Long term evaluation of functional and morphological bladder alterations on alloxan-induced diabetes and aging: experimental study in rats / Avaliação funcional e morfológica tardia de alterações na bexiga secundárias ao diabetes induzido por aloxano e no envelhecimento: estudo experimental em ratos

PURPOSE: to evaluate structural and functional effects of Alloxan- induced diabetes and aging on bladder of rats. METHODS: evaluations were performed in three groups: A - 8 weeks of age, B - 44 weeks of age, C - 44 weeks of age with alloxan-induced diabetes. Muscle layer thickness, extracellular matrix fibrosis and collagen were quantified on digital images of bladder samples. Cystometric evaluations before surgical vesical denervation (SVD), included maximum cystometric capacity (MCC), maximum bladder pressure (MBP), bladder contraction frequency (VCF), duration of bladder contraction (DC), threshold pressure (TP) and bladder compliance (BC). After SVD, maximum cystometric capacity (MCC), BC and maximum urethral closing pressure (MUCP) were also measured. RESULTS: Reduced extracellular matrix fibrosis concentration and contraction strength were found in the bladders of group C. Before SVD, bladder compliance was not different between groups. Alterations were observed in MCC after SVD. CONCLUSIONS: We did not notice smooth muscle hypertrophy in Alloxan-induced diabetic rats after 44 weeks. There was alteration in the total and relative amount of fibrosis and collagen. The cystometric studies support the idea that this morphological alterations are important to determine the different bladder functional patterns found in the aging and the Alloxan-induced diabetic animals.

OBJETIVOS: avaliar alterações estruturais e funcionais da bexiga de ratos machos, associadas ao diabetes induzido por aloxano e ao envelhecimento. MÉTODOS: três grupos de animais: A - 8 semanas de idade; B- 44 semanas de idade; C - 44 semanas de idade com diabetes induzido por aloxano, foram avaliados. Realizadas medidas de espessura da camada muscular, fibrose de matriz extracelular e quantidade de colágeno, através de análise de imagem digital dos tecidos. Realizados também testes cistométricos, antes da desnervação vesical cirúrgica (DVC), para avaliar capacidade vesical (CV), intensidade máxima de contração vesical (IMCV) e complacência vesical. Após a DVC, foram avaliadas capacidade vesical após a desnervação (CVAD), complacência vesical (CV) e pressão de perda uretral (PPU). RESULTADOS: não foi observada hipertrofia da camada muscular nas bexigas; houve diminuição da concentração de fibrose da matriz extracelular e diminuição da força contrátil, e aumento da capacidade vesical no grupo C. CONCLUSÕES: a atrofia da camadas muscular da bexiga esta relacionada ao diabetes induzido por aloxano. O envelhecimento, como fenômeno isolado, provoca alterações nos parâmetros funcionais, porém associado ao diabetes, gera alterações na IMCV, CV e CVAD. Existe correlação entre alterações estruturais e funcionais nos animais diabéticos após a desnervação.

Effect of denervation and ischemia reperfusion injury on serum nitric oxide levels in rats

To evaluate the effect of renal denervation and serum nitric oxide level with a different time course of renal ischemia-reperfusion injury. Thirty-six male Wistar rats were randomized into 6 groups. All rats underwent right nephrectomy to create a single kidney model. Renal denervated and innerved rats were subjected to renal clamping for 30-60 minutes. The study was performed in the Department of Anatomy, Akdeniz University, Antalya, Turkey, between June and November 2005. Combined effect of denervation and ischemia may caused significant increase in serum nitric oxide levels and decrease in glomerular filtration rates. Our results indicate that kidney denervation did not cause any changes in renal functions, but with ischemia it worsens the deleterious effect of ischemia-reperfusion injury, and causes a significant increase in serum nitric oxide levels

Effect of denervation on rat soleus muscle: light morphometric and electron microscopic study

This study described the light, morphometric and ultrastructure of denervated rat soleus muscle, with a particular emphasis on understanding the ultrastructural changes and cellular basis for the reduced restorative capacity of denervated muscle. The right hind limbs of adult male Wister rats were denervated for periods of one, two, three and four weeks and the samples were processed for light and electron microscopy. Atrophy of muscle fibers was prominent from the first week. At further periods of denervation, atrophy of all muscle fibers was seen most clear with morphometry. As denervation progressed, the morphology of individual muscle fibers varied. Most of muscle fibers contained well-organized myofilaments; whereas in others, local areas of sarcomeric disorganization were evident. Mitochondria became smaller and rounded, the elements of the sarcoplasmic reticulum proliferated and became more disorganized, the autophagic vesicles were well present in the cytoplasm of atrophic muscle fibers. The satellite cells did not show signs of activation at four weeks after denervation

Efeitos da desnervaçäo periférica sobre a formaçäo do calo ósseo: estudo experimental em ratos / Effects of the peripheral denervation on fracture healing: experimental study in rats

Foi feito estudo experimental em 24 ratos de raça Wistar, com 30 dias de vida. Foram produzidas fraturas fechadas na diáfise dos metatarsais de ambas as patas, ao mesmo tempo em que se procedeu à neurectomia ciática esquerda, ao nível de regiäo glútea. O processo de consolidaçäo das fraturas foi analisado através de estudo histológico nas 1ª, 2ª, 3ª e 6ª semanas após a produçäo da fratura, comparando-se o lado desnervado com o contralateral. A desnervaçäo ciática nao resultou em alteraçöes no processo de formaçäo do calo ósseo.