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

Morphology of the apical surface of endometrium on 1st, 6th and 22nd days of pregnancy in rats [Transmission and scanning electron microscopic study]

Morphology of the apical surface of the luminal epithelial cells of the endometrium of the rats on the 1st, 6th and 22nd days of pregnancy was examined by transmission and scanning electron microscopes. Twenty adult female and five adult male rats were used in this study. The animals were subsequently euthanized on either the 1st, 6th and 22nd days of pregnancy [term=23 days]. Using transmission electron microscope, the microvilli covering the apical surface of the luminal epithelial cells were long and irregularly spaced on the 1st day of pregnancy. They became shorter in length, numerous fewer in number and showed pinopods on the 6th day of pregnancy. Finally, they became numerous, long and slender on the 22nd day of pregnancy. Using the scanning electron microscope, it was observed that the uterine luminal epithelium was covered with long and slender microvilli on the 1st day of pregnancy. As pregnancy advanced, they became shorter and sparsely distributed with the presence of membranous protrusions on the 6th day of pregnancy. Late in pregnancy, on the 22nd day, the microvilli became longer and more numerous but no membranous protrusions could be observed