FSH AND LH LEVELS IN THE INTACT AND UNILATERALLY OVARIECTOMIZED CYCLING RAT

1972 ◽  
Vol 69 (2) ◽  
pp. 267-280 ◽  
Author(s):  
Richard D. Peppler
Keyword(s):  
Plasma Concentrations ◽  
Follicular Development ◽  
Slight Modification ◽  
Oestrous Cycle ◽  
Successive Cycle ◽  
Unilateral Ovariectomy ◽  
Subsequent Cycle ◽  
Intact Rats

ABSTRACT Intact 5-day cycling rats were killed between 8–10 a. m. on each day of the oestrous cycle; experimental rats were unilaterally ovariectomized (ULO) at 9 a. m. on day 1 (oestrus) and killed between 8 and 10 a. m. on days 2, 3, 4 or 1 of the subsequent cycle. Pituitary and plasma concentrations of FSH and LH were measured in both groups of rats. Pituitary FSH concentration was measured by the Steelman-Pohley method with slight modification; plasma FSH by the Igarashi-McCann assay and pituitary and plasma LH concentration by the OAAD method. In intact rats, pituitary FSH values remained constant for the first three days of the cycle, increased on day 4 and reverted to early cycle values by day 5. Plasma FSH increased between days 2 and 3 and days 5 and 1. Pituitary LH concentration remained the same for days 1 and 2; increased two-fold on days 3 and 4, and increased further by day 5. Plasma LH increased between days 2 and 3; other differences between successive cycle days were not apparent. Following ULO on day 1, pituitary FSH increased steadily, but not significantly, for the remaining cycle. Plasma FSH did not change from day 2 through day 1 of the subsequent cycle. Pituitary LH remained low on day 2, increased sharply by day 3 and decreased (50 %) by day 4. Plasma LH also increased between days 2 and 3. Other differences between successive days following unilateral ovariectomy on day 1 were not apparent. Correlation of gonadotrophin activity with follicular development suggests that the mechanism of compensatory ovulation in the rat may be one of an increase in time of exposure to a constant gonadotrophic level for the duration of the oestrous cycle rather than to increased levels of the gonadotrophin.

Follicular dynamics and secretion of inhibin and oestradiol-17β during the oestrous cycle of the hamster

1995 ◽  
Vol 146 (1) ◽  
pp. 169-176 ◽  
Author(s):  
H Kishi ◽  
K Taya ◽  
G Watanabe ◽  
S Sasamoto
Keyword(s):  
Plasma Levels ◽  
Marked Decrease ◽  
Plasma Concentrations ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
Antral Follicles ◽  
Follicular Maturation ◽  
Follicular Dynamics

Abstract Plasma and ovarian levels of inhibin were determined by a radioimmunoassay (RIA) at 3-h intervals throughout the 4-day oestrous cycle of hamsters. Plasma concentrations of FSH, LH, progesterone, testosterone and oestradiol-17β were also determined by RIAs. In addition, hamsters were injected at various times with human chorionic gonadotrophin (hCG) to determine the follicular development. The changes in plasma concentrations of FSH after injection of antisera to oestradiol-17β (oestradiol-AS) and inhibin (inhibin-AS) on the morning of day 2 (day 1=day of ovulation) were also determined. Plasma concentrations of inhibin showed a marked increase on the afternoon of day 1, remained at plateau levels until the morning of day 4, then increased abruptly on the afternoon of day 4 when preovulatory LH and FSH surges were initiated. A marked decrease in plasma concentrations of inhibin occurred during the process of ovulation after the preovulatory gonadotrophin surges. An inverse relationship between plasma levels of FSH and inhibin was observed when the secondary surge of FSH was in progress during the periovulatory period. Plasma concentrations of oestradiol-17β showed three increase phases and these changes differed from those of inhibin. Changes in plasma concentrations of oestradiol-17β correlated well with the maturation and regression of large antral follicles. Follicles capable of ovulating following hCG administration were first noted at 2300 h on day 1. The number of follicles capable of ovulating reached a maximum on the morning of day 3 (24·8± 0·6), and decreased by 0500 h on day 4 (15·0 ± 1·1), corresponding to the number of normal spontaneous ovulations. Plasma concentrations of FSH were dramatically increased within 6 h after inhibin-AS, though no increase in FSH levels was observed after oestradiol-AS. These findings suggest that changes in the plasma levels of inhibin during the oestrous cycle provide a precise indicator of follicular recruitment, and that the changes in plasma concentrations of oestradiol-17β are associated with follicular maturation. These findings also suggest that inhibin may play a major role in the inhibition of FSH secretion during the oestrous cycle of the hamster. Journal of Endocrinology (1995) 146, 169–176

scholarly journals Secretion of inhibin A, inhibin B and inhibin pro-alphaC during the oestrous cycle of the golden hamster (Mesocricetus auratus)

1999 ◽  
Vol 162 (3) ◽  
pp. 451-456 ◽  
Author(s):  
K Ohshima ◽  
H Kishi ◽  
M Itoh ◽  
G Watanabe ◽  
K Arai ◽  
...  
Keyword(s):  
Golden Hamster ◽  
Plasma Concentrations ◽  
Follicular Development ◽  
Early Morning ◽  
Oestrous Cycle ◽  
Inhibin B ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inhibin A ◽  
Negative Relationships ◽  
Plasma Oestradiol

Plasma concentrations of inhibin pro-alphaC, inhibin A and inhibin B were determined by enzyme-linked immunosorbent assay at 6 h intervals throughout the 4-day oestrous cycle of the golden hamster. Plasma concentrations of follicle-stimulating hormone (FSH) and oestradiol-17beta were also measured by radioimmunoassay during the oestrous cycle. Plasma concentrations of inhibin A increased from the early morning of day 1 (day 1=day of ovulation) and reached plateau levels at 0500 h on day 2. An abrupt increase in plasma concentrations of inhibin A was found at 1700 h on day 4, when the preovulatory FSH surge was observed. An increase in plasma concentrations of inhibin B occurred on day 1 and reached plateau levels at 1700 h on day 1. The levels remained elevated until 0500 h on day 4 and declined gradually by 2300 h on day 4. Plasma concentrations of inhibin pro-alphaC gradually increased with some fluctuation from day 1 to 1700 h on day 4 and then declined. Significant negative relationships were noted between plasma FSH and both dimeric forms of inhibin from day 1 to day 3. Significant positive relationships were found between plasma oestradiol-17beta and inhibin A or inhibin pro-alphaC throughout the oestrous cycle. In contrast, no significant relationship was found between plasma oestradiol-17beta and inhibin B. These findings suggest that both dimeric forms of inhibin play a role in the regulation of FSH secretion during follicular development. These findings also suggest that inhibin pro-alphaC could be secreted primarily by large follicles, and early atretic follicles could also be responsible for inhibin pro-alphaC secretion. On the other hand, the secretory pattern of dimeric inhibins might shift from inhibin B to inhibin A with follicular development.

EFFECT OF SUPPRESSION OF THE SURGE OF FOLLICLE-STIMULATING HORMONE WITH PORCINE FOLLICULAR FLUID ON FOLLICULAR DEVELOPMENT IN THE RAT

1981 ◽  
Vol 88 (1) ◽  
pp. 67-71 ◽  
Author(s):  
ANNE N. HIRSHFIELD ◽  
L. V. DE PAOLO
Keyword(s):  
Follicular Fluid ◽  
Follicle Stimulating Hormone ◽  
Follicular Development ◽  
Oestrous Cycle ◽  
Subsequent Cycle ◽  
Stimulating Hormone

To examine the manner in which the FSH surge of one oestrous cycle recruits follicles for ovulation in the subsequent cycle, porcine follicular fluid (PFF) was used to alter the pattern of endogenous FSH secretion during the periovulatory period. Ovaries of animals killed at oestrus or metoestrus were examined histologically for the presence of large follicles (greater than 400 μm in diameter) after treatment. Large follicles were absent in ovaries of all PFF-treated animals at oestrus, while control rats had an average of 2·7 large follicles per ovary. By metoestrus, however, ovaries of rats treated with PFF contained several large, healthy follicles. Only when PFF treatment was continued throughout the evening of oestrus was the appearance of large follicles prevented at metoestrus. Our results suggest that the prolonged oestrous portion of the FSH surge, rather than the pro-oestrous portion, is responsible for follicular recruitment during the normal oestrous cycle in the rat. They also indicate that compensatory follicular development occurs in response to the FSH rebound which has been shown to follow FSH suppression.

Immediate and delayed effects of heat stress on follicular development and its association with plasma FSH and inhibin concentration in cows

Reproduction ◽  
2000 ◽  
pp. 83-90 ◽  
Author(s):  
Z Roth ◽  
R Meidan ◽  
R Braw-Tal ◽  
D Wolfenson
Keyword(s):  
Heat Stress ◽  
Follicular Development ◽  
Oestrous Cycle ◽  
Low Fertility ◽  
Delayed Effect ◽  
Delayed Effects ◽  
Treatment Groups ◽  
Follicular Wave ◽  
Subsequent Cycle ◽  
Follicular Dynamics

The aim of this study was to characterize the immediate effects of heat stress on plasma FSH and inhibin concentrations, and its involvement in follicular dynamics during a complete oestrous cycle, and to examine a possible delayed effect of heat stress on follicular development. Holstein dairy cows were oestrous synchronized and randomly assigned to either cooled (n = 7) or heat-stressed (n = 6) treatment groups. During a complete oestrous cycle, control cows, which were cooled, maintained normothermia, whereas heat-stressed cows, which were exposed to direct solar radiation, developed hyperthermia. At the end of this oestrous cycle (treated cycle), both groups were cooled and maintained normothermia for the first 10 days of the subsequent oestrous cycle. Throughout this period, follicular development was examined by ultrasonography, and plasma samples were collected. During the second follicular wave of the treated oestrous cycle, a significantly larger cohort of medium sized follicles (6-9 mm) was found in heat-stressed cows than in cooled cows (P < 0.05). The enhanced growth of follicles in this wave in heat-stressed cows was associated with a higher plasma FSH increase which lasted 4 more days (days 8-13 of the oestrous cycle; P < 0.05), and coincided with a decrease in the plasma concentration of immunoreactive inhibin (days 5-18 of the oestrous cycle; P < 0.05). During the follicular phase (days 17-20 of the treated cycle), heat-stressed cows showed an increase in the number of large follicles (>/= 10 mm), and the preovulatory plasma FSH surge was significantly higher in heat-stressed cows than in cooled cows (P < 0.01). The effect of heat stress was also observed during the first follicular wave of the subsequent cycle: the postovulatory plasma FSH concentration was higher (P < 0.01), but fewer medium follicles developed, and the first follicular wave decreased at a slower rate in previously heat-stressed cows than in cooled cows (0.40 and 0.71 follicles per day, respectively). This study shows both immediate and delayed effects of heat stress on follicular dynamics, which were associated with high FSH and low inhibin concentrations in plasma. These alterations may have physiological significance that could be associated with low fertility of cattle during the summer and autumn.

Changes in inhibin-A (α-βA dimer) and total α inhibin in the peripheral circulation and ovaries of rats after gonadotrophin-induced follicular development and during the normal oestrous cycle

1995 ◽  
Vol 147 (2) ◽  
pp. 271-283 ◽  
Author(s):  
P A Fahy ◽  
C A Wilson ◽  
A J Beard ◽  
N P Groome ◽  
P G Knight
Keyword(s):  
Plasma Concentrations ◽  
Follicular Development ◽  
Serum Levels ◽  
Peripheral Circulation ◽  
Oestrous Cycle ◽  
Female Rats ◽  
Immature Female ◽  
Adult Rats ◽  
Inhibin A ◽  
Α Subunit

Abstract Recent modifications to a previously reported two-site IRMA have permitted the measurement of serum/plasma concentrations and ovarian contents of inhibin-A (α-βA dimer) in pregnant mare serum gonadotrophin (PMSG)treated immature female rats and adult rats throughout the 4-day oestrous cycle. For comparison, total α inhibin levels were also measured by α subunit-directed inhibin RIA and found to be at least tenfold higher (relative to the same 32 kDa bovine inhibin standard used to calibrate both assays). In immature female rats, serum levels of inhibin-A dimer and total α inhibin increased within 3 h of PMSG injection and rose in parallel over the next 48 h to values four- to fivefold higher than pretreatment levels. Ovariectomy led to a rapid and parallel fall in both inhibin-A dimer and total α inhibin; initial half-lives (±95% confidence intervals) were 22 ± 4 and 20 ± 5 min respectively. In adult rats, marked fluctuations in plasma concentrations and ovarian contents of inhibin-A dimer and total α inhibin occurred during the 4-day oestrous cycle, most notably between the morning of pro-oestrus and the morning of oestrus. Plasma levels of inhibin-A dimer and total α inhibin peaked on the afternoon of pro-oestrus just before the preovulatory gonadotrophin surge. After ovulation, both inhibin-A dimer and total α inhibin fell abruptly (two- to threefold by 0200 h on oestrus; P<0·001), while FSH showed a secondary rise which peaked at 0700 h on oestrus. Although IRMA- and RIA-derived inhibin values generally followed a similar pattern across the 4-day cycle (plasma: r=0·52, P<0·001; ovary: r=0·41, P<0·001), a transient rise in plasma and ovarian inhibin-A dimer was detected at 0700 h on oestrus (P<0·01) which was unaccompanied by a rise in total α inhibin. This rise in plasma inhibin-A dimer was probably responsible for terminating the post-ovulatory FSH surge since FSH levels declined steadily over the next 15 h. Overall, plasma inhibin-A dimer and FSH concentrations across the whole cycle were negatively correlated (r= −0·22, P<0·01) whereas no correlation existed between total α inhibin and FSH (r= −0·11, P=0·12). Journal of Endocrinology (1995) 147, 271–283

Studies of the oestrous cycle, oestrus and pregnancy in the koala (Phascolarctos cinereus)

Reproduction ◽  
2000 ◽  
pp. 49-57 ◽  
Author(s):  
SD Johnston ◽  
MR McGowan ◽  
P O'Callaghan ◽  
R Cox ◽  
V Nicolson
Keyword(s):  
Luteal Phase ◽  
Post Partum ◽  
Plasma Concentrations ◽  
External Genitalia ◽  
Oestrous Cycle ◽  
Phascolarctos Cinereus ◽  
Pregnant Females ◽  
Peripheral Plasma ◽  
The Mean ◽  
High Concentrations

As an integral part of the development of an artificial insemination programme in the captive koala, female reproductive physiology and behaviour were studied. The oestrous cycle in non-mated and mated koalas was characterized by means of behavioural oestrus, morphology of external genitalia and changes in the peripheral plasma concentrations of oestradiol and progestogen. The mean (+/- SEM) duration of the non-mated oestrous cycle and duration of oestrus in 12 koalas was 32.9 +/- 1.1 (n = 22) and 10.3 +/- 0.9 (n = 24) days, respectively. Although the commencement of oestrous behaviour was associated with increasing or high concentrations of oestradiol, there were no consistent changes in the morphology or appearance of the clitoris, pericloacal region, pouch or mammary teats that could be used to characterize the non-mated cycle. As progestogen concentrations remained at basal values throughout the interoestrous period, non-mated cycles were considered non-luteal and presumed anovulatory. After mating of the 12 koalas, six females gave birth with a mean (+/- SEM) gestation of 34.8 +/- 0.3 days, whereas the remaining six non-parturient females returned to oestrus 49.5 +/- 1. 0 days later. After mating, oestrous behaviour ceased and the progestogen profile showed a significant increase in both pregnant and non-parturient females, indicating that a luteal phase had been induced by the physical act of mating. Progestogen concentrations throughout the luteal phase of the pregnant females were significantly higher than those of non-parturient females. Parturition was associated with a decreasing concentration of progestogen, which was increased above that of basal concentrations until 7 days post partum.

PROLONGED RELEASE BY DIOESTROUS RATS OF FOLLICLE-STIMULATING HORMONE DURING THE PERIOD OF OVULATION INDUCED BY LUTEINIZING HORMONE RELEASING HORMONE

1979 ◽  
Vol 81 (1) ◽  
pp. 109-118 ◽  
Author(s):  
SHUJI SASAMOTO ◽  
SHIGEO HARADA ◽  
KAZUYOSHI TAYA
Keyword(s):  
Luteinizing Hormone ◽  
Plasma Concentrations ◽  
High Plasma ◽  
Oestrous Cycle ◽  
Prolonged Release ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Follicular Maturation ◽  
Lh Rh ◽  
Premature Ovulation

When 1·0 μg luteinizing hormone releasing hormone (LH-RH) was given i.v. three times at 1 h intervals from 17.00 to 19.00 h on the day of dioestrus (day 0) to regular 4 day cyclic rats, premature ovulation was induced the next morning (day 1) with the number of ova present comparable to normal spontaneous ovulation. The next spontaneous ovulation occurred on the morning of day 5, 4 days after premature ovulation induced by LH-RH. Plasma concentrations of FSH and LH showed transient rises and falls within 1 h of administration of LH-RH; concentrations of FSH in the plasma decreased from 20.00 h on day 0 but markedly increased again from 23.00 h on day 0 to 02.00 h on day 1 and these high levels persisted until 14.00 h on day 1, with only a small increase of plasma LH during this period. The duration of increased FSH release during premature ovulation induced by LH-RH treatment was 6 h longer than the FSH surge occurring after administration of HCG on day 0. Surges of gonadotrophin were absent on the afternoon of day 1 (the expected day of pro-oestrus) and the surges characteristic of pro-oestrus occurred on the afternoon of day 4 and ovulation followed the next morning. The pituitary content of FSH did not decrease despite persisting high plasma levels of FSH during premature ovulation induced by either LH-RH or HCG on day 0. The changes in uterine weight indicated that the pattern of oestrogen secretion from the day of premature ovulation induced by LH-RH to the day of the next spontaneous ovulation was similar to that of the normal 4 day oestrous cycle. When 10 i.u. HCG were given on day 0, an increase in oestrogen secretion occurred on day 2, 1 day earlier than in the group given LH-RH on day 0. This advancement of oestrogen secretion was assumed to be responsible for the gonadotrophin surges on day 3. Similar numbers of fully developed follicles were found by 17.00 h on day 2 after premature ovulation induced by either LH-RH or HCG, suggesting that the shorter surge of FSH during premature ovulation induced by HCG had no serious consequences on the initiation of follicular maturation for the succeeding oestrous cycle in these rats. Administration of LH-RH on day 0 had no direct effect on the FSH surge during premature ovulation. Secretory changes in the ovary during ovulation may be responsible for this prolonged selective release of FSH.

Ovarian follicular development during the follicular phase of oestrous cycle in manchega ewes with different ovulation rate

1996 ◽  
Vol 45 (1) ◽  
pp. 299 ◽  
Author(s):  
A.Gómez Brunet ◽  
A.López Sebastián ◽  
A.González de Bulnes ◽  
J.Santiago Moreno ◽  
M.García López
Keyword(s):  
Follicular Development ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
Ovulation Rate ◽  
Ovarian Follicular Development

Effect of undernutrition on uterine progesterone and oestrogen receptors and on endocrine profiles during the ovine oestrous cycle

2006 ◽  
Vol 18 (4) ◽  
pp. 447 ◽  
Author(s):  
C. Sosa ◽  
J. A. Abecia ◽  
F. Forcada ◽  
C. Viñoles ◽  
C. Tasende ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Binding Capacity ◽  
Plasma Concentrations ◽  
Progesterone Receptors ◽  
Cell Types ◽  
Oestrous Cycle ◽  
Receptor Expression ◽  
Embryo Survival ◽  
Igf I ◽  
Maintenance Requirements

In the present study, it was investigated whether undernutrition affected the binding capacity, immunoreactivity and mRNA expression for uterine oestrogen and progesterone receptors (ER and PR, respectively) in sheep, as well as whether the responses were associated with changes in plasma concentrations of progesterone (P4), oestradiol (E2), glucose, fatty acids, insulin, leptin and insulin-like growth factor (IGF)-I during the oestrous cycle. Twenty ewes were fed either 1.5 (C) or 0.5 (L) times their maintenance requirements and were killed on Day 5 or 14 of the cycle (Day 0 = oestrus). Compared with Group C, Group L had higher concentrations of non-esterified fatty acids and lower concentrations of insulin, leptin and IGF-I. Group L also had higher plasma concentrations of P4 during the final days of the luteal phase. At oestrus in both treatment groups, there were peaks in the concentrations of glucose, insulin and IGF-I. For ER and PR, transcript expression, binding capacity and immunoreactivity were higher on Day 5 than on Day 14 of the cycle. The binding capacities for ER and PR were lower in Group L than in Group C on Day 5. Group C showed more immunoreactive staining for ER than did Group L in two of five cell types, whereas no effect of treatment was observed for PR immunoreactivity. There was more PR mRNA in the uterine horn contralateral to the corpus luteum in Group C than in Group L ewes. We conclude that undernutrition impairs steroid receptor expression and binding capacity. This may alter the uterine environment and help explain the reductions in embryo survival.

Miniature ponies: 2. Endocrinology of the oestrous cycle

2008 ◽  
Vol 20 (3) ◽  
pp. 386 ◽  
Author(s):  
O. J. Ginther ◽  
M. A. Beg ◽  
A. P. Neves ◽  
R. C. Mattos ◽  
B. P. L. Petrucci ◽  
...  
Keyword(s):  
Maximum Concentration ◽  
Luteal Phase ◽  
Plasma Concentrations ◽  
Oestrous Cycle ◽  
Slow Increase ◽  
Lh Surge ◽  
Ovulatory Follicle ◽  
The Future ◽  
Three Phases

Plasma concentrations of FSH, LH, oestradiol and progesterone were studied daily during 12 interovulatory intervals and 21 periovulatory periods in nine Miniature ponies. The peak of the FSH surge that was temporally associated with emergence of the future ovulatory follicle occurred when the follicle was ~9 mm, compared with a reported diameter of 13 mm in larger breeds. The ovulatory LH surge involved a slow increase between Days 13 and 18 (ovulation = Day 0; 0.6 ± 0.1 ng day–1), a minimal increase or a plateau on Days 18 to 21 (0.04 ± 0.1 ng day–1), and a rapid increase after Day 21 (2.2 ± 0.4 ng day–1; P < 0.0001). The end of the plateau and the beginning of the rapid increase occurred on the day of maximum concentration in the oestradiol preovulatory surge. An unexpected mean increase and decrease in LH occurred (P < 0.04) on Days 5 to 9. Concentrations of oestradiol and progesterone seemed similar to reported results in larger breeds. Results indicated that in Miniature ponies the peak of the FSH surge associated with emergence of the future ovulatory follicle occurred at a smaller diameter of the future ovulatory follicle than in larger breeds, the ovulatory LH surge increased in three phases, and the ovulatory LH surge was followed by an LH increase and decrease during the early luteal phase.

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