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T Aono

Publications and source records attributed to T Aono.

At least 289 records · Page 16Linked to original sources
PubMed1984

Absence of effect of the peptide PHI-27 on LH release in vitro.

The effects of PHI-27, a peptide of the glucagon-secretion family, on luteinizing hormone (LH) release and on LH-releasing hormone (LH-RH)- or estradiol-induced LH release were examined in a sequential double chamber perifusion system by perifusing the pituitary alone or in sequence with the mediobasal hypothalamus (MBH) from normal female rats in diestrus. PHI at 10(-7) M had no significant effect on LH release from the pituitary in series with the MBH. Moreover, on perifusion of the pituitary alone with medium containing 10(-7) M PHI, LH release induced by 20 ng/ml LH-RH from the pituitary was not significantly different from that without PHI. Furthermore, PHI had no effect on estradiol-induced LH release from the pituitary in sequence with the MBH. These data indicate that PHI has no effect on LH release in vitro.

Animals↗
PubMed1984

Abnormality of testicular FSH receptors in infertile men.

To ascertain whether abnormalities in testicular binding of follicle stimulating hormone (FSH) are related with spermatogenic impairment found in idiopathic male infertility, we measured FSH receptors in testicular tissues obtained by biopsy from 37 infertile men. Since there had been few reports on the characterization of human testicular FSH receptor, we first established conditions for FSH receptor assay in small amounts of human testicular tissues taken by biopsy. Thirty-seven infertile men were divided into 3 groups by histological grading using Johnsen's score count, and testicular FSH receptors among these groups were compared. Although 6 of 12 infertile men with low Johnsen's score count and 3 of 9 men with middle score count had no obvious FSH binding sites with high affinity, all 16 men with high score count had high affinity FSH binding sites. The present findings demonstrate that the decrease in testicular high affinity binding sites for FSH is related with the degree of spermatogenic impairment found in idiopathic male infertility.

Adult↗
PubMed1984

Hydrocortisone elicits the effect of clomiphene citrate on luteinizing hormone-releasing hormone release in vitro.

The effect of hydrocortisone on the release of luteinizing hormone (LH) and LH-releasing hormone (LRH) in response to clomiphene citrate (clomiphene) were examined in a sequential double chamber perifusion system by perifusing the mediobasal hypothalami (MBH) and/or pituitaries excised from normal female rats in dioestrus. When the MBH and the pituitary were perifused in sequence with medium containing 5 X 10(-6) M hydrocortisone, a significant release in LH (100- 150% increase, P less than 0.01-P less than 0.05) was observed 40 min after the administration of 3 X 10(-8) mol clomiphene. Clomiphene had no effect on LH release from the pituitary when perifused in series with the MBH without basal hydrocortisone infusion. Administration of clomiphene did not cause a significant increase in LH from the pituitary perifused alone, with or without medium containing hydrocortisone. The concentration of LRH in the efflux was significantly increased 40 min after clomiphene administration when MBH was perifused with medium containing hydrocortisone, whereas clomiphene had no effect when perifused with medium only. These data indicate that hydrocortisone stimulates the effect of clomiphene on LRH release from the hypothalamus, which in turn induces LH release from the pituitary.

Animals↗
PubMed1984

Involvement of norepinephrine in pituitary LH release induced by oestradiol in vitro.

The direct effects of oestradiol-17 beta (E2) on pituitary luteinizing hormone (LH) release and the role of norepinephrine (NE) in E2-induced gonadotrophin release were examined in a sequential double chamber perifusion system by perifusing the mediobasal hypothalami (MBH) and/or pituitaries excised from normally cycling female rats. Administration of E2 induced significant release (70-160% increase, P less than 0.05) of LH from the pituitary of rats in pro-oestrus, but not in other stages of the oestrous cycle. When the MBH and the pituitary were perifused in sequence, E2 induced significant release of LH in all stages of the oestrous cycle except oestrus. When the pituitary from rats in dioestrus II was perifused alone with medium containing 200 ng/ml NE, significant release of LH (80-170% increase, P less than 0.05) was observed after the administration of E2. The E2-induced LH release in pro-oestrus was completely abolished by perifusion with medium containing diethyldithiocarbamate, an inhibitor of NE synthesis. These findings suggest that NE may be involved in changes of pituitary responsiveness in LH secretion to oestrogen during the rat oestrous cycle.

Animals↗
PubMed1984

Restoration of LH pulsatility in patients with prolactinomas after trans-sphenoidal surgery.

In hyperprolactinaemic patients with amenorrhoea, pulsatile secretion of LH is reported to be infrequent or absent. For further assessment of the effect of prolactin (Prl) on LH pulsatility, the serum gonadotrophin concentration was determined at 15 min intervals for 180 min in 12 patients with prolactinomas before treatment and in 6 patients who showed normalization of the Prl level after trans-sphenoidal surgery. Surgical treatment caused a significant reduction (P less than 0.05) of the mean (+/- SE) serum Prl level from 519 +/- 152 to 9.2 +/- 1.4 ng/ml. The mean LH level (7.3 +/- 1.2 mIU/ml) before treatment was significantly increased (P less than 0.05) after trans-sphenoidal surgery (12.7 +/- 2.4 mIU/ml). An LH spike was defined as an LH concentration that exceeded the mean LH level over the study period by 2 SD of the intra-assay variation, achieving a level of above 10 mIU/ml. LH spikes were observed in 2 of 12 patients (16.7%) before treatment, and in 5 of 6 patients (83.3%) after trans-sphenoidal surgery, the difference being significant (P less than 0.05). These results suggest that hyperprolactinaemia in prolactinoma patients may cause impaired LH pulsatile secretion and that this derangement can be reversed by reduction of the Prl level by adenomectomy.

Adenoma↗
PubMed1984

Improvement of spermatogenesis by hCG and hMG treatment in pubertal boys with history of orchiopexy at early childhood.

Twelve early-pubertal boys (12-3/12 to 14-11/12 years of age) who had received orchiopexy for bilateral cryptorchidism at 3-1/12 to 5-9/12 years of age were treated with long-term administration of hCG and hMG, 1000 IU and 150 IU, respectively, weekly during puberty. The restoration of spermatogenesis by the treatment was evaluated by measuring the mean sperm count in the seminal fluid ejaculated at late-pubertal age or after completion of puberty (16-6/12 to 18-1/12 years of age). Of the 12 patients treated with hCG and hMG, 5 showed moderate oligozoospermia (5-40 million sperm/ml), 2 showed severe oligozoospermia (less than 5 million sperm/ml), and 5 were azoospermic. Of another 11 such patients who were not treated with hCG and hMG during pubertal age, 9 patients were azoospermic and only 2 showed severe oligozoospermia. The rate of motile sperm assessed from all semen showed asthenozoospermia (20-61%). These findings suggest that gonadotropins administered during puberty may have some effects on restoration of spermatogenesis in patients who had orchiopexy for bilateral cryptorchidism in early childhood.

Adolescent↗
PubMed1984

Functional and morphological characteristics of transplantable rat pituitary tumors established in nude mice.

Two strains of transplantable rat pituitary tumors, MtT SA5 and MtT SA6, have been established in female nude mice from a single original pituitary tumor which had spontaneously occurred in a female Wistar rat at 759 days of age. MtT SA5 tumor produces prolactin (PRL), growth hormone, and adrenocorticotropic hormone, and MtT SA6 tumor secretes PRL and growth hormone. Additionally, both tumors induce severe nephropathy and promote pathogenicity of murine hepatitis virus, resulting in hepatic necrosis. Electron micrographs of MtT SA5 and MtT SA6 tumors revealed three and two types of cells, respectively, in reference to secretory granules. The tumors seem to consist of mixed population, each cell secreting each hormone. Since marked adrenal enlargement and relatively low serum corticosterone levels were found in MtT SA5-bearing rats, it is suggested that MtT SA5 tumor secretes adrenocorticotropic hormone and/or its related peptides which induce adrenal hyperplasia with little or no stimulation of corticoid production. In nude mice bearing MtT SA5 tumor, concentrations of growth hormone in serum and tumor tissue were exceedingly higher than those of PRL, while they were in the same magnitude in MtT SA6-bearing nude mice. We also found that PRL levels in serum and tumor tissue of MtT SA5-bearing nude mice were much higher in males than females, although those of MtT SA5-bearing rats were not significantly different in both sexes.

Adrenal Glands↗
PubMed1983

Annulate lamellae in prolactin-secreting pituitary adenomas.

Electron-microscopic examination revealed the presence of annulate lamellae in four of five prolactinomas. All the patients examined were 24--30-year-old women who had suffered from amenorrhea and galactorrhea for 3-5 years. Serum levels of prolactin were 114--4,700 ng/ml. The tumors removed by a transsphenoidal approach were 4-23 mm in diameter and showed the ultrastructural features of sparsely granulated prolactinoma. Analysis in correlation with clinical and laboratory data revealed that the annulate lamellae were found in rapidly growing prolactinomas. This is the fifth report on pituitary adenomas with annulate lamellae.

Adenoma↗
PubMed1983

Effects of clomiphene citrate on the pituitary gland in chronically estrogenized rat.

Effects of clomiphene citrate (clomiphene) on the pituitary gland of chronically estrogenized ovariectomized rats were investigated. Estradiol-17 beta (E2) pellet implanted subcutaneously in castrated rats for 7 days caused significant increases in pituitary weight and serum prolactin (PRL) level but suppressed serum luteinizing hormone (LH) level. In the estrogenized rats about 40% of estrogen receptor (ER) found in whole pituitary cells (65 +/- 7 fmol/10 mg tissue) was observed in the nucleus, while 60% of ER was present in the cytosol fraction. A single injection of 5 micrograms E2 translocated cytosol ER immediately to nuclear compartment; amounts of ER found in cytosol and nuclear fractions were 16 +/- 1 and 37 +/- 4 fmol/10 mg tissue, respectively, at 1 h. However, the distribution of ER returned to the pre-injection level within 4 h. In the non-estrogenized castrated rats, the nuclear retention of ER was significantly longer than that in the estrogenized rats. A single administration of 200 micrograms clomiphene in the estrogenized rats, on the other hand, increased nuclear ER gradually. Nuclear ER reached the peak level at 4 h (62 +/- 5 fmol/10 mg tissue) and the level remained almost unchanged for 24 h. Cytosol ER decreased and reached a nadir at 4 h (4.3 +/- 0.3 fmol), and the replenishment of cytosol ER could not be detected for 24 h. Similar patterns of cytosol and nuclear ER following the clomiphene injection were also found in the castrated rats. The clomiphene administration in the estrogenized rats resulted in a significant reduction of the pituitary weight 48 h after the administration. The present results seem to show the antiestrogenic action of clomiphene in the pituitary gland.

Animals↗
PubMed1983

Absence of effect of danazol on estrogen-induced luteinizing hormone release from rat hypothalamo-pituitary axis in vitro.

The effects of danazol on luteinizing hormone (LH) release by estradiol (E2) were examined in a sequential double chamber superfusion system by superfusing the mediobasal hypothalamus (MBH) and pituitary excised from normal female rats in diestrus. Administration of 3x10(-13) mole E2 caused a significant (p less than 0.05) increase of LH (80-220% above the pre-injection level) from the pituitary in series with MBH superfused with Medium 199 alone or Medium 199 containing 10(-4)M danazol. These data indicate that acute administration of danazol does not affect estrogen-induced LH release in rats.

Animals↗
PubMed1983

Congenital malformations of newborn infants after clomiphene-induced ovulation.

The effect of clomiphene citrate (CC) on the incidence of congenital malformations in newborn infants was assessed from the outcome of 1034 pregnancies after CC-induced ovulation recorded at nine university hospitals in a 5-year period. Of these pregnancies, 14.2% ended in abortion, 0.5% in ectopic pregnancy, 0.1% in molar pregnancy, and 1.6% in stillbirth. In all, 935 infants were born, and 21 (2.3%) showed visible malformations. This incidence of malformations was not significantly different from that in 30,033 infants (1.7%) after spontaneous ovulation (spontaneous ovulation group), and the types of malformations after CC treatment were similar to e those in the spontaneous ovulation group. These data indicate that CC has no teratogenic effect.

Abnormalities, Drug-Induced↗
PubMed1983

Psychophysiological studies of eating disorders by means of visual evoked responses.

The psychic conditions of 14 patients with eating disorders were examined psychophysiologically. Visual evoked potentials (VEPs) and vertex potentials (V-potentials) as visual evoked responses (VERs) were recorded simultaneously at rest and during hyperventilation. The correlation between manifest anxiety measured by the MAS test and the increased amplitudes of VERs during hyperventilation was examined. The results showed that the psychic conditions of the typical anorexia nervosa patients were similar to a state of alexithymia, as they showed less manifest anxiety. The amplitudes of the VEPs and V-potentials did not increase during hyperventilation as did those of hysteric and obsessive-compulsive neurotic patients. Psychic conditions of patients suffering from the other type of eating disorders were contrary to the former group, viz., they showed much manifest anxiety. The amplitudes of the VERs increased markedly during hyperventilation as did those of anxiety neurotic patients. Mechanisms of increased amplitudes during hyperventilation as well as the correlation between manifest anxiety and anorexia nervosa are discussed. In conclusion, we would suggest that the typical cases of anorexia nervosa can be classified as psychosomatic disease and the atypical cases and the other eating disorders as neuroses.

Adult↗
PubMed1983

Estrogen induces the release of luteinizing hormone-releasing hormone in normal cyclic women.

The plasma concentrations of immunoreactive LRH, LH, and FSH were determined by RIA every 6 h until 72 h after iv administration of conjugated estrogens during the midfollicular phase. The percentage change in LH from the preinjection level showed a biphasic pattern after the injection of conjugated estrogens, i.e. significant suppression (-70%) from 6-42 h after the injection, followed by a rebound increase with a peak (+150%) at 56 h. Plasma FSH after the injection also showed a biphasic pattern. The plasma immunoreactive LRH levels were unchanged until 32 h after the injection, but then increased significantly (P less than 0.02) to 160% of the preinjection level at 42 h and then decreased rapidly. These data indicate that 1) estrogen administration results in increases in plasma immunoreactive LRH and LH, and the peak of plasma LRH precedes that of gonadotropin; and 2) the negative feedback effect of estrogen on gonadotropin secretion may not be mediated through LRH.

Adult↗
PubMed1983

Sodium induces oxytocin release from superfused rat pituitary.

The effects of various osmotic agents on the release of oxytocin were examined in a superfusion system. Oxytocin was released significantly from the rat pituitary by superfusion with medium of an osmolality of 350 mOsm/kg H2O adjusted with NaCl, regardless of the presence of the rat hypothalamus. Media adjusted to an osmolality of 350 mOsm/kg H2O with sucrose, glucose, urea or mannitol had no effect on oxytocin release from the hypothalamo-pituitary complex. Medium containing excess Na2SO4 induced significant release of oxytocin from the pituitary without the hypothalamus. The administration of tetraethylammonium chloride had no oxytocin secretion. These data suggest that oxytocin release from the pituitary is influenced by the level of sodium ion rather than the osmotic pressure.

Animals↗
PubMed1983

Norepinephrine induces releases of both LH-RH from the hypothalamus and LH from the rat pituitary in vitro.

The effects of norepinephrine (NE) on the release of luteinizing hormone (LH) and LH-releasing hormone (LH-RH) were examined in a sequential double chamber perifusion system by perfusing the medio-basal hypothalamus (MBH) and/or pituitaries excised from normal female rats in diestrus. When the pituitary alone or in sequence with the MBH was perifused with medium containing 200 micrograms/ml of NE, the concentration of LH in the efflux was significantly (p less than 0.05) increased to the level 50-150% over the pre-injection control, whereas medium without NE had no effect. Perifusion of the pituitary in sequence with the MBH produced a higher peak level of LH than that attained by the perifusion of the pituitary alone. Administration of NE induced a significant increase in LH-RH release from the MBH, although the medium alone had no effect. These data suggest that NE induces LH release from the pituitary both by increasing LH-RH release from the MBH and by its direct action on the pituitary.

Animals↗