Relative Abundance of Cell Organelles in Steroidogenic Cells of Corpus Luteum of Goat in Different Reproductive Phases

Variations in relative abundance of different cell organelles of steroidogenic cells from seven categories of goat corpus luteum viz. small (1-5 days), medium (6-10 days), large (11-15 days), regressing (16-21 days), previous cycle, penultimate cycle and pregnancy (<30 days), have been analysed. In granulosa luteal cells, smooth endoplasmic reticulum variations were not prominent. Rough endoplasmic reticulum increased from small to large category and was most abundant in corpus luteum of pregnancy. The number of mitochondria, Golgi complex and secretory granules increased from small to large category. The maximum frequency was observed during the pregnancy. Vesicles were prominent in the previous and penultimate categories. The numbers of lipid droplets were maximum in corpus luteum of the previous cycle followed by the regressing category while lysosomes out numbered in corpus luteum of the penultimate cycle. In theca luteal cells, smooth endoplasmic reticulum and number of mitochondria increased from the small to large category and maximum numbers were observed during the pregnancy. Golgi complexes were abundant in corpora lutea of the large category and that of the pregnancy while vesicles showed their preponderance in corpus luteum of the penultimate category. Numbers of lipid droplets were more in corpus luteum of the previous cycle. Lysosomes were abundant in number in theca luteal cells of corpus luteum of the regressing category. Secretory granules were higher in number in corpora lutea of the large and pregnancy categories. These variations in relative abundance of cell organelles in steroidogenic cells shall be discussed in relation to their physiological obligations and endocrine profile at specific stage of reproductive cycle.