Mitotic proliferation in the ovary of the normal mature guinea pig treated with colchicine

Schmidt, Ida G.

doi:10.1002/aja.1000710205

Cited by 26 publications

(9 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1C). As previously reported by Schmidt (1942) in the guinea pig and Hirshfield (1986) in the rat, mitotic activity was very low in preovulatory follicles.…”

Section: Growth Of Folliclessupporting

confidence: 84%

Dynamics of follicular growth and atresia of large follicles during the ovarian cycle of the guinea pig: Fate of the degenerating follicles, a quantitative study

et al. 1995

View full text Add to dashboard Cite

show abstract

“…1C). As previously reported by Schmidt (1942) in the guinea pig and Hirshfield (1986) in the rat, mitotic activity was very low in preovulatory follicles.…”

Section: Growth Of Folliclessupporting

confidence: 84%

Dynamics of follicular growth and atresia of large follicles during the ovarian cycle of the guinea pig: Fate of the degenerating follicles, a quantitative study

et al. 1995

View full text Add to dashboard Cite

show abstract

“…Follicular sizes were determined with an ocular micrometer by measuring the largest follicular diameter through a section containing the ovum. Criteria for classification of follicular types were a modifica tion of those described by Schmidt (1942) and expanded by Williams (1956). In the present study, follicles described by Williams 1956 as being in the earliest and intermediate stages of atresia were considered early atretic follicles (fig.…”

Section: Methodssupporting

confidence: 41%

Effects of Gonadotropins on Follicular Development, Ovulation, and Atresia in the Mature Guinea Pig

Rawson¹,

Galey²,

Weinberg³

et al. 1979

Horm Res

View full text Add to dashboard Cite

The induction of follicular growth, ovulation, and atresia by heterologous gonadotropic preparations was studied late in the reproductive cycle of the adult female guinea pig. Human chorionic gonadotropin (HCG) administration (10 IU) 12 days following the first signs of opening of the vaginal membrane was found to stimulate ovulation within 24 h in all animals studied, as evidenced by recovery of ova from their oviducts as well as the presence of postovulatory follicles in their ovaries. Histologically, ovaries of animals receiving HCG exhibited atretic changes in most of the follicles smaller than 999 µmin diameter. Pregnant mares serum gonadotropin (PMSG, 10 IU) administered on days 9 and 10 of the cycle was not sufficient to stimulate ovulation in this species although histological changes in the follicular complement were observed. Administration of PMSG prior to the HCG appeared to have an inhibitory effect on ovulation induction. Follicles luteinizing with entrapped ova were seen in all groups receiving exogenous gonadotropin, although they were most prevalent in the animals receiving the maximum total gonadotropin doses (i.e. PMSG + HCG).

show abstract

“…The data show that the growth of ovine ovarian follicles prior to the final preovulatory enlargement follows a well defined pattern which, on the basis of changes in the mitotic index of the granulosa with change in size of follicle, bears a general similarity to that occurring in the rat (Lane and Davis 1939), guinea pig (Schmidt 1942) and cow (Rajakoski 1960). Irrespective of the stage of oestrous cycle, the growth rate was slow in follicles up to about 0·4 mm in diameter and then accelerated until it reached a maximum in follicles of about 0·7 mm diameter.…”

Section: Discussionmentioning

confidence: 45%

The Pattern of Follicular Growth and Atresia in the Ovine Ovary

Turnbull¹,

Braden²,

Mattner³

1977

Aust. Jnl. Of Bio. Sci.

153

View full text Add to dashboard Cite

The ovaries of 21 2-year-old Merino ewes at various stages of the oestrous cycle were serially sectioned and all follicles > 0·5 mm in diameter were counted and measured. The mean number of normal follicles > 0·5 mm in diameter was 19· 9 per ewe, of which 8·7 were > 1 mm in diameter. The mean numbers of follicles > 0·5 mm in diameter in 'early', 'advanced' and 'late' stages of atresia were 4· 6, 9· 0 and 12· 3 respectively. Early atresia was rarely seen in follicles < 1 mm in diameter; the greatest incidence was in follicles of diameter 1· 5-2' 5 mm.Volumes of the granulosa, theca interna and antrum were calculated for all follicle sizes and the mitotic index of the granulosa and theca determined. Follicles were classified according to granulosa volume, each class having twice the volume of the preceding class. Estimates of the doubling time of the granulosa were made from the mitotic index and an estimate of mitotic time (0'43 h) obtained by use of colchicine on two other ewes. In all ewes, irrespective of day of oestrous cycle, the rate of growth was slow in follicles < 0·4 mm in diameter; above this size it accelerated to a maximum (doubling time 26-30 h) in follicles O· 7-2 mm in diameter. It was estimated that, on average, a follicle takes about 5 days to grow from 0·5 to 2·2mm diameter, and a further 4 days to reach 4·5 mm diameter. The number of follicles entering the rapid growth phase was estimated to be 3-4 per day. The present data do not support any particular 'wave' theory of follicular development, but indicate that follicles are growing or regressing asynchronously at any given time during the luteal stage of the oestrous cycle.At 48 h after treatment of two ewes with PMS gonadotrophin (PMSG), the number of follicles > 0·5 mm in diameter was increased, the greatest proportional increase being in those > 3·5 mm in diameter. Relatively few follicles were undergoing early atresia. At 18 h after RCG treatment (given 48 h after PMSG to two ewes) all follicles> 3·5 mm in diameter were undergoing luteinization and two-thirds of the follicles between 1 and 3·5 mm in diameter were undergoing early atresia.

show abstract

Mitotic proliferation in the ovary of the normal mature guinea pig treated with colchicine

Cited by 26 publications

References 6 publications

Dynamics of follicular growth and atresia of large follicles during the ovarian cycle of the guinea pig: Fate of the degenerating follicles, a quantitative study

Dynamics of follicular growth and atresia of large follicles during the ovarian cycle of the guinea pig: Fate of the degenerating follicles, a quantitative study

Effects of Gonadotropins on Follicular Development, Ovulation, and Atresia in the Mature Guinea Pig

The Pattern of Follicular Growth and Atresia in the Ovine Ovary

Contact Info

Product

Resources

About