Cytochemical changes in spinal cord and testis of mice during starvation

The effect of starvation on the content and distribution of RNA, proteins and glycogen of spinal cord and testis of mice was studied. Spinal cord and testis were taken from mice, non-starved and after one, two and three days of total starvation. In the neurons of the spinal cord, starvation decreased RNA and proteins early in the fast, decreases in glycogen occurred more slowly, late in the fast. In the testis there was no obvious decrease in RNA and proteins content and a very slight decrease of the glycogen granules, i.e. the mice conserve testis RNA, proteins and glycogen during prolonged starvation. It has been found that the effect of starvation on RNA, protein and glycogen of the testis and spinal cord was variable

electron microscope study of the skeletal and ventricle muscles of the tortoise

Various structural aspects of tortoise striated and ventricle muscle fibers nuclei, myofibrils, sarcoplasmic reticulum, such as sarcolemma, nuclei, myofibrils, sarcoplasmic reticulum, mitochondria, glycogen and fats are described. 1- The sarcolemma of the tortoise striated muscle fibers is defined with difficulty, while that of the cardiac muscle fibers is well defined. 2- The nuclei were described. Aggregations of densely stained chromatin are more common in the nucleus of striated muscle fibers. Small chromatin particles of various densities are scattered throughout the nuclear interior of ventricle muscle fibers. 3- Myofibrils in both muscle fibers vary in width and are poorly separated. 4- The myocfibrils in both muscle fibers show the classical regions and lines quite distinctly. H band is more obvious in ventricle muscle fibers than in striated muscle fibers. No M line is seen in tortoise striated muscle. 5- The intercalated discs of the tortoise ventricular muscle are simple, small in size and vary in width. 6- Tortoise muscles have very little sarcoplasmic reticulum. 7- The tortoise striated muscle fibers are recognized by the relative sparseness of mitochondria, while the ventricle muscle fibers contain numerous mitochondria, with numerous closely packed cristae glycogen particles are numerous, scattered throughout the muscle fibers, but concentraction of the granules occurs between the myofibrils especially at the I band and in the sarcoplasm at the poles of the nucleus. Fat which is represented by vacuoles is normally present in the sarcoplasm and are more numerous in the striated muscle fibers than in the cardiac muscle fibers