenic-anabolic steroids.

Administration of the anabolic androgenic steroid nandrolone decanoate affects substance P endopeptidase-like activity in the rat brain

The effect of the anabolic androgenic steroid, nandrolone decanoate, on substance P endopeptidase-like activity was examined in adult male Sprague–Dawley rats. Nandrolone decanoate (15 mg/kg day) or oil vehicle (sterile arachidis oleum) were administered by intramuscular injections during 14 days. Substance P endopeptidase, a predominantly cytosolic enzyme, generates the bioactive N-terminal fragment substance P 1–7 from the enzyme substrate substance P. Nandrolone decanoate significantly reduced the substance P endopeptidase-like activity compared to control animals in hypothalamus (43% reduction), caudate putamen (44%), substantia nigra (32%) and the ventral tegmental area (27%). It was previously reported that both hypothalamus and caudate putamen contained significantly higher levels of substance P after nandrolone administration. The higher concentration of substance P in these regions could to an extent be attributed to the reduction in substance P endopeptidase-like activity. This result elucidates the important role of peptidase activity in the regulation of the substance P transmitter system. The present study provides additional support for the hypothesis that alterations in the substance P system in certain brain areas may contribute to some of the personality changes reported in connection with AAS abuse.

Nandrolone decanoate modulates cell cycle regulation in functionally overloaded rat soleus muscle

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.

Anabolic androgenic steroid affects social aggression and fear-related behaviors in male pair-housed rats

This study examines the effect of chronic administration of the anabolic androgenic steroid nandrolone decanoate (ND) on dominant and subordinate male rats in a pair-housed condition. Pair-housed rats were assessed for dominance status based on their behavior and alterations in body weights. Throughout the study the rats were allowed limited social interactions on a daily basis. At all other times, a Plexiglas divider kept the rats separated, allowing olfactory and visual contact between the cage mates while preventing significant physical contact. One week into the study all subjects were subcutaneously implanted with a pellet that continuously infused either ND (15 mg/kg/day) or placebo for 21 days. Following the pellet implant, behavioral tests including reassessment for dominance status, and a conditioned fear test were conducted over a period of approximately 2 months to investigate possible long-term changes. The main finding is that during the allowed social interactions, the dominant ND-pretreated rats spent more time on highly aggressive behaviors than the dominant placebo-treated rats. In addition, the probability for highly aggressive behaviors was maintained for the ND-treated rats throughout the study, whereas it was decreased for the placebo-treated rats. The ND-treated subordinate rats showed less fear in a potential threatening situation compared to placebo-treated controls. These findings support the relatively long-term behavioral changes that have been seen in humans after abuse of ND and other anabolic androgenic steroid compounds.

The impact of chronic nandrolone decanoate administration on the NK1 receptor density in rat brain as determined by autoradiography

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.

Effects of androgenic-anabolic steroids on apolipoproteins and lipoprotein (a)

Objectives: To investigate the effects of two different regimens of androgenic-anabolic steroid (AAS) administration on serum lipid and lipoproteins, and recovery of these variables after drug cessation, as indicators of...

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

Increased dopamine transporter density in the male rat brain following chronic nandrolone decanoate administration

Adolescent males currently employ anabolic-androgenic steroids (AAS) to become intoxicated, besides the traditional desires of an improved physical appearance and enhanced sports performance. Several studies indicate that AAS affect the brain reward system. Recently chronic administration with nandrolone decanoate to male rats has been shown to increase the dopamine transporter (DAT) density in the striatum visualised in vivo by positron emission tomography. The present study aimed to investigate if the increased DAT density could be confirmed using in vitro autoradiography following a comparable regimen of nandrolone treatment. Specific binding of 50 pM [ 125I] RTI-55 in the presence of 1 μM citalopram was used to label DAT. Two weeks of nandrolone decanoate administration at the supra-therapeutic doses 1, 5 and 15 mg/kg per day increased DAT density in the caudate putamen at all three doses. In conclusion, this study confirms that chronic nandrolone administration increases dopamine transporter density in the CPU and therefore supports the theory that AAS affects the dopamine system in the male rat brain.

Regulation of androgen receptor expression at the onset of functional overload in rat plantaris muscle.

Skeletal muscle androgen receptor (AR) expression at the onset of functional overload (OV) has not been well described. It is also not known if overload and/or anabolic steroid differentially regulate AR expression. The purpose of this study was to examine AR gene expression at the onset of functional OV in rat plantaris muscle with and without nandrolone decanoate (ND) administration. The functional significance of AR protein induction was examined using skeletal alpha-actin promoter activity in transiently transfected CV-1 fibroblast cells. Male Sprague-Dawley rats ( approximately 125 g) were functionally overloaded for 1, 3, 7, or 21 days. A subset of animals was given an ND (6 mg/kg) injection at day 0 and then overloaded for 3 days. Control animals underwent sham surgeries. AR protein concentration increased 106 and 279% after 7 and 21 days of OV, respectively. AR mRNA increased 430% after 7 days of OV. AR protein expression in C2C12 murine myotubes subjected to 1% chronic radial stretch for 18 h was elevated 101% compared with control. ND treatment increased AR protein concentration 1,300% compared with controls, and there was no additional effect when ND and OV were combined. ND with 3 days of OV treatment increased AR mRNA expression 50% compared with control. AR overexpression in transiently transfected CV-1 fibroblast cells increased -424 bp skeletal alpha-actin promoter activity 80 to 1,800% in a dose-dependent fashion. Co-overexpression of either serum response factor (SRF) or active RhoA with AR overexpression induced a synergistic 36- and 28-fold induction of skeletal alpha-actin promoter. Cotransfection of AR, SRF, and active RhoA induced 180-fold increase in skeletal alpha-actin promoter activity. In conclusion, AR protein expression is increased after 7 days of functional OV, and this induction is regulated pretranslationally. AR induction in conjunction with SRF and RhoA signaling may be an important regulator of gene expression during overload-induced muscle growth.

Overload-induced androgen receptor expression in the aged rat hindlimb receiving nandrolone decanoate.

This study's purpose was to examine whether functional overload with nandrolone decanoate (ND) administration increased muscle mass and steroid receptor concentration in aged rat soleus (Sol) and plantaris (Plan) muscle. ND (6 mg/kg body wt) was administered once a week for 4 wk, whereas control rats received sesame seed oil injections. Functional overload of the hindlimb Sol and Plan was induced by synergistic gastrocnemius muscle ablation at the beginning of the fourth week. Adult (5 mo of age) and aged rats (25 mo of age) were randomly assigned to four groups: control, overload, control-ND, and overload-ND. Seven days of functional overload increased adult Sol muscle mass 27%, whereas the aged Sol muscle mass did not change. The aged overloaded Sol muscle receiving ND significantly increased muscle weight by 35% and total muscle protein by 24%. Aged Plan muscle did not increase muscle weight with overload or ND treatment. Androgen receptor protein was induced by ND treatment and functional Ov, and combining the two treatments induced Sol androgen receptor protein concentration above either alone. Sol glucocorticoid receptor protein concentration increased in overload groups of both ages. ND administration can increase aged Sol muscle mass and protein content after 7 days of functional overload, and the cooperative induction of androgen receptor may be important for this response.

Steroid receptor concentration in aged rat hindlimb muscle: effect of anabolic steroid administration.

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.

RAT SKELETAL MUSCLE RHOA EXPRESSION WITH FUNCTIONAL OVERLOAD AND ANABOLIC STEROID ADMINISTRATION.

RhoA exerts signaling involved in the formation of focal adhesion complexes and is a potentially important mediator of muscle gene regulation during overload induced growth. PURPOSE: To determine what effect functional overload with and without nandrolone decanoate (ND) administration had on RhoA expression in rat plantaris muscle. METHODS: Male Sprague Dawley (125g) rats were randomly assigned to Con (n = 9), 3 day (n = 5), or 21 day (n = 5) overload groups. Compensatory overload (OV) was induced by the synergist ablation of the distal 1/3rd of the medial and lateral gastrocnemius muscles of the hindlimb. Animals were randomly assigned to intramuscular injections of Sesame Oil (n = 12) or ND (n = 12, 6mg/kg). At the appropriate time animals were anesthetized and the fast twitch plantaris muscle was excised and frozen for analysis of muscle mass, protein concentration, RNA concentration, and RhoA expression. RESULTS: Muscle mass (mg) significantly increased (p < 0.05) from Con (109 ± 4) with 3 days of OV (143 ± 3) and OV+ND (144 ± 4) administration. Muscle mass also significantly (p < 0.05) increased from Con (257 ± 7) with 21 days of OV (309 ± 3) and OV+ND (333 ± 5) administration. RNA concentration (ug/mg) increased (p < 0.05) from Con (1.77 ± .1) with 3 days of OV (2.64 ± .44) and OV+ND (2.57 ± .12). Similarly with 21 days of OV+ND, RNA concentration increased (1.68 ± .16) from Con (1.19 ± .13). Western Blot analysis revealed an increase (p < 0.05) in RhoA expression at 3 days from Con (1.06 ± .13) with OV (2.15 ± .21), ND (1.76 ± .11) and OV+ND (3.85 ± .62). RhoA expression remained elevated from Con (1.00 ± .34) at 21 days with ND (3.80 ± .35). CONCLUSION: RhoA expression is induced by OV and ND administration alone. However, there is a synergistic effect of OV+ND to increase RhoA expression in rat plantaris muscle. The results of this study suggest that increases in RhoA expression with OV and/or OV+ND mirror increases in mass in the fast twitch plantaris muscle of adult rats. Supported by the South Carolina Space Grant Consortium and American College of Sports Medicine NASA Space Grant.

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

Body Composition and Anthropometry in Bodybuilders:Regional Changes due to Nandrolone Decanoate Administration

The purpose of the present study was to investigate regional changes in body composition and anthropometric variables induced by nandrolone decanoate in bodybuilders. In a randomized, double blind, placebo controlled design 16 subjects received weekly intramuscular injections containing 200 mg nandrolone decanoate (ND) or placebo. Composition of total body and body parts were assessed using dual energy X-ray absorptiometry (DEXA), skinfolds and circumferences. Measurements were performed at baseline, after 8 weeks ND administration period and 6 weeks after drug withdrawal. DEXA revealed that total body mass (from 76.16 ± 2.70 to 78.73 ± 4.07 kg, p < 0.5) and bone-free lean mass (from 59.54 ± 2.36 to 63.06 ± 2.99 kg, p < 0.025) increased significantly during ND administration whereas bone mineral mass remained unchanged. Six weeks after drug cessation bone-free lean mass was still increased compared to baseline levels. During ND administration significant increments of bone-free lean mass of the trunk (+ 2.03 kg) and legs (+ 1.08 kg) could be observed. Percentage fat of the legs decreased during the drug intervention period (- 1.9 %) and remained lowered six weeks after drug withdrawal. No alteration in any variable of the arms was observed. Skinfolds did not change during the entire study period in both groups. After 8 weeks ND administration circumference of the neck was increased (+ 0.9 cm) significantly although all circumferences underwent non-significant gains. In conclusion, the intramuscular administration of nandrolone decanoate (200 mg per week) during eight weeks induced an increase of body weight and bone-free lean body mass in bodybuilders that was mainly situated in the trunk and legs as determined by DEXA. The changes in the trunk were reflected in the circumferences but not the alterations in the legs. Skinfolds were not able to detect changes of fat mass of body parts. DEXA revealed that total fat mass and total percentage fat remained unaffected by drug administration while percentage fat of the legs decreased and remained lowered after drug cessation. These data indicate that changes of the composition of body parts induced by ND are elucidated less accurately by circumferences or skinfolds rather than by DEXA.