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פותח על ידי קלירמאש פתרונות בע"מ -
Studies in vivo and in vitro on the initiation of follicle growth in the bovine ovary
Year:
1997
Authors :
בראב-טל, רות
;
.
Volume :
109
Co-Authors:
Braw-Tal, R., Department of Ruminant Reproduction, Institute of Animal Science, Volcani Center, Bet Dagan 50 250, Israel
Yossefi, S., Department of Ruminant Reproduction, Institute of Animal Science, Volcani Center, Bet Dagan 50 250, Israel
Facilitators :
From page:
165
To page:
171
(
Total pages:
7
)
Abstract:
Histological sections prepared from cortical parts of 25 bovine ovaries were used to study initiation of follicle growth in vivo. Small follicles were measured and characterized. Initiation of follicle growth consisted of two distinct consecutive phases. The first phase was characterized by transformation of granulosa cells from a flattened to a cuboidal shape and by their proliferation. In the second phase an increase in the number of granulosa cells was accompanied by a rapid increase in the size of the oocyte. Oocytes commenced growth when there were at least 40 granulosa cells in the largest cross-section (fourth generation of follicle cells). The oocyte diameter increased from 29.74 ± 0.30 μm (mean ± SEM) in primordial follicles to 92.90 ± 4.50 μm in small antral follicles. The zona pellucida first appeared as an island of periodic acid-Schiff positive material in small preantral follicles, but formed a complete ring around the oocyte when the late preantral stage was reached. Organ culture of ovarian cortical explants was used to study initiation of follicle growth in vitro. Within 2 days of culture most of the primordial follicles entered the growth phase: granulosa cells changed from a flattened to a cuboidal shape and entered S-phase as demonstrated by autoradiography after [3H]thymidine incorporation. On day 2, 48.6% of follicles were labelled compared with 3% on day 0. Follicle growth started in the absence of gonadotrophins, in the serum-free medium, confirming the notion that gonadotrophins are not essential for this process. The culture system used here will be helpful in the study of the involvement of putative factor(s) in the initiation of follicle growth in large domestic animals.
Note:
Related Files :
Animals
animal tissue
cattle
cell cycle s phase
Female
Granulosa Cells
Oocytes
Ovarian Follicle
ovary
עוד תגיות
תוכן קשור
More details
DOI :
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
23150
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:57
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Scientific Publication
Studies in vivo and in vitro on the initiation of follicle growth in the bovine ovary
109
Braw-Tal, R., Department of Ruminant Reproduction, Institute of Animal Science, Volcani Center, Bet Dagan 50 250, Israel
Yossefi, S., Department of Ruminant Reproduction, Institute of Animal Science, Volcani Center, Bet Dagan 50 250, Israel
Studies in vivo and in vitro on the initiation of follicle growth in the bovine ovary
Histological sections prepared from cortical parts of 25 bovine ovaries were used to study initiation of follicle growth in vivo. Small follicles were measured and characterized. Initiation of follicle growth consisted of two distinct consecutive phases. The first phase was characterized by transformation of granulosa cells from a flattened to a cuboidal shape and by their proliferation. In the second phase an increase in the number of granulosa cells was accompanied by a rapid increase in the size of the oocyte. Oocytes commenced growth when there were at least 40 granulosa cells in the largest cross-section (fourth generation of follicle cells). The oocyte diameter increased from 29.74 ± 0.30 μm (mean ± SEM) in primordial follicles to 92.90 ± 4.50 μm in small antral follicles. The zona pellucida first appeared as an island of periodic acid-Schiff positive material in small preantral follicles, but formed a complete ring around the oocyte when the late preantral stage was reached. Organ culture of ovarian cortical explants was used to study initiation of follicle growth in vitro. Within 2 days of culture most of the primordial follicles entered the growth phase: granulosa cells changed from a flattened to a cuboidal shape and entered S-phase as demonstrated by autoradiography after [3H]thymidine incorporation. On day 2, 48.6% of follicles were labelled compared with 3% on day 0. Follicle growth started in the absence of gonadotrophins, in the serum-free medium, confirming the notion that gonadotrophins are not essential for this process. The culture system used here will be helpful in the study of the involvement of putative factor(s) in the initiation of follicle growth in large domestic animals.
Scientific Publication
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