A possible role for prolactin in control of steroid secretion by the human Graafian follicle

McNatty, Kenneth P.; Sawers, R. S.; McNeilly, A. S.

doi:10.1038/250653a0

Cited by 482 publications

(132 citation statements)

References 12 publications

Supporting

Mentioning

116

Contrasting

Unclassified

Order By: Relevance

“…Binding sites for PRL have been demonstrated in rat (Richards and Williams 1976), bovine and human ovarian tissue (Poindexter et al 1979). It has been proposed that this peptide may regulate progesterone production by human granulosa cells (McNatty et al 1974), and that the elevated levels of PRL in human follicular fluid may be sufficient to suppress granulosa cell progesterone production. No such effects could be found in the present experiments.…”

Section: Discussionmentioning

confidence: 99%

“…Firstly, at the hypothalamo-pituitary level, no conclusive evidence has been produced which relates high PRL levels to the impairment of the feedback relationships of oestrogen and LH despite strong evidence that the presence of the calf per se, perhaps in association with other stressful factors, is often associated with prolonged postpartum anoestrus. Secondly, in view of the reported regulatory action of PRL on luteal cell LH receptors (Richards and Williams 1976) and the inhibitory effect of high concentrations of PRL on progesterone secretion by cultured human granulosa cells (McNatty et al 1974), it seems possible that the site for the disruption of ovarian function in cattle may lie within the ovary.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Modulation of Functional Capacity of Small Ovarian Follicles in the Post-partum Cow by Prolactin

Weiss¹,

Nancarrow²,

Dt³

et al. 1981

Aust. Jnl. Of Bio. Sci.

View full text Add to dashboard Cite

This study was undertaken to examine the possibility that the prolonged anovulatory period frequently experienced by the post-partum cow is due to a disruption of function at the ovarian level promoted by the high, suckling-induced, blood prolactin concentrations. Fifteen cows, less than 35 days post partum, were allocated to three groups (1, 3 and 5) and given no hormonal treatment, prostaglandin plus pregnant mare serum gonadotrophin (PMSG) treatment or injected with 2-bromo-ex-ergocryptine to reduce circulating prolactin levels. Ten synchronized cyclic cows were allocated to two groups (2 and 4) and given prostaglandin or prostaglandin plus PMSG treatment. All cows were ovariectomized 1 or 2 days after treatment and Graafian follicles less than 9 mm in diameter were selected after dissection from the ovaries. The follicles were cultured for 18 h with or without prolactin (1 fLgfml) and steroid accumulation in the culture medium estimated. The follicles were then separated into theca and granulosa which were incubated for 40 min with LH (1 fLgfml) or FSH (5 fLgfml). Cyclic AMP concentrations were estimated as an indication of tissue responsiveness to gonadotrophins.The secretion of oestradiol-17 p, progesterone, testosterone or androstenedione during 18 h culture did not differ between follicles isolated from post-partum or cyclic cows. The presence of prolactin in the culture medium had no overall effect on steroid secretion although some specific effects within each group were noticed. Incubation with LH increased cyclic AMP levels in the theca but the granulosa did not respond. Likewise FSH increased cyclic AMP levels in granulosa preparations but not in theca. There were no differences in response between post-partum and cyclic cows, but exposure of the follicles to prolactin in vitro did significantly reduce the LH-induced increase in cyclic AMP levels in isolated theca.We have concluded that endogenous prolactin may modify but does not inhibit the resumption of ovarian function following parturition in the beef cow.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Modulation of Functional Capacity of Small Ovarian Follicles in the Post-partum Cow by Prolactin

Weiss¹,

Nancarrow²,

Dt³

et al. 1981

Aust. Jnl. Of Bio. Sci.

View full text Add to dashboard Cite

show abstract

“…However, their treatment with bromocriptine brought about a marked fall in plasma PRL to levels below assay sensitivity (2ng/ml). Such a low level of PRL may cause defective progesterone synthesis as described by McNatty et al (1974). To our knowledge, there have been no reports of a spontaneous pathologic hypoprolactinemic condition leading to infertility.…”

mentioning

confidence: 91%

“…In the present study it is clearly demonstrated that the PRL level in the SLP is lower than that found in the normal cycle. McNatty et al (1974) reported that the production of progesterone by human granulosa cells in vitro requires an adequate concentration of PRL. Therefore, it is possible to speculate that a low level of PRL concentration in the SLP observed in our study is too low to maintain normal corpus luteum function.…”

mentioning

confidence: 99%

Low serum levels of FSH, LH and prolactin in luteal phase inadequacy.

Minakami¹,

Kimura²,

Tamada³

1985

Endocrinol Japon

View full text Add to dashboard Cite

In order to elucidate the relationship between prolaction (PRL) levels and corpus lutcum function in humans, assessment of temporal relationship between levels of PRL, LH, FSH, estradiol and progesterone was made in eleven normal cycling women and six short luteal women . All hormones were determined by specific radioimmunoassay.The mean PRL level in the luteal phase was higher than that in the follicular phase in normal women . On the other hand, no difference mean was seen between the PRL levels of follicular and luteal phases in short luteal women. In addition, follicular and luteal phase secretion of PRL in the short luteal phase (SLP) was lower than that in the normal control.LH and FSH in the follicular and luteal phases , estradiol secretion in the late follicular and early to mid-luteal phases in SLP were also lower than those in the control. These observations were consistent with the hypothesis that SLP is a sequel to aberrant folliculogenesis . In addition, it is inferred that low PRL levels in the SLP might be due to inadequate augmentation by estrogen, rather than giving PRL any positive controlling role in the maintenance of corpus luteum function.

show abstract

“…In an important series of studies, Richards and Midgley (10) and Richards et al (11) demonstrated that administration of estrogen and FSH to the 24-day-old hypophysectomized rat leads to a marked increase in the granulosa cell FSH receptor population; the action of estrogen and FSH in time also leads to the appearance of the LH receptor population; the process of luteinization subsequently leads to the appearance of the PRL receptor population. PRL is also present in follicular fluid, but its role in granulosa cell function is not understood at this time (12).…”

Section: Follicle Developmentmentioning

confidence: 99%

Basic mechanisms of ovarian endocrine function

Schomberg¹

1978

Environ Health Perspect

View full text Add to dashboard Cite

This review outlines the current understanding of ovarian endocrine development and regulation with both physiological and biochemical background to provide a framework applicable to problems concerning environmental agents and ovarian endocrine function. Two approaches are used. First, the endocrine regulation of foUicle development and corpus luteum function is considered in the classical sense, i.e., viewing these structures as gonadotropin-responsive units undergoing a programmed sequence of development and differentiation. Secondly, a relatively new area of ovarian physiology concerned with intra-ovarian regulation is explored, since this area holds potential for exploration of the direct effects of toxicological or environmental agents upon gonadal endocrine cells. Follicle DevelopmentGonadotropin-Independent and Dependent StagesThe stages of follicular maturation have been classified in a variety of ways by several different investigators, depending upon the degree of detail necessary (1, 2). For purposes of this discussion, distinction need only be made between the following: (1) the primordial follicle stage, characterized by an immature ovum surrounded by a single layer of flattened or disc-shaped granulosa cells; (2) the primary follicle stage, characterized by a transition in granulosa cell morphology to the cuboidal form followed by an increase in the number of granulosa cell layers (In the rat, oocyte growth is complete by the four-layer granulosa cell stage); and (3) Follicle development in most species, with the notable exception of the human (3), is thought to be independent of gonadotropic support up to the

show abstract

A possible role for prolactin in control of steroid secretion by the human Graafian follicle

Cited by 482 publications

References 12 publications

Modulation of Functional Capacity of Small Ovarian Follicles in the Post-partum Cow by Prolactin

Modulation of Functional Capacity of Small Ovarian Follicles in the Post-partum Cow by Prolactin

Low serum levels of FSH, LH and prolactin in luteal phase inadequacy.

Basic mechanisms of ovarian endocrine function

Contact Info

Product

Resources

About