The short length of the estrous cycle of rats makes them ideal for investigation of changes occurring during the reproductive cycle. The estrous cycle lasts four days and is characterized as: proestrus, estrus, metestrus and diestrus, which may be determined according to the cell types observed in the vaginal smear. Since the collection of vaginal secretion and the use of stained material generally takes some time, the aim of the present work was to provide researchers with some helpful considerations about the determination of the rat estrous cycle phases in a fast and practical way. Vaginal secretion of thirty female rats was collected every morning during a month and unstained native material was observed using the microscope without the aid of the condenser lens. Using the 10 x objective lens, it was easier to analyze the proportion among the three cellular types, which are present in the vaginal smear. Using the 40 x objective lens, it is easier to recognize each one of these cellular types. The collection of vaginal lavage from the animals, the observation of the material, in the microscope, and the determination of the estrous cycle phase of all the thirty female rats took 15-20 minutes.Key words: estrous cycle, rat, cytology, smear. RESUMODeterminação das fases do ciclo estral em ratas: considerações úteis Em razão da curta duração de seu ciclo estral, ratas constituem bom modelo para o estudo das alterações que ocorrem durante o ciclo reprodutivo. O ciclo estral de ratas tem duração média de quatro ou cinco dias e é caracterizado por quatro fases, proestro, estro, metaestro e diestro, as quais podem ser determinadas pelos tipos celulares observados no esfregaço vaginal. Como a coleta da secreção vaginal e o uso de material corado geralmente são demorados, o objetivo deste trabalho foi fornecer aos pesquisadores algumas considerações úteis para a determinação das fases do ciclo estral de maneira rápida e prática. A secreção vaginal de trinta ratas foi coletada diariamente pela manhã, durante um mês, e o lavado vaginal não corado foi observado a fresco, em microscópio ótico, sem a utilização das lentes do condensador. O uso das objetivas de aumento de 10 vezes facilita a análise da proporção entre os três tipos celulares presentes no material. O uso das objetivas de aumento de 40 vezes permite o reconhecimento de cada um dos tipos celulares. Descrevemos o método utilizado, no qual a coleta do lavado vaginal, a observação do material e a identificação das fases do ciclo estral de 30 ratas podem ser realizados em 15-20 minutos.Palavras-chave: ciclo estral, ratas, citologia, esfregaço.

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This study indicated that nandrolone, whether associated with resistance training or not, induces cardiac hypertrophy, which is associated with enhanced collagen content, re-expression of fetal genes the in left ventricle, and impaired diastolic and systolic function.

Abstract-The effect of anaerobic physical training and nandrolone treatment on the sensitivity to phenylephrine in thoracic aorta and lipoprotein plasma levels of rats was studied. Sedentary and trained male Wistar rats were treated with vehicle or nandrolone (5 mg/kg IM; twice per week) for 6 weeks. Training was performed by jumping into water (4 sets, 10 repetitions, 30-second rest, 50% to 70% body weight load, 5 days/week, 6 weeks). Two days after the last training session, the animals were killed and blood samples for lipoprotein dosage were obtained. Thoracic aorta was isolated and concentration-effect curves of phenylephrine were performed in intact endothelium and endothelium-denuded aortic rings in the absence or presence of N G -L-arginine-methyl ester. No changes were observed in endotheliumdenuded aortic rings. However, in endothelium-intact thoracic aorta, anaerobic physical training induced subsensitivity to phenylephrine (pD 2 ϭ7.11Ϯ0.07) compared with sedentary group (7.55Ϯ1.74), and this effect was canceled by the inhibition of nitric oxide synthesis. No difference was observed between trained (7.22Ϯ0.07) and sedentary (7.28Ϯ0.09) groups treated with nandrolone. Anaerobic training induced an increase in high-density lipoprotein levels in vehicle-treated rats, but there were no changes in nandrolone-treated groups. Training associated with nandrolone induced an increase in low-density lipoprotein levels but no change in the other groups. If altering endotheliumdependent vasodilatation is considered to be a beneficial adaptation to anaerobic physical training, it is concluded that nandrolone treatment worsens animals' endothelial function, and this effect may be related to lipoprotein blood levels. Key Words: aorta Ⅲ endothelium Ⅲ exercise Ⅲ lipoproteins Ⅲ nitric oxide Ⅲ phenylephrine Ⅲ rats A nabolic androgenic steroids (AAS) are formed from testosterone or one of its derivatives and present both anabolic and androgenic effects. Although the therapeutic indications of AAS are hypogonadism and protein metabolism deficiency, high doses of AAS are frequently used by persons in good health to improve physical performance and appearance, and this practice results in serious health risks. 1 With regard to the cardiovascular system, it is well known that AAS can cause stroke, 2 ischemic heart disease, myocardial infarction, 3 electrocardiographic alterations, 4 and sudden cardiac death. 5 However, there are few studies about their effects on vascular reactivity. Ferrer et al 6 observed an inhibition of endothelium-dependent and endotheliumindependent relaxation in the aortic rings of rabbits treated with nandrolone. Vasoconstrictor responses to angiotensin and tyramine, but not to noradrenaline, and vasodepressor responses to acetylcholine are reduced in testosterone-treated dogs. 7 Although it is well documented that postexercise hypotension results from a decrease in systemic vascular resistance after aerobic exercise, both in humans and animals, 8 there are no data about the vascular effects of anaero...

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RESUMOOs esteróides anabólicos androgênicos (EAA) são compostos formados a partir da testosterona ou um de seus derivados, sendo amplamente utilizados por desportistas amadores e profissionais com o objetivo de melhorar a performance atlética. Entretanto, a literatura a respeito da relação entre EAA e hipertrofia muscular é controversa. O objetivo deste estudo foi avaliar os efeitos da nandrolona e do treinamento físico sobre a hipertrofia muscular. Ratos Wistar machos receberam injeção i.m. de DecaDurabolin® ou veículo durante 6 semanas. Os animais dos grupos treinados foram submetidos a treinamento físico resistido, através de sessões de saltos em meio líquido. Os animais sedentários e treinados foram sacrificados após anestesia e o músculo sóleo retirado para quantificação de proteínas totais e DNA. Ao final do tratamento, os animais treinados tratados com veículo ou EAA apresentaram menor peso corporal do que os respectivos grupos sedentários. Não foram observadas diferenças estatísticas na concentração de proteínas totais e na razão peso muscular/peso corporal entre os grupos experimentais. O grupo treinado tratado com EAA apresentou concentração de DNA significativamente menor do que o grupo treinado veículo. A administração de decanoato de nandrolona não promoveu hipertrofia do músculo sóleo, nem mesmo quando associada ao treinamento físico resistido. ABSTRACT Nandrolone Administration Does Not Promote Hypertrophy of Soleus Muscle in Rats.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.

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