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N Furuhashi

Publications and source records attributed to N Furuhashi.

At least 91 records · Page 5Linked to original sources

[Galactorrhea].

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Amenorrhea↗

[Secretion and Sex differences in cord serum growth hormone levels of the human fetus (author's transl)].

Cord venous growth hormone (GH) and somatostatin levels were measured by radioimmunoassay in 86 infants and 11 anencephalic infants. 1) Cord GH levels were 69.2 +/- 20.2 ng/ml (N = 6, gestational weeks (GW) : 21-30W, mean +/- S.D.), 31.5 +/- 24.3 ng/ml (N = 11, GW : 31-36W), and 17.6 +/- 8.9 ng/ml (N = 71, GW: 37-41). In anencephalic infants, cord GH levels were significantly lower (2.3 +/- 1.4 ng/ml) than those in preterm and fullterm infants. 2) In fullterm infants, cord GH levels of small infants (19.2 +/- 9.2 ng/ml, N = 33, birth weight less than 3,250g) were significantly higher than that of large infants (15.1 +/- 8.1 ng/ml, N = 38, birth weight greater than of equal too 3,250g). On the other hands, cord somatostatin levels were relatively lower in small infants than in large infants. 3) There was a significant difference between male cord GH levels (20.6 +/- 8.9 ng/ml, N = 35) and female cord GH levels (14.6 +/- 8.0 ng/ml, N = 36). These results suggest that fetal GH secretion is suppressed by GH inhibiting factor (somatotropin release inhibiting factor) from mid gestation toward term and there is a sex difference of fetal GH secretion in fullterm fetus.

Anencephaly↗

[Prolactin releasing activity in serum of pregnant women and patients with galactorrhea-amenorrhea syndrome].

Serum samples obtained from 18 normal men and women, 24 pregnant women of the third trimester, and 8 patients with galactorrhea-amenorrhea syndrome (GAS) were subjected to a 3-phase methanol extraction. The serum extract released prolactin (PRL) specifically from rat anterior pituitary in vitro. The PRL releasing activity (PRA) was dependent on the incubation time and dose of serum extract, while independent on TRH or PRL in serum. The mean PRA in serum of pregnant women was significantly (p less than 0.02) higher than one of normal subjects. The mean PRA in serum of GAS was significantly higher than in pregnant women (p less than 0.05), and in normal subjects (p less than 0.001). When the individual PRL levels were compared to the PRA in samples from pregnant women and normal subjects, a significant (p less than 0.02) positive correlation evolved. These results indicate that a PRL releasing substance(s) distinct from TRH is (are) present in serum, and has (have) a relationship to the PRL concentration and late pregnant states.

Adult↗

[Serum gonadotropin concentrations in preterm infants and sex difference (author's transl)].

We measured FSH and LH concentrations in 130 cord sera and 217 peripheral sera obtained from infants of 28-42 weeks in gestation, aged 5-75 days after birth, by radioimmunoassay. Cord FSH and LH levels were 3.9-13.6 mIU/ml and 43.3-88.5 mIU/ml respectively, and decreased with advancing gestation. Although FSH levels in 28-31 weeks were higher in female than in male, another sex difference was not found. Postnatal FSH levels in male preterm infants decreased within 10 day, thereafter continued low levels (3.7-5.6 mIU/ml). However, in male term infants and female infants, FSH levels increased with peak levels between 11-30 days after birth, and then decreased gradually. The elevation of FSH levels in female was more remarked and prolonged in preterm infants than in term infants. Postnatal LH levels in both male and female decreased rapidly after birth, and then had similar pattern of FSH levels. Serum gonadotropin levels during the neonatal period were higher in female than in male, except for LH in term infants (male greater than female).

Female↗

[Sex differences in correlation coefficient among the cord serum levels of LH-hCG, beta-hCG, FSH, estradiol cortisol and testosterone (author's transl)].

Lutenizing hormone (LH-hCG), follicle stimulating hormone (FSH), beta-human chorionic gonadotropin (beta-hCG), estradiol, cortisol and testosterone were determined and correlated with each hormones in 62 cord sera (32 male and 35 female infants). Mean (+/- S.E.)male cord sera cortisol concentrations (36.2 +/- 3.9 ug/dl) were significantly (p less than 0.05) higher than that of female (24.1 +/- 3.7 ug/dl). Another hormones were not found significant sex difference. Regression analysis showed significant positive correlations between LH-hCG (r = 0.525, p less than 0.001) or beta-hCG (r = 0.461, p less than 0.005) levels and FSH levels in all cord sera (N = 67). In male cord sera, there were significant positive correlations between LH-hCG (r = 0.493, p less than 0.01) or beta-hCG (r = 0.485, p less than 0.01) levels and testosterone levels. There was a significant positive correlation (p less than 0.01) between estradiol levels and testosterone levels in female cord sera. These data suggest (1) the sex difference of cortisol levels which indicate the response for the stress during labor and delivery, (2) there was a significant sex difference in the maturation of the feed back mechanism in pituitary-gonadal axis.

Chorionic Gonadotropin↗

[The role and secretion of prolactin in the human fetus and neonate (author's transl)].

Prolactin (PRL), growth hormone (GH), and estradiol-17 beta (E2-17 beta) levels were measured by radioimmunoassay in umbilical venous serum from 118 full term normal infants and 11 anencephalic infants. In anencephalic infants, the concentration of GH:2.4 +/- 1.6 ng/ml (mean +/- SD, n = 11) and E2-17 beta:2.3 +/- 1.4 ng/ml (n = 6) were significantly lower than those in normal infants (GH: 16.5 +/- 9.0 ng/nl n = 65; E2-17 beta:12.4 +/- 8.0 ng/ml, n = 108). There was no significant difference of PRL levels between normal infants (324 +/- 118 ng/ml, n = 118) and anencephalic infants (253 +/- 86 ng/ml, n = 10). There was significant positive correlations between PRL and E2-17 beta levels in normal infants (p less than 0.01), and was significant negative correlation between PRL levels and birth weight (p less than 0.01). These results suggested that PRL secretion is affected by estrogens during fetal period and fetal PRL has some effects for the regulation of fetal growth as somatogenic hormone.

Anencephaly↗

Effects of synthetic LH-RH and TRH on pituitary function in anencephalic infants.

The pituitary endocrine function in 4 anencephalic infants was studied by measuring the concentrations of growth hormone, prolactin, thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in umbilical venous serum. There was no significant difference in hormone levels between the anencephalic and normal infants. The response of FSH and LH was negative after administration of 10 micrograms of luteinizing hormone-releasing hormone. The TSH levels after administration of 50 micrograms of TRH elevated about 4- to 6-fold over pre-administration levels. These results indicate that the hypothalamo-pituitary axis of the human fetus initiates its function from mid-pregnancy; TSH may have an autoregulating system of the pituitary itself.

Anencephaly↗

A role of guanosine 3',5'-monophosphate in human-prolactin-induced estrogen production by feminizing adrenal neoplastic cells.

Using feminizing adrenal neoplastic gland (FANG) cells we showed that hPRL stimulated cGMP biosynthesis. Also we could clearly demonstrate a stimulatory effect of db-cGMP plus theophylline on estrogen production without concomitant stimulation of cell growth. These findings indicate that a stimulatory effect of hPRL on estrogen biosynthesis by Fang-8 cells may act via increased cGMP concomitant with depressed cAMP.

Adrenal Gland Neoplasms↗

Sex difference in the induction of lactogenic receptors in rat livers.

The relationship between serum levels of growth hormone (rGH), prolactin (rPRL), luteinizing hormone (rLH), follicle-stimulating hormone (rFSH), corticosterone, oestrogen, (oestradiol-17 beta) and testosterone and the hepatic binding sites specific to [125I]human-prolactin (h-PRL) were investigated in normal rats, in rats bearing the GH- and PRL-secreting tumour (GH3), and in rats 14 days after tumour removal. The presence of GH3 tumour elevated serum levels of rGH and rPRL and concomitantly increased the hepatic binding of [125I]h-PRL; the male rats had a greater increase than the female rats. The increased binding was due to an increase in the specific membrane binding sites, whereas the affinity constant (Ka) was not changed. In both male and female rats, there was a significant positive correlation between ser-m rGH levels (P less than 0.001) or serum rPRL (P less than 0.02) and specific binding of [125I]h-PRL in female rats only (P less than 0.02). In male rats, there was a significant negative correlation between serum testosterone levels and specific bindings of [125I]h-PRL (P less than 0.05). These results suggest that rGH and rPRL regulates the hepatic h-PRL receptors in female rats, and testosterone predominantly inhibits the induction of the hepatic lactogenic receptors in male rats.

Animals↗

Hormone receptors in livers of GH3 tumor-bearing rats: the predominant effect of growth hormone and testosterone.

The relationship between serum levels of rat GH (rGH), rat PRL (rPRL), corticosterone, estrogen, and testosterone and the liver-binding sites specific to [125I]iodo-human GH (hGH), -human PRL (hPRL), and -rPRL were investigated in normal rats, in rats bearing the GH- and PRL-secreting tumor (GH3), and in rats 14 days after tumor removal. The GH3 tumor elevated serum levels of rGH and rPRL and concomitantly increased the hepatic binding of radioiodinated hGH, hPRL, and rPRL; male rats had a greater increase than female rats. The increased binding was due to an increase in the specific membrane-binding sites, the receptors, whereas the affinity constant of binding (Ka) was not altered. In both male and female rats, the specific binding of receptors and the total binding capacities of livers correlated positively with serum levels of rGH (P less than 0.02) and inversely with serum levels of testosterone (P less than 0.05). There was insignificant or no correlation between rPRL or other steroids and the total liver-binding capacities. These results suggested that GH was the primary inducer and testosterone was the predominant regulator of the hepatic receptors in rats. The observed sex difference in the increase of receptors by GH3 tumor indicated that in normal and tumor-removed male rats, testosterone had suppressed the induction of hepatic receptors.

Animals↗

Purification of rat prolactin releasing factor by gel filtration.

Pregnant rat hypothalamic fragments were extracted with 30 mM Tris-HCl buffer at pH 7.8, subjected to enzymatic digestion, and applied to gel filtration on Sephadex G-25 for purification of the prolactin releasing factor. Effect of the eluted fractions on the release of prolactin were tested by the determination of serum and pituitary prolactin after the injection in lactating rats. Prolactin was estimated by radioimmunoassay. One fraction (tube number 61--73) eluted later than synthetic ACTH enhanced release of prolactin 30 min after injection, but other fractions had no effect on the release of prolactin. Prolactin releasing factor would be quantitatively predominant over prolactin inhibiting factor in pregnant rat.

Animals↗