Morphometric analysis of small follicles in the ovary of the musk shrew (Suncus murinus L.) at different ages.
On the basis of morphological characteristics of granulosa cells surrounding the oocyte, the small follicles (Class 1) in the ovary of the musk shrew were classified into four groups: Type B (flattened cells), Type B/C (mixture of flattened and cuboidal cells), Type C (single layer of cuboidal cells), and Type D (more than one to two layers of cuboidal cells without epitheloid cells in the theca). The pattern of small follicular development was characterized by a short early dormant followed by a rapid growth phase. Initiation of follicular growth commenced at intermediate stage between large Type B and Type B/C follicles. Types B, B/C, and C were present in the ovary on Day 0 after birth, whereas Type D first appeared on Day 3 after birth. The total population of small follicles and the number of each type of follicle decreased with increasing age. In all age groups investigated, the total number of small follicles and the number of follicles of Types B, B/C, and C in the left ovary were significantly higher compared with those in the right ovary. The percentage of Type B follicles decreased with increasing age, while the percentages of Types B/C, C, and D increased. A positive correlation between the percentage of Type B and a negative correlation between the percentages of Types B/C, C, and D and the total small ovarian follicular population indicate the operation of an intraovarian regulation of some early steps of follicular growth.
Mohanty
N
N
Department of Zoology, Utkal University, Bhubaneswar, India.
Chainy
G B
GB
D000375:Aging / Q000473:pathology*; D000818:Animals; D005260:Female; D007700:Kinetics; D006080:Ovarian Follicle / Q000033:anatomy & histology* / Q000502:physiology; D012788:Shrews / Q000033:anatomy & histology*