Endocrine features in development of human hypothalamus, hypophysis, and placenta

Levina, S. E.

doi:10.1016/0016-6480(68)90116-0

Cited by 78 publications

(32 citation statements)

References 5 publications

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“…These observations confirm earlier studies of Levina (13), who reported an increase in PRL biological activity of fetal pituitary glands between 18-40 wk of gestation. Further, Pasteels, and coworkers (14) The pattern of change in the concentration of fetal serum PRL during gestation correlates overall with the increase in pituitary PRL content.…”

Section: Ontogenesis Of Human Fetal Hormones 159supporting

confidence: 92%

“…The mean content of PRL in the pituitary gland increased sharply from 14.8±4.6 ng at 15-19 wk to 405±142 ng at 20-24 wk and 542±204 ng at 25-29 wk gestation. By term, the mean content was 2,039± 459 (range 493-3,689) and the mean concentration 15.9±2.4 ng/mg (range [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. There was a significant positive correlation (P < 0.001) between the hPRL and human growth hormone (hGH) content of fetal pituitary glands; at term the hPRL/hGH ratio was 1/290.…”

mentioning

confidence: 99%

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The ontogenesis of human fetal hormones. III. Prolactin.

Aubert¹,

Grumbach²,

Kaplan³

1975

J. Clin. Invest.

113

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A B S T R A C T The synthesis and release of human prolactin (hPRL) in the human fetus was assessed by radioimmunoassay analysis of the content and concentration of hPRL in 82 pituitary glands and the concentration of serum hPRL in 47 fetuses of gestational age 68 days to term. Fetal hPRL exhibited parallelism with the reference standard (Lewis 203-1). hPRL was detected by 68 days of gestation (10 wk), the earliest fetal pituitary gland studied; 8 out of 33 pituitaries had a prolactin (PRL) content above 2.0 ng between 10-15 wk gestation. The mean content of PRL in the pituitary gland increased sharply from 14.8±4.6 ng at 15-19 wk to 405±142 ng at 20-24 wk and 542±204 ng at 25-29 wk gestation. By term, the mean content was 2,039± 459 (range 493-3,689) and the mean concentration 15.9±2.4 ng/mg (range 7-20). There was a significant positive correlation (P < 0.001) between the hPRL and human growth hormone (hGH) content of fetal pituitary glands; at term the hPRL/hGH ratio was 1/290. The concentration of serum hPRL between 12 and 24 wk ranged from 2.9 to 67 ng/ml, mean 19.5±2.5 ng/ml (n = 41); by 26 wk fetal serum hPRL increased sharply and attained levels of 300-500 ng/ml in late gestation. At delivery, the mean plasma concentration of hPRL was 167±+14.2 ng/ml in 36 umbilical venous specimens and 111.8±12.3 ng/ml in the matched maternal venous specimens. No correlation between serum hPRL and the pituitary content or concentration of hPRL was demonstrable in 12 matched fetal specimens.In five anencephalic infants, umbilical venous hPRL levels were between 65 and 283 ng/ml. In two anencephalic infants, thyrotropin releasing factor (TRF) (200 Ag IV) evoked a rise in serum hPRL in one patient from 43 to 156 ng/ml at 30 min, and in the other from 65 to Dr. Aubert is recipient of a grant from the Swiss National Fund for Scientific Research.

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Section: Ontogenesis Of Human Fetal Hormones 159supporting

confidence: 92%

mentioning

confidence: 99%

The ontogenesis of human fetal hormones. III. Prolactin.

Aubert¹,

Grumbach²,

Kaplan³

1975

J. Clin. Invest.

113

View full text Add to dashboard Cite

show abstract

“…In the human fetal pituitary, AVP has been identified as early as 11 wk of gestation (24,33). In other mammalian species, including the guinea pig, rabbit, sheep, and seal, the presence of AVP has been documented in the fetal pituitary gland during the last half of gestation (3,7,16,37).…”

Section: Discussionmentioning

confidence: 99%

The Dynamics of Vasopressin Release and Blood Volume Regulation During Fetal Hemorrhage in the Lamb Fetus

et al. 1979

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SummaryExperiments were performed on 11 long-term fetal lamb preparations (103-138 days of gestation) to investigate the sensitivity and relative responsiveness of the fetal volume receptors in modulating fetal plasma arginine vasopressin (pAVP) secretion and plasma renin activity (PRA) secretion during fetal hypovolemia and after fetal blood volume replacement. During fetal hemorrhage there were significant decreases (P < 0.05) in fetal hematocrit (34.7 f 2.58 to 27.0 f 1.64%), plasma proteins (3.14 f 0.15 to 2.78 f 0.19 g/100 ml), mean arterial blood pressure (MABP) (58.1 f 2.59 to 52.2 f 2.60 mmHg) and fetal arterial pH (7.38 f 0.01 to 7.35 f 0.01). A significant increase in fetal pAVP concentration from 0.73 f 0.21 to 34.9 f 10.04 pU/ml ( P < 0.01) and fetal PRA from 4.78 2.22 to 40.4 f 18.31 ng/ml/hr ( P < 0.05) was demonstrated at the peak of fetal hemorrhage. Two hr after correction of the fetoplacental blood volume, these values were back to base line levels. No change in either maternal pAVP or PRA was seen during fetal hemorrhage. When individual values for log pAVP and log PRA were plotted as a function of percent of fetoplacental blood volume removed the correlation coefficients were 0.82 and 0.60, respectively. A multiple regression analysis showed a high correlation of log pAVP and log PRA with the volume of blood removed and a low partial correlation with the fetal MABP. This suggests the decrease in fetal MABP was not the primary factor explaining the increase in pAVP and PRA during fetoplacental blood volume depletion. The data indicate that the fetal volume receptors for control of arginine vasopressin secretion are fullv functional in the last trimester of gestation and suggests that fetal pAVP and PRA are released as a; exponential function of the wrcent of feto~lacental blood volume de~letion. Finally, an isosmotic water shift from the fetal interstitial space to the fetal vascular space is described during fetal hemorrhage. SpeculationIt is suggested that a change in the equilibrium between the forces regulating fluid movement through the fetal capillary membranes, in accordance with Starling's principle, activates isosmotic water fluxes from the fetal interstitial space to the fetal vascular compartment counteracting the effects of fetal blood volume depletion. Therefore, the role of arginine vasopressin (AVP) release during fetal hemorrhage, if any, will be to act as a pressor substance helping to maintain fetal blood pressure. No major effect of AVP on placental membranes was demonstrated in vivo.Available information suggests that the newborn is capable of secreting vasopressin at birth and that both the osmoreceptors and volume control systems are fully functional (14,21,22).During fetal life, the increase in concentration of circulating vasopressin has been evoked by either osmolar or volume stimuli, using short-term fetal lamb preparations (exteriorized fetuses) (3, 32). However, the effects of surgical stress and anesthesia on the fetus may themselves have influenced this response (...

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“…Data regarding fetal vasopressin physiology, however, are meager. Vasopressin has been identified in the human fetal pituitary at 10-12 weeks of gestation (9,12) and in the fetal pituitary of other mammalian species, including the guinea pig, sheep, and seal, during the last half of gestation (1,2,10,12,14). In addition, in the sheep and monkey, significant concentrations of circulating vasopressin have been detectable in fetal blood during the last half of gestation (1, 1 l ) , and increases in circulating levels have been evoked either by osmolar or volume (hemorrhage) stimuli (1,11).…”

Section: Speculationmentioning

confidence: 99%

“…Mothers with eclampsia treated with betamethasone have increased antenatal mortality compared with controls (13); animal studies indicate that corticosteroids may compromise placental function (23) and also cause temporary inhibition of lung growth (5,11). In addition, glucocorticoid administration may be hccompanied by reduced cell numbers in the brain and by disturbances of myelination, synaptic growth, and locomotor ability (9,19).…”

Section: Speculationmentioning

confidence: 99%

Arginine Vasopressin Response to an Osmotic Stimulus in the Fetal Sheep

et al. 1978

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Summary MATERIALS AND METHODSBaseline plasma osmolality (pOsm) and plasma arginiie vasopressin (pAVP) were measured in chronically catheterized fetal sheep. Mean baseline pAVP in fetuses from 101-120 days was 1.9 + 0.46 pU/ml (mean * SEM) with a pOsm of 293 rt 1.8 mOsm/kg. In fetuses of 121-141 days of gestation, mean pAVP was significantly lower, 0.77 0.19 pU/ml (P < 0.05), with a similar pOsm (293 2 1.9 mOsm/kg). The logarithmic baseline pAVP values were linearly correlated with pOsm for both groups. Hypertonic saline infusion resulted in a similar increase in the log pAVP corrected for the rise in pOsm in the 101-120-day fetuses and in 121-141-day fetuses. The slope of this response was similar to that of the steady state relationship. The data indicates that the fetal osmoreceptor system for control of arginine vasopressin secretion is fully functional in the last trimester of pregnancy. SpeculationThe fetal hypothalamic posterior pituitary system appears to show a relatively heightened response to increases in plasma osmolality during the last trimester of gestation. This may reflect the heightened hypothalamic activity postulated to explain the high circulating growth hormone levels at this time. The higher baseline plasma vasopressin levels in the younger fetuses would support this view. Alternatively, the augmented responsiveness may represent an adaptive response to the immaturity of the fetal kidney with respect to free water clearance or an adaptive response to some extrarenal function of the hormone on salt and water homeostasis in utero.Vasopressin secretion is regulated by two systems of r e c e p tors: the osmoreceptors located in or near the supraoptic nuclei in the hypothalamus and a series of volume receptors, including left atrial stretch receptors and carotid sinus and aortic arch baroreceptors. Available information suggests that the newborn is capable of secreting vasopressin at birth and that both the osmoreceptor and volume control systems are functional (3-6). Data regarding fetal vasopressin physiology, however, are meager. Vasopressin has been identified in the human fetal pituitary at 10-12 weeks of gestation (9, 12) and in the fetal pituitary of other mammalian species, including the guinea pig, sheep, and seal, during the last half of gestation (1,2,10,12,14). In addition, in the sheep and monkey, significant concentrations of circulating vasopressin have been detectable in fetal blood during the last half of gestation (1, 1 l ) , and increases in circulating levels have been evoked either by osmolar or volume (hemorrhage) stimuli (1, 11). However, little is known about the sensitivity and relative responsiveness of the fetal osmoreceptor control system. The present studies were designed to provide this information. 5Pregnant Columbia or Columbia-Suffolk ewes were obtained from a local source and the gestational age based on the induced ovulation technique (7). The animals were maintained in the vivarium and fasted 4 8 hr before surgery. The pregnant ewes were anesthetized using a m...

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Endocrine features in development of human hypothalamus, hypophysis, and placenta

Cited by 78 publications

References 5 publications

The ontogenesis of human fetal hormones. III. Prolactin.

The ontogenesis of human fetal hormones. III. Prolactin.

The Dynamics of Vasopressin Release and Blood Volume Regulation During Fetal Hemorrhage in the Lamb Fetus

Arginine Vasopressin Response to an Osmotic Stimulus in the Fetal Sheep

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