ABSTRACT
SUMMARY: The present study was undertaken to elucidate ultrastructural changes in development of parotid salivary gland of buffalo during different stages of prenatal life. The ultrastructural studies revealed that the cytoplasm of acinar cells was filled with mitochondria, rough endoplasmic reticulum and Golgi complex in mid and late foetal age groups. Medium electron dense secretory granules first appeared in the acinar cells of parotid gland at 30 cm CVRL (141st day). However, at 49.5 cm CVRL (185th day) two types of electron dense granules were identified on basis of granule density viz., dark and light. The dark electron dense granules were more in number, whereas light granules were comparatively less having electron lucent content within them was identified. The mean diameter of dark and light granules was measured about 0.45±0.1 µm and 0.30±0.1 µm, respectively, which showed that the dark granules were comparatively larger in size. The secretory granules were increased in number during the late foetal age group. The myoepithelial cells were located at the base of the acinar cells as well as intercalated and striated ducts, and were stellate in shape. The ultrastructure of myoepithelial cell revealed parallel stream of myofilaments in the cytoplasm and its processes. Lipofuscin pigments were also observed in between the acinar cells of parotid gland.
RESUMEN: El estudio se realizó para elucidar los cambios ultraestructurales en el desarrollo de la parótida del búfalo durante las diferentes etapas de la vida prenatal. Los estudios ultraestructurales revelaron que el citoplasma de las células acinares estaba saturado de mitocondrias, de retículo endoplasmático rugoso y Complexo golgiensis en las edades fetal media y tardía. Se observó un número mayor de gránulos oscuros densos de electrones, mientras que los gránulos ligeros fueron comparativamente menor en número con contenido de electrones. El diámetro medio de gránulos oscuros y ligeros se midió aproximadamente 0,45 / pm 0,1 / mu m y 0,30 / pm 0,1 / mu m, respectivamente, lo que mostró que los gránulos oscuros eran comparativamente mayores en tamaño. Los gránulos secretores aumentaron en número durante el último grupo de edad fetal. Las células mioepiteliales se localizaron en la base de las células acinares, así como en conductos intercalados y estriados, y tenían una forma estrellada. La ultraestructura de las células mioepiteliales reveló una corriente paralela de miofilamentos en el citoplasma y sus procesos. También se observaron pigmentos de lipofuscina entre las células acinares de la glándula parótida.