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1.
In hamsters, adolescent anabolic-androgenic steroid (AAS) exposure facilitates offensive aggression, in part by altering the development and activity of anterior hypothalamic arginine vasopressin (AH-AVP). This study assessed whether these effects were lasting by examining aggression and AH-AVP during AAS withdrawal. Adolescent hamsters administered AAS were tested as adults for aggression at 1, 4, 11, 18, or 25 days of withdrawal, sacrificed the following day, and examined for AH-AVP afferent innervation using immunohistochemistry. Through Day 12 of withdrawal, aggression and AVP were significantly higher in AAS-treated hamsters than in controls. These differences were no longer observable by Day 19 of withdrawal, at which point the behavior and neurobiology of AAS-treated hamsters reverted to that observed in controls. These data indicate that adolescent AAS exposure has short-term, reversible effects on both aggression and AH-AVP, correlating AH-AVP with the aggressive/nonaggressive behavioral phenotype during AAS withdrawal.  相似文献   

2.
Human studies show that the number of teenagers abusing anabolic androgenic steroids (AAS) is increasing. During adolescence, brain development is altered by androgen exposure, which suggests that AAS may potentially alter central nervous system (CNS) development. The goal of the present study was to determine whether pubertal AAS exposure increased dendritic spine densities on neurons within the medial amygdala and the dorsal hippocampus. Pubertal gonadally intact male rats received the AAS testosterone propionate (5 mg/kg) or vehicle for 5 days/week for 4 weeks. To determine the long-term implications of pubertal AAS use, another set of males received the same AAS treatment and was then withdrawn from AAS exposure for 4 weeks. Results showed that pubertal AAS exposure significantly increased spine densities on neurons in the anterior medial amygdala, posterodorsal medial amygdala, and the cornu ammonis region 1 (CA1) of the hippocampus compared with gonadally intact control males. Spine densities returned to control levels within the anterior medial amygdala and the posterodorsal medial amygdala 4 weeks after withdrawal. However, spine densities remained significantly elevated after AAS withdrawal in the CA1 region of the hippocampus, suggesting that pubertal AAS exposure may have a long-lasting impact on CA1 hippocampal neuroanatomy. Since pubertal AAS exposure increased spine densities and most excitatory synapses in the CNS occur on dendritic spines, AAS may increase neuronal excitation. It is proposed that this increase in excitation may underlie the behavioral responses seen in pubertal AAS-treated male rats.  相似文献   

3.
Adolescent exposure to anabolic androgenic steroids (AAS) alters the development and activity of the glutamate neural system in the latero-anterior hypothalamus (LAH) in hamsters (Mesocricetus auratus); that is, an important neural component of the adolescent AAS-induced aggressive response. In this article, we used retrograde tracing to investigate glutamate-specific alterations in the connections between the LAH and several other nuclei implicated in adolescent AAS-induced aggression. Briefly, hamsters were treated with AAS or sesame-oil control during adolescence and then microinjected with retrograde tracer into the medial amygdala (MeA), lateral septum (LS), or bed nucleus of the stria terminalis (BNST). Brains were then processed for vesicular glutamate transporter 2 (VGLUT2) and examined for AAS-induced changes in the number VGLUT2 cells containing retrograde tracer (VGLUT2/tracer) within the LAH. It is interesting to note that while aggressive AAS-treated hamsters injected retrograde tracer into the MeA showed a significant reduction in the number of VGLUT2/tracer cells in the LAH, aggressive AAS-treated hamsters injected tracer into the BNST showed a significant increase in the number of VGLUT2/tracer cells in the LAH when compared with controls. Last, AAS hamsters injected with tracer into the LS had a comparable number of LAH-VGLUT2/tracer cells to controls. The current results indicate that glutamate likely functions as the major aggression output system from the LAH and that adolescent AAS treatment significantly alters the neural circuitry modulating aggression. Moreover, increases in the number of glutamate projections from the LAH to the BNST in AAS hamsters identify the BNST as an area particularly important for the regulation of AAS-induced aggression.  相似文献   

4.
Repeated high dose (5.0 mg/kg) anabolic-androgenic steroid (AAS) exposure during adolescence stimulates offensive aggression in male Syrian hamsters. These studies examined whether AAS-induced aggression was regulated by the activity of serotonin (5HT) type-1B receptors and correlated with altered 5HT1B expression. AAS-treated hamsters were tested for offensive aggression following the administration of the 5HT1B agonist anpirtoline (0.125-0.5 mg/kg). Anpirtoline dose-dependently reduced select components of the AAS-induced aggressive response, with significant reductions observed at 0.25 mg/kg. Aggressive, AAS-treated hamsters showed significant decreases in the area covered by 5HT1B-containing neuronal puncta and increases in the number of 5HT1B-containing neuronal somata in select brain regions implicated in aggression control. Together, these data support a role for site-specific alterations in 5HT1B signaling and expression in adolescent AAS-induced aggression.  相似文献   

5.
There is increasing abuse of androgenic anabolic steroids (AAS) by non-athletes. AAS abuse has been associated with psychiatric symptoms such as mania, major depression and aggression and the development of dependence. Little is known about the effects of AAS on hypothalamic-pituitary-adrenal axis function or corticotropin releasing factor, which may be involved in mediating some of the psychiatric symptoms associated with AAS abuse. Male Sprague-Dawley rats received one daily intra-muscular injection of the AAS nandrolone decanoate (ND, 15 mg/kg) or vehicle for 3 days. Animals were sacrificed either 1 h or 24 h after the last injection, brain regions dissected and trunk blood collected. Corticotropin releasing factor (CRF), CRF receptor1 (CRF-R1) and proopiomelanocortin (POMC) mRNAs were measured with solution hybridization/RNase protection. Circulating levels of corticosterone and adrenocorticotropin hormone (ACTH) were determined using radioimmunoassays. One hour following the last injection, ND significantly increased circulating levels of both corticosterone and ACTH levels. In the amygdala, CRF mRNA levels were unchanged 1 h after the last injection of ND but were significantly reduced at 24 h. The same was found for hypothalamic POMC. No significant AAS effects were observed on: hypothalamic CRF mRNA; POMC mRNA in the amygdala or CRF R1 mRNA in the anterior pituitary.  相似文献   

6.
目的 探讨改良阿氏评分结合血清C反应蛋白(CRP)检测对儿童急性阑尾炎(acute appendicitis,AAS)的临床应用价值.方法 回顾性分析2015年11月至2016年11月期间我院儿科就诊的78例急性阑尾炎患儿为研究对象,单纯性AAS组32例,化脓性AAS组28例,穿孔性AAS组18例,选取同期体检的正常儿童10例为对照组,采用改良阿氏(Alvarado)评分结合血清CRP检测为受试患儿和正常对照组进行全面评估.结果 手术前单纯性AAS组、化脓性AAS组、穿孔性AAS组CRP参数水平依次上升,且显著高于对照组,组间比较差异有统计学意义(P<0.05);单纯性AAS组、化脓性AAS组、穿孔性AAS组术后CRP参数均较术前明显下降(P<0.05),然而依然高于对照组(P<0.05).与单纯性AAS组、化脓性AAS组比较,穿孔性AAS组患儿手术前Alvarado评分、血清CRP阳性率及二者均阳性的百分比均明显提高(P<0.05);化脓性AAS组的血清CRP阳性率与二者均阳性率明显高于单纯性AAS组(P<0.05).结论 血清CRP检测有助于儿童AAS病情诊断、病理分型以及病情程度,改良Alvarado评分联合CRP对诊断AAS具有良好的互补性,能有效提高AAS术前诊断准确性,对临床科学治疗有指导作用,值得临床推广.  相似文献   

7.
Anabolic-androgenic steroid (AAS) compounds rank among the drugs most widely abused with the goal of improving athletic ability, appearance, or muscle mass. It has been shown that these compounds have adverse effects on human and animal physiology and sperm quality, but quantitative structural changes of the testis have received less attention. The present study was conducted to evaluate the effects of nandrolone decanoate, which is one of the AAS compounds, on testis weight and volume, diameter and length of seminiferous tubules in rats by unbiased stereological methods. Adult rats were divided into three groups. The first comprised control rats; the second and third groups received low and high doses of nandrolone decanoate for 14 weeks. The rats were then left untreated for 14 weeks. After removal of the testis, stereological study of these tissues showed that the mean volume of testis and length of the seminiferous tubules in the animals that received high doses of nandrolone decanoate were reduced approximately 32% (p<0.01) and approximately 31% (p<0.04), respectively, in comparison with the control group. It can be concluded that the high doses of nandrolone decanoate produce structural changes in the rat testis that remain 14 weeks after stopping injection of the drug.  相似文献   

8.
BACKGROUND: Although numerous studies have documented the psychiatric and physiological effects of anabolic-androgenic steroids (AAS) in males, virtually no studies have investigated the effects of illicit AAS use in women. METHODS: We performed psychiatric and medical evaluations of 75 dedicated women athletes, recruited by advertisement primarily from gymnasiums in the Boston, Mass., area. RESULTS: Twenty-five (33%) of the women reported current or past AAS use. Users were more muscular than nonusers and reported use of many other 'ergogenic' (performance-enhancing) drugs in addition to AAS. Some described a frank syndrome of ergogenic polysubstance dependence, often with significant morbidity. Fourteen (56%) of the users reported hypomanic symptoms during AAS use and 10 (40%) reported depressive symptoms during AAS withdrawal, but none met full DSM-IV criteria for a hypomanic or major depressive episode. Nineteen (76%) users reported at least one adverse medical effect associated with AAS use. Perhaps the most interesting findings were several unusual psychiatric syndromes reported by both the AAS users and nonusers. These included rigid dietary practices (which we have termed 'eating disorder, bodybuilder type'), nontraditional gender roles and chronic dissatisfaction and preoccupation with their physiques (a syndrome which we have termed 'muscle dysmorphia'). CONCLUSIONS: Dedicated women athletes exhibit not only AAS abuse, but use of many other ergogenic drugs, sometimes associated with significant morbidity. In addition, these athletes frequently display several psychiatric syndromes which have not previously been well described.  相似文献   

9.
The effects of preconditioning using mild repetitive hypobaric hypoxia (360 Torr for 2 h each of 3 days) have been studied in the learned helplessness model of depression in rats. Male Wistar rats displayed persistent depressive symptoms (depressive-like behaviour in open field, increased anxiety levels in elevated plus maze, ahedonia, elevated plasma glucocorticoids and impaired dexamethasone test) following the exposure to unpredictable and inescapable footshock in the learned helplessness paradigm. Antidepressant treatment (ludiomil, 5 mg/kg i.p.) augmented the development of the depressive state. The hypoxic preconditioning had a clear antidepressive action returning the behavioural and hormonal parameters to the control values and was equally effective in terms of our study as the antidepressant. The findings suggest hypoxic preconditioning as an effective tool for the prophylaxis of post-stress affective pathologies in humans.  相似文献   

10.
Anabolic androgenic steroid (AAS) use increased dramatically among adolescent males. This review focuses on studies using animal models of AAS exposure during adolescence which is a hormonally sensitive developmental period. AAS exposure during this critical period has wide-ranging consequences, including increased dendritic spine density, altered brain serotonin levels and escalated aggression in response to physical provocation. Human data suggest that AAS induces indiscriminate and unprovoked aggression often described as “'roid rage”. However, animal studies indicate that the behavioral impact of AAS is modulated by experiential and social contingencies, a perceived provocation, and the chemical composition of the AAS. The AAS, testosterone increases aggression in juvenile and adult male rats when physically provoked. In contrast, stanzolol, inhibits aggression in both juvenile and adult male rats, even when physically provoked. Nandrolone has minimal effects on aggression, unless preceded by attack training. Exposure to AAS during adolescence may have a host of unintended bio-behavioral consequences. Yet, the perception of harmlessness surrounds AAS use. The perception of harmlessness is promoted by the availability of AAS especially through internet pharmacies. The perception of acceptability is reflected in current cultural ethics that no longer condemn cheating to obtain personal achievement or success. A prevailing conviction is that although AAS are illegal they are not really bad. Reduction of the availability of AAS to adolescents requires ardent legislative and legal intervention. The problem of acceptability can be addressed by educating adolescents about the short-term and long-term effects of AAS on brain and behavior, to increase awareness of the potential consequences of AAS use that apply directly to them.  相似文献   

11.
12.
In gonadally intact male rats, chronic exposure to high levels of testosterone propionate (TP) increases aggression, nandrolone (ND) has little effect and stanozolol (ST) suppresses aggression. The present experiment tested whether the effects of TP, ND and ST on aggression and reproductive tissues are reversed following anabolic androgenic steroid (AAS) withdrawal. Gonadally intact males received TP, ND, ST or vehicle for 12 weeks. Injections were then discontinued. Aggression was tested 3 weeks (short term) and 12 weeks (long term) after withdrawal of AAS treatment, with either a gonadally intact or a castrated opponent in three different environments (home, opponent's and neutral cage). After short-term withdrawal, some parameters of aggression were significantly above control levels in TP males. There were no significant differences between ND or ST males and controls, though ST males showed the lowest levels of aggression. No significant differences between any of the groups were found after long-term withdrawal. Eighteen weeks after AAS withdrawal, serum testosterone (T) and LH levels were comparable to controls in all groups. Testes weights were at control levels in ST males, but significantly higher than controls in TP and ND males. Seminal vesicle weights were significantly elevated in TP males, but similar to controls in both ND and ST males. None of the prostate weights were significantly different from controls. These results suggest that aggression gradually returns to normal following withdrawal from AAS. Some, if not all, hormone levels and tissue weights return to normal, suggesting possible long-lasting effects of chronic AAS exposure.  相似文献   

13.
背景:有研究表明改构型酸性成纤维细胞生长因子是多功能生长因子,但其抗衰老作用至今尚未见报道。 目的:观察改构型酸性成纤维细胞生长因子对D-半乳糖致衰老大鼠脑组织、肝组织及血清中超氧化物歧化酶活力、丙二醛含量和抑制羟自由基能力的影响。 方法:选择成年Wistar大鼠皮下注射D-半乳糖建立衰老模型,建模成功后随机分为模型组、生理盐水对照组和改构型酸性成纤维细胞生长因子治疗组,另设正常对照组。改构型酸性成纤维细胞生长因子组按12 µg/kg剂量肌肉注射改构型酸性成纤维细胞生长因子,生理盐水对照组肌肉注射等量的生理盐水,模型组不作干预。 结果与结论:与模型组和生理盐水对照组相比,改构型酸性成纤维细胞生长因子治疗组脑组织、肝组织及血清中超氧化物歧化酶活力和抑制羟自由基能力均显著升高(P < 0.01或P < 0.05),丙二醛含量均显著降低(P < 0.01或P < 0.05)。结果证实,改构型酸性成纤维细胞生长因子可通过降低自由基,提高机体的抗氧化能力来发挥延缓衰老的作用。  相似文献   

14.
A battery of behavioral tasks in C57BL/6J mice was used to assess changes in affective components of behavior after systemic exposure to the anabolic-androgenic steroid (AAS) 17alpha-methyltestosterone (7.5 mg/kg). Gonadal weight in both sexes was reduced after 16 days of AAS exposure. Changes in discrete components of social behaviors were observed. No changes were recorded in the elevated plus-maze, the light-dark transition, and defensive behavior tests on exposure to 17alpha-methyltestosterone. When compared with controls, AAS-exposed females received a greater number of shocks, and AAS-exposed males displayed a shorter recovery time to consume water after a negative reinforcer in the modified Vogel conflict test. Results show that systemic exposure to a single AAS modified social behaviors, whereas minimal effects on anxiety-related behaviors were observed according to sex.  相似文献   

15.
Are androgens reinforcing? Androgenic-anabolic steroids (AAS) are drugs of abuse. They are taken in large quantities by athletes and others to increase performance, often with negative long-term health consequences. As a result, in 1991, testosterone was declared a controlled substance. Recently, Brower [K.J. Brower, Anabolic steroid abuse and dependence. Curr. Psychiatry Rep. 4 (2002) 377-387.] proposed a two-stage model of AAS dependence. Users initiate steroid use for their anabolic effects on muscle growth. With continued exposure, dependence on the psychoactive effects of AAS develops. However, it is difficult in humans to separate direct psychoactive effects of AAS from the user's psychological dependence on the anabolic effects of AAS. Thus, studies in laboratory animals are useful to explore androgen reinforcement. Testosterone induces a conditioned place preference in rats and mice, and is voluntarily consumed through oral, intravenous, and intracerebroventricular self-administration in hamsters. Active, gonad-intact male and female hamsters will deliver 1 microg/microl testosterone into the lateral ventricles. Indeed, some individuals self-administer testosterone intracerebroventricularly to the point of death. Male rats develop a conditioned place preference to testosterone injections into the nucleus accumbens, an effect blocked by dopamine receptor antagonists. These data suggest that androgen reinforcement is mediated by the brain. Moreover, testosterone appears to act through the mesolimbic dopamine system, a common substrate for drugs of abuse. Nonetheless, androgen reinforcement is not comparable to that of cocaine or heroin. Instead, testosterone resembles other mild reinforcers, such as caffeine, nicotine, or benzodiazepines. The potential for androgen addiction remains to be determined.  相似文献   

16.
The effects of systemic naloxone on pain behaviour in rats were examined in modified formalin test. Dilute formalin was subcutaneously injected in the plantar surface of the hindpaw, after which pain was rated according to behavioural criteria. Fifteen minutes after formalin injection, naloxone in various doses (10 micrograms/kg, 100 micrograms/kg, 300 micrograms/kg, 600 micrograms/kg, 800 micrograms/kg, 2000 micrograms/kg) or saline was intraperitoneally injected. Pain behaviour in naloxone injected and saline injected rats was not different. The findings are discussed in relation to previous reports about naloxone effects on different types of pain.  相似文献   

17.
In the present study, we evaluated the effects of single components of Ferula hermonis extract on female rat sexual behaviour. Ovariectomized rats hormonally primed with estradiol benzoate (1.5 or 10 microg/rat s.c.) and progesterone (500 microg/rat s.c.) were acutely treated by oral gavage with ferutinin, teferin and teferdin (2.5 mg/kg). Thereafter they were tested for: a) partner preference, b) receptivity, c) proceptivity, d) paced mating behaviour. In the partner preference test, the choice of the female for a sexually active male was not influenced by the different treatments. Similarly, during the paced mating test, the contact-return latencies as well as the percentage of exits from the male compartment were not different in control and treated rats. Therefore none of the three compounds showed the capacity to alter sexual motivation. On the other hand, ferutinin, but not teferin and teferdin, significantly inhibited female receptivity. These results suggest a primary role of ferutinin in the impairment of sexual behaviour elicited by F. hermonis extract in hormone primed-female rats.  相似文献   

18.
Adolescence in human males is a hormonally sensitive period when many adult behaviors develop, including sexual and aggressive behaviors. Using a rat model, the authors examined the effects of three anabolic-androgenic steroids (AAS) during puberty: testosterone, nandrolone, and stanozolol. Copulation, vocalizations, scent-marking, and aggression were tested following AAS exposure. Relative to gonadally intact controls, rats injected with testosterone showed a significant increase in scent-marking and aggression in the opponent's home cage. Nandrolone had no effect. Stanozolol significantly inhibited all behaviors. Results suggest that depending on the chemical structure of the steroid, AAS exposure during puberty affects several androgen-dependent behaviors. Because adolescence in humans is a period of hormonal change, abuse of AAS, particularly stanozolol, during this time may disrupt the establishment of normal adult behavior patterns.  相似文献   

19.
Previous studies have documented a decrease in the ability of neonatal hypothyroid animals to learn and habituate to maze tests, and an increase in spontaneous activity. However, there is little information about the effects of perinatal (i.e., prenatal and postnatal) hypothyroidism on behaviour. The present study was designed to assess whether perinatal hypothyroidism in rats induces alteration on acquisition and/or short- and long-term retention of a learned response in male Wistar rats. Perinatal hypothyroidism was induced by prolonged (E9-P21) exposure of pregnant and lactating dams to methimazole (administered orally in drinking water, 0.2 mg/ml). Cognitive function was tested at 50 days by means of a step-through passive avoidance task. The effects of perinatal hypothyroidism on the retention of the passive avoidance response are long lasting being, however, highly dependent on the retention after the original training. Our results showed that methimazole-treated rats performed more poorly when retention was tested at long-term (24 h and 7 days) retention interval. Instead, methimazole-treated rats showed longer retrieval latencies than the control ones did when retention was tested at short term (1 h).  相似文献   

20.
The aim of the present study was to examine possible long-term effects of the anabolic androgenic steroid (AAS), nandrolone decanoate (ND), on dominance in a provoking and competitive situation in sexually matured male rats. The experimental group (n=10) received daily injections of ND [15 mg/kg in a volume of 1 ml/kg subcutaneous (s.c.) injection for 14 days]. During the corresponding period, the controls (n=10) were given daily injections of an oil vehicle (1 ml/kg s.c.). All animals were tested in a competitive situation at four occasions after the end of the treatment period (week 5, 8, 11 and 14). Water-deprived pairs of rats, consisting of one ND-treated rat and one control, had to compete for access to water. The results showed that the ND-treated rats approached the water spout significantly more often compared to the controls. During the competition tests, the ND-treated rats spent more time drinking, an effect that was prominent for 11 weeks after the end of the treatment period. The ND-treated rats also displayed more frequently piloerection than the controls. The results indicate that ND has long-term effect on dominance in a provoking and competitive situation.  相似文献   

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