Journal of Animal Science, Vol 73, Issue 9 2834-2844, Copyright © 1995 by American Society of Animal Science

JOURNAL ARTICLE

Follicular atresia in pigs: measurement and physiology

H. D. Guthrie, R. W. Grimes, B. S. Cooper and J. M. Hammond
Germplasm and Gamete Physiology Laboratory, ARS, USDA, Beltsville, MD 20705, USA.

The physiological regulation of follicular atresia was investigated during the early luteal phase after ovulation and during altrenogest-synchronized preovulatory maturation in pigs (gilts). Apoptosis in dispersed granulosa cells was determined by flow cytometry. Apoptotic (A0) cells contain low, subdiploid amounts of DNA fluorescence. Follicles were classified biochemically as atretic or nonatretic based on the percentage of A0 (% A0) cells, atretic with > or = 10%, and nonatretic with < 10% A0 granulosa cells. The % A0 granulosa cells/follicle ranged from .02 to 89. Follicles containing debris in their isolated granulosa cells were classified as morphologically atretic. The morphological and biochemical criteria of atresia were in agreement for 224 of 248 follicles. Internucleosomal DNA cleavage, the hallmark of apoptosis, was determined by autoradiographic analysis of [32P]3'-end labeled DNA from granulosa cells. Densitometric analysis showed that optical density of [32P]3'-end labeled DNA fragments in the .18 to 20 kbp size range was correlated with the % A0 cells (R > .9, n = 22, P < .001). During altrenogest-synchronized preovulatory maturation, < 5% of large (> 6 mm in diameter) follicles were atretic. Among medium-sized follicles (3 to 6 mm) on d 1 and 3 of preovulatory maturation, only 17% were atretic, in contrast with d 5 when 87% were atretic. During the early luteal phase, atretic follicles/pig increased from 6% on d 5 to 50% on d 7 after estrus. Follicular fluid estradiol-17 beta concentration was greater (P < .001) in nonatretic than in atretic follicles on d 5 and 6 after estrus, but by d 7 estradiol-17 beta had decreased to a mean < 1 ng/mL in nonatretic and atretic follicles. The increase in apoptosis in granulosa cells and loss of estradiol-17 beta production in vivo indicated a high incidence of atresia among the first group of follicles grown after ovulation in pigs. These results indicate that apoptotic cell death was involved in degeneration of granulosa cells and atresia during two different stages of follicular development.

This article has been cited by other articles:

				T. Shimizu, K. Iijima, K. Miyabayashi, Y. Ogawa, H. Miyazaki, H. Sasada, and E. Sato Effect of direct ovarian injection of vascular endothelial growth factor gene fragments on follicular development in immature female rats Reproduction, November 1, 2007; 134(5): 677 - 682. [Abstract] [Full Text] [PDF]

				N. Sunak, D. F Green, L. R Abeydeera, L. M Thurston, and A. E Michael Implication of cortisol and 11{beta}-hydroxysteroid dehydrogenase enzymes in the development of porcine (Sus scrofa domestica) ovarian follicles and cysts Reproduction, June 1, 2007; 133(6): 1149 - 1158. [Abstract] [Full Text] [PDF]

				H. D. Guthrie The follicular phase in pigs: Follicle populations, circulating hormones, follicle factors and oocytes J Anim Sci, June 1, 2005; 83(13_suppl): E79 - 89. [Abstract] [Full Text] [PDF]

				H. Jiang, K. M. Whitworth, N. J. Bivens, J. E. Ries, R. J. Woods, L. J. Forrester, G. K. Springer, N. Mathialagan, C. Agca, R. S. Prather, et al. Large-Scale Generation and Analysis of Expressed Sequence Tags from Porcine Ovary Biol Reprod, December 1, 2004; 71(6): 1991 - 2002. [Abstract] [Full Text] [PDF]

				J. Uma, P. Muraly, S. Verma-Kumar, and R. Medhamurthy Determination of Onset of Apoptosis in Granulosa Cells of the Preovulatory Follicles in the Bonnet Monkey (Macaca radiata): Correlation with Mitogen-Activated Protein Kinase Activities Biol Reprod, October 1, 2003; 69(4): 1379 - 1387. [Abstract] [Full Text] [PDF]

				T. Shimizu, J.-Y. Jiang, K. Iijima, K. Miyabayashi, Y. Ogawa, H. Sasada, and E. Sato Induction of Follicular Development by Direct Single Injection of Vascular Endothelial Growth Factor Gene Fragments into the Ovary of Miniature Gilts Biol Reprod, October 1, 2003; 69(4): 1388 - 1393. [Abstract] [Full Text] [PDF]

				R. V. Knox, G. Vatzias, C. H. Naber, and D. R. Zimmerman Plasma gonadotropins and ovarian hormones during the estrous cycle in high compared to low ovulation rate gilts J Anim Sci, January 1, 2003; 81(1): 249 - 260. [Abstract] [Full Text] [PDF]

				J. Mao, G. Wu, M. F. Smith, T. C. McCauley, T. C. Cantley, R. S. Prather, B. A. Didion, and B. N. Day Effects of Culture Medium, Serum Type, and Various Concentrations of Follicle-Stimulating Hormone on Porcine Preantral Follicular Development and Antrum Formation In Vitro Biol Reprod, October 1, 2002; 67(4): 1197 - 1203. [Abstract] [Full Text] [PDF]

				J. Prange-Kiel, C. Kreutzkamm, U. Wehrenberg, and G. M. Rune Role of Tumor Necrosis Factor in Preovulatory Follicles of Swine Biol Reprod, September 1, 2001; 65(3): 928 - 935. [Abstract] [Full Text] [PDF]