Times of appearance of LH and FSH activities in human fetal circulation

Levina, S. E.

doi:10.1016/0016-6480(72)90102-5

Cited by 26 publications

(13 citation statements)

References 9 publications

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“…Recent experiments with pituitary cultures confirm this finding (Siler-Khodr et al, 1974), and have also demonstrated that secretion of gonadotrophins begins earlier in females than in males. This supports earlier biological data reported by Levina (1968Levina ( , 1972 that the secretion of FSH begins 6 weeks earlier in the female than the male, and that plasma concentrations of FSH are higher in the female; these differences however are not so marked with LH.…”

Section: Gonadal F U N C T I O N I N T H E Fetussupporting

confidence: 81%

Hypothalamic‐pituitary‐gonadal Relationships in Man From Birth to Puberty

Forest

Peretti

Bertrand

1976

Clinical Endocrinology

134

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Gonadal function depends upon activities at various levels. Thus there is: (a) a central level (extra-hypothalamic, hypothalamic, and anterior pituitary); (b) an intermediate level (gonadal and plasma), and (c) a peripheral level consisting of the target organs to which the hormonal message is directed. These determine both the expression of gonadal function (physical, physiological, or psychological) and the feedback regulation of the secretion of gonadotrophins.(a) Central level (i) Extra-hypothalamic centres. The production of LH releasing hormone (LHRH) is affected in the rat, and probably in primates as well, by extra-hypothalamic stimuli coming, in particular, from the amygdala and the hippocampus. Adrenergic regulation exists at this level, noradrenaline having a stimulatory and dopamine an inhibitory effect (Bliss et al., 1972).(ii) Hypothalamic centres. These are localized in particular in the pre-optic area. Immunochemical techniques have demonstrated that LHRH is secreted by neurones of the arcuate nucleus, and released into the capillary plexus proximal to the hypophyseal portal system at the level of the median eminence, thereby reaching the anterior pituitary (Barry & Dubois, 1974;Setalo et al., 1975).(iii) Gonadotrophin secreting cells of the anterior pituitary. These synthesize and secrete the gonadotrophins, LH and FSH, under the influence of LHRH (Schally et al., 1972). The pituitary gonadotrophins stimulate the synthesis and the secretion of the gonadal

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Section: Gonadal F U N C T I O N I N T H E Fetussupporting

confidence: 81%

Hypothalamic‐pituitary‐gonadal Relationships in Man From Birth to Puberty

Forest

Peretti

Bertrand

1976

Clinical Endocrinology

134

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“…Groom et al (1971) using an in-vitro system have shown that the human foetal pituitary is capable of producing LH after the 14th week of gestation, although Levina (1972) was unable to find significant concentrations of LH in the serum of human foetuses before the 18th week. It may well be, therefore, that LH levels rise too late to account for the high values of androgens produced.…”

Section: Discussionmentioning

confidence: 95%

Effect of Human Chorionic Gonadotrophin on Testosterone Secretion by the Foetal Human Testis in Organ Culture

Abramovich¹,

Baker²,

Neal³

1974

Journal of Endocrinology

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Foetal human testes (12-22 weeks gestation), maintained in organ culture, were treated with human chorionic gonadotrophin (HCG) and the amount of testosterone produced compared with control cultures. In all cases the testes produced testosterone, but from the 13th to 18th week of gestation significantly more testosterone was produced by, and the Leydig cell hyperplasia was maintained in, the HCG stimulated organ cultures. It is suggested that HCG is ultimately responsible for differentiation of the human male external genitalia.

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“…This has been established by experiments in which foetal decapitation, castration or adrenalectomy resulted in under-development of the corresponding foetal target tissues (Jost, 1953). This has also been shown directly by hormone determination in the foetal glands and blood (Kaplan, Grumbach & Shepard, 1969;Levina, 1968Levina, , 1972Levina, , 1974. However, knowledge of the role of the foetal hormones and their target tissues is scanty.…”

Section: Introductionmentioning

confidence: 86%

Responsiveness of the Ovary to Gonadotrophins in Pre- And Perinatal Life: Oestrogen Secretion in Tissue and Organ Cultures

Levina¹,

Gyévai²,

Horvath³

1975

Journal of Endocrinology

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Secretion of oestrogen by the ovaries of foetal (15-19 days of gestation) and newborn rats in organ and tissue culture was not detectable by fluorometry when the ovary was taken from foetuses before folliculogenesis had occurred. In organ cultures of ovaries, the time of folliculogenesis corresponded with the normal timing of folliculogenesis in vivo. In tissue cultures the process of formation of follicles was delayed. Oestrogens were present in the medium when folliculogensis was fully established in the cultured foetal ovaries. Secretion began spontaneously and did nto depend on the addition of gonadotrophins to the medium. The addition of gonadotrophins the the culture medium did not effect the level of oestrogen secreted by the foetal and newborn rat ovaries during the period of incubation (2-3 weeks).

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Times of appearance of LH and FSH activities in human fetal circulation

Cited by 26 publications

References 9 publications

Hypothalamic‐pituitary‐gonadal Relationships in Man From Birth to Puberty

Hypothalamic‐pituitary‐gonadal Relationships in Man From Birth to Puberty

Effect of Human Chorionic Gonadotrophin on Testosterone Secretion by the Foetal Human Testis in Organ Culture

Responsiveness of the Ovary to Gonadotrophins in Pre- And Perinatal Life: Oestrogen Secretion in Tissue and Organ Cultures

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