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Biomedical subjects

S Usuki

Publications and source records attributed to S Usuki.

At least 19 recordsLinked to original sources
PubMed1992

Regulation of activin beta A mRNA level by cAMP.

We demonstrated the presence of five species of the activin beta A mRNA in human placenta and one major RNA associated with two minor RNAs of the activin in the fetal membrane. We investigated the effect of 8-bromo-cAMP (8-Br-cAMP) on accumulation of activin beta A subunit mRNA in human fibrosarcoma HT1080 cells. Although low levels of the activin mRNA were detectable in the untreated cells, the one main RNA species was predominantly accumulated by 8-Br-cAMP. We propose that generation of multiple activin mRNAs in the fetal membrane and cAMP-treated HT1080 cells is presumably due to a cell-specific alternative polyadenylation.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1992

High susceptibility of analbuminemic rats to neurogenic tumor induction by transplacental administration of N-ethyl-N-nitrosourea.

The susceptibilities of Nagase analbuminemic rats (NAR) and control Sprague-Dawley rats (SDR) to N-ethyl-N-nitrosourea (ENU) were compared. In Experiment I, the rats were given daily subcutaneous injections of 10 mg/kg of ENU for a week from 4 weeks of age. In Experiment II, mother rats were given a single subcutaneous injection of 60 mg/kg of ENU on day 17 of pregnancy and tumor development in their offspring was examined. In Experiment I, the incidence of neurogenic tumors was slightly, but not significantly, higher in NAR than in control rats. In Experiment II, the incidence of total tumors including neurogenic tumors was significantly higher in NAR (40/43, 93.0%) than in SDR (13/61, 21.3%). NAR showed particularly high susceptibility to induction of neurogenic tumors (34/43, 79.1%) and renal tumors (15/43, 34.9%). In an attempt to elucidate the underlying mechanisms of the increased susceptibility of NAR to ENU, O6-ethylguanine, a major premutagenic ethylated DNA adduct, was quantitated in fetal brain DNA of NAR and SDR after a pulse exposure to 60 mg/kg ENU. No significant difference in the initial formation or subsequent repair of O6-ethylguanine was observed in the two strains, indicating that abnormality at some later stage(s) of chemical carcinogenesis may lead to the increased susceptibility of NAR to induction of neurogenic tumors.

Animals↗
PubMed1992

A proposal of ovarian ERAANPS (endothelin-renin-angiotensin-atrial natriuretic peptide system) and effects of tokishakuyakusan, keishibukuryogan, shakuyakukanzoto and unkeito on the ERAANPS.

We have previously shown the presence in a high concentration of endothelin-1 (ET) in the corpus luteum and renin-angiotensin system (RAS) and binding sites for atrial natriuretic peptide (ANP) in the ovarian follicle. The present study was undertaken to identify the existence of ET, renin, angiotensin II and the binding site for ANP in the ovary at proestrus and examine in vivo the effects of herbal medicines [Tokishakuyakusan (TS), Keishibukuryogan (KB), Shakuyakukanzoto (SK) and Unkeito (UT)] on them. ET, all components of RAS and binding sites for ANP were found at high levels in the ovary. TS, KB, SK and UT decreased the ET levels in ovary, while components of RAS and binding sites for ANP have the propensity to increase. However, ET, renin, angiotensin II and ANP levels in plasma were not at all affected before and after treatment with TS, KB, SK or UT. Taken together with previous observations showing the existence of ET, RAS and the binding site for ANP in the ovary, we propose here the ERAANPS (endothelin-renin-angiotensin-ANP system) in the ovary as a functional regulator. Further, these results suggest that TS, KB, SK or UT may regulate the ovarian ERAANPS.

Animals↗
PubMed1992

Effects of tokishakuyakusan, keishibukuryogan and unkeito on DNA polymerase alpha activity in uteri of pregnant mare's serum gonadotropin-treated immature rats.

To provide some insights how herbal medicines affect deoxyribonucleic acid (DNA) synthesis in the uterus, the DNA polymerase activities (alpha and beta) in uterine samples taken from rats were measured. DNA polymerase alpha activity with respect to DNA content revealed alpha cyclic change with the highest level on proestrus, while DNA polymerase beta activity showed no significant changes during the estrous cycle. The increased period of the activity coincided with that of 17 beta-estradiol (E2) but not progesterone (P4) in the blood. Injection of 10 IU pregnant mare serum gonadotropin (PMS) on day 27 of age gradually increased DNA polymerase alpha activity in uteri, while concomitant treatment with PMS and 200 micrograms Tokishakuyakusan (TS), Keishibukuryogan (KB) or Unkeito (UT) suppressed the enzyme activity, with a most remarkable effect of KB. These results suggest that TS, KB or UT suppresses in vivo DNA polymerase alpha activity induced by PMS in the rat uterus.

Animals↗
PubMed1992

Effects of tokishakuyakusan, keishibukuryogan, shakuyakukanzoto and unkeito on ovarian endothelin, renin and angiotensin II in pregnant mare's serum gonadotropin-treated immature rats.

We have previously proposed the ovarian ERAANPS (endothelin-rein- angiotensin-atrial natriuretic peptide system). The present study was undertaken to examine in vivo the effects of herbal medicines [Tokishakuyakusan (TS), Keishibukuryogan (KB), Shakuyakukanzoto (SK) and Unkeito (UT)] on endothelin-1 (ET), renin and angiotensin II (A II) in the ovaries, of immature rats treated with 10 IU PMS for 48 h. ET and all components of renin-angiotensin system (RAS) were found at high levels in the ovary. Concomitant treatment with PMS plus TS, KB, SK or UT, especially TS and UT, tended to decrease the ET levels in ovary, while components of RAS tended to increase. However, ET, renin and A II levels in plasma were not at all affected after treatment with TS, KB, SK or UT. These results suggest that TS, KB, SK or UT may regulate the ovarian ERAANPS.

Animals↗
PubMed1992

Effects of Tokishakuyakusan, Keishibukuryogan and Unkeito on DNA polymerase alpha activity in PMS-treated immature rat uterus incubated in vitro.

We have recently found that Tokishakuyakusan (TS), Keishibukuryogan (KB) or Unkeito (UT) inhibits in vivo DNA polymerase alpha activity in the rat uterus stimulated by PMS. In this study, uteri resected 24 h after injection of PMS on day 27 of age were incubated in vitro with 20 micrograms/ml of extract of TS, KB or UT for 4 h. The DNA polymerase alpha activity in uteri tended to decrease after the addition of TS, KB or UT with significant difference (P < 0.05) compared with TS-, KB- and UT-untreated control groups. These results suggest that TS, KB or UT, especially KB, tends to inhibit directly the enzyme activity in rat uterus.

Animals↗
PubMed1992

[Augmentation of left ventricular slow filling in hypertrophic cardiomyopathy].

To investigate the significance of augmentation of left ventricular slow filling, trans-mitral flow (TMF) was echocardiographically observed through pulsed Doppler method in 116 patients with hypertrophic cardiomyopathy (HCM), 74 with dilated cardiomyopathy (DCM), 27 with mitral regurgitation (MR), 86 with old myocardial infarction (OMI) and 80 normal controls (C). The slow filling-wave (SFW) in TMF was defined as the filling wave with obvious peak velocity during slow filling phase. The peak velocities (E, A, S) of the early filling, the atrial contraction and the slow filling waves were measured. The SFW was divided into two patterns according to the S and E ratio: large SFW (S/E greater than or equal to 1/2) and small SFW (S/E less than 1/2). 1) The small SFW was more frequently, but not significantly, observed patients with MR (37%) than in normal subjects (18%), patients with HCM (10%), DCM (4%) and OMI (7%). However large SFW was observed in 16 patients (14%) with HCM, but not in normal subjects and patients with other cardiac diseases excluding one patient with DCM. 2) In normal subjects and patients with DCM, OMI and MR, those with small SFW had larger E and smaller A/E than those without small SFW. However in patients with HCM, there was no difference in these indices (E and A/E) according to whether the patients were with or without SFW. 3) In HCM, patients with large SFW had significantly smaller E and significantly larger isovolumic relaxation time than those without SFW. Thus, appearance of the large slow filling wave, which might be caused by abnormal relaxation of the left ventricle, was frequently observed in patients with HCM.

Adult↗
PubMed1991

Endothelin-1 in luteal tissue.

The aim of this study was to immunologically and biologically detect endothelin-1 (ET-1) in rat corpora lutea (CL). Recently, we established a highly sensitive and specific sandwich-enzyme immunoassay (EIA) for ET-1. Using this assay, the presence of ET-1 was investigated in superovulated ovaries, induced with pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG), and ovaries from pseudopregnant rats, induced by cervical stimulation. A high concentration of immunoreactive endothelin-1 (ir-ET-1) was found in the CL. On reverse phase-high performance liquid chromatography (RP-HPLC) coupled with EIA, ir-ET-1 was exclusively eluted at the same position as synthetic ET-1, indicating that ir-ET-1 is identical to ET-1. The level of ir-ET-1 was significantly (P less than 0.001) higher in the CL 7 days after hCG injection than it was 4 days after hCG injection. On day 7 of pseudopregnancy (PSP), the ir-ET-1 level was also significantly (P less than 0.001) higher than on day 4 of PSP. These results demonstrated that ET-1 is present in a high concentration in the CL, suggesting a new intraovarian peptide which may have a physiological function in the ovary and which may vary in quantity according to the age of the CL.

Adsorption↗
PubMed1991

Endothelin-1 and endothelin-3 stimulate ovarian steroidogenesis.

The possible direct involvement of endothelin (ET) in preovulatory follicular steroidogenesis was investigated in vitro. Follicular development in immature rats was induced by pregnant mare's serum gonadotropin (PMS). Twenty-four and 48 h after PMS injection, ovarian follicles were incubated in vitro with or without 4 x 10(-11) to 4 x 10(-5) M endothelin-1 (ET-1) or endothelin-3 (ET-3) for 2 h, or perifused in vitro with 4 x 10(-7) M of ET-1 or ET-3 for 3 h. In the incubation study, ET-1 and ET-3 significantly stimulated progesterone, testosterone, and 17 beta-estradiol production by follicles 24 and 48 h after PMS injection. Progesterone, testosterone, and 17 beta-estradiol were increased in a dose-dependent manner by 4 x 10(-11) to 4 x 10(-6) M ET-1 or ET-3; in the case of ET-3, this increase occurred only at 24 h after PMS injection. In addition, ET-1 stimulated ovarian steroid production more effectively than ET-3. In addition to their effects on ovarian steroidogenesis, both ET-1 and ET-3 increased tissue cyclic adenosine-3',5'-monophosphate (cyclic AMP) production. The steroidogenic effect of ET-1 or ET-3 was most pronounced by follicles 48 h after PMS injection. In the perifusion experiment, ET-1 and ET-3 also stimulated progesterone, testosterone, and 17 beta-estradiol secretion. These indicate the involvement of ET-1 or ET-3 in the regulation of ovarian differentiation by stimulating steroidogenesis, at least partially through the mediation of cyclic AMP.

Animals↗
PubMed1991

Comparison of endothelin-1 concentrations in normal and complicated pregnancies.

Endothelin-1 (ET-1) may be important in regulating vascular tone in humans. To understand the role of ET-1 during pregnancy, we measured the concentrations of plasma immunoreactive ET-1 in normal, toxemic (pre-eclamptic or eclamptic), and other complicated pregnancies. There were no significant differences between ET-1 concentrations in normal pregnancy and those in toxemic pregnancy, except in one case with IgA nephropathy and severe toxemia. There also was no significant difference between the ET-1 concentrations in pure toxemia of pregnancy compared with superimposed toxemia of pregnancy. Furthermore, there was no correlation between ET-1 concentrations, blood pressure, or renal function during toxemic pregnancy. Similarly, there were no significant differences between ET-1 plasma levels in normal pregnancies and other complicated pregnancies except for two cases in which much blood was lost due to uterine atony and abruptio placenta. Thus, plasma ET-1 concentrations showed no significant relationship to blood pressure or renal function during normal or toxemic pregnancy, and were not related to the type (pure or superimposed type), grade, or severity of toxemic pregnancy.

Adult↗
PubMed1991

Effects of herbal components of tokishakuyakusan on progesterone secretion by corpus luteum in vitro.

Twenty-seven-day old female rats received 20 IU PMS and 56 hours later, 40 IU hCG. Seven days after hCG treatment, the resected ovaries were incubated in vitro with herbal components of Tokishakuyakusan (TS). Mixture of hoelen + peony root + alisma rhizone + Japanese angelica root or hoelen + Japanese angelica root or Japanese angelica root + cnidium rhizome significantly increased progesterone secretion, and these levels tended to exceed the level by TS alone. These results suggest an exquisitely blended effect of herbal components of TS on progesterone secretion by corpora lutea.

Animals↗
PubMed1991

Blended effects of herbal components of tokishakuyakusan on somatomedin C/insulin-like growth factor 1 level in rat corpus luteum.

The effect of herbal components of Tokishakuyakusan on somatomedin C/insulin-like growth factor I (IGF-1) level in medium from rat corpora lutea incubated in vitro was examined. Hoelen + poeny root + Japanese angelica root, hoelen + peony root, hoelen + Japanese angelica root or peony root + Japanese angelica root decreased the IGF-1 level. The data suggest that constituent herbal components of Tokishakuyakusan regulate the IGF-1 level by rat corpora lutea.

Animals↗
PubMed1991

Effects of hachimijiogan, tokishakuyakusan, keishibukuryogan, ninjinto and unkeito on estrogen and progesterone secretion in preovulatory follicles incubated in vitro.

Ovarian follicles, removed from 10-week old rats at 1630 hours diestrus-2, 1100 and 2300 hours proestrus, were incubated for 120 minutes with various doses of Hachimijiogan (HJ), Tokishakuyakusan (TS), Keishibukuryogan (KB), Ninjinto (NT) and Unkeito (UT). The estradiol-17 beta (E2) and progesterone concentrations in the incubation medium were measured. The concentrations of E2 were significantly decreased with TS and KB by growing follicles and with HJ, TS and KB by preovulatory follicles before a LH surge. In contrast, the levels of progesterone were significantly increased with HJ, TS, KB and UT by preovulatory follicles before a LH surge. These results suggest that HJ, TS, KB or UT stimulates preovulatory follicles before a LH surge to secrete progesterone, but TS or KB suppresses E2 secretion by growing preovulatory follicles before a LH surge.

Animals↗
PubMed1991

Successful treatment of a hyperprolactinemic infertile woman with a pituitary microadenoma using hachimijiogan.

A hyperprolactinemic infertile woman with a pituitary microadenoma, who was resistant to bromocriptine as a method of bringing on pregnancy, succeeded in having a normal pregnancy and delivery with Hachimi-jio-gan treatment. This paper reports that the patient did not succeed in pregnancy in spite of 16 months of bromocriptine treatment, though her prolactin level gradually decreased and continued to be between 40-60 ng/ml with Hachimi-jio-gan treatment. Although the level of prolactin of the patient did not normalize, she, nevertheless, succeeded in having a normal pregnancy and delivery.

Adenoma↗
PubMed1991

Tokishakuyakusan stimulates progesterone and estradiol-17 beta production by rat granulosa cells and progesterone, testosterone and estradiol-17 beta by the residual portion of the follicle in vitro.

To examine the possible effects of Tokishakuyakusan (TS) on steroidogenesis by preovulatory follicles at the cell level, the expressed granulosa cells and remaining portion of follicles from pregnant mare's serum gonadotropin (PMS)-treated immature rats were incubated in vitro with increasing concentrations of TS for 3 h. TS significantly stimulated progesterone and estradiol-17 b production, with a predominant stimulation of progesterone, by the expressed granulosa cells, while testosterone production was not stimulated. In the remaining portion of the follicle, TS also significantly stimulated progesterone, testosterone and estradiol-17 b production. Similar to the effect produced by granulosa cells, the stimulatory effect of TS was stronger on progesterone than on testosterone and estradiol-17 b production. These results suggest that TS has a potent, direct stimulatory effect on steroidogenesis, especially progesterone production, by constituent tissue compartments of rat preovulatory follicles in vitro.

Animals↗
PubMed1991

The direct luteotropic effect of tokishakuyakusan in rats.

The effect of Tokishakuyakusan (TS) on the corpus luteum function in pseudopregnant rats was examined in vivo. On day 4 of pseudopregnancy (PSP), induced by cervical stimulation, TS (20 micrograms) stimulated the progesterone secretion rate (PSR) in the ovarian venous plasma. There was also a significant increase in the rate of progesterone to 20 alpha-OH-progesterone. However, on day 8 of PSP, there was no apparent change in PSR in the ovarian venous plasma after the administration of TS. These data suggest that the sensitivity to TS of the corpus luteum varies according to its age.

20-alpha-Dihydroprogesterone↗
PubMed1991

Effects of hachimijiogan on dopamine, serotonin and vasoactive intestinal peptide in plasma and hypothalamus in sulpiride-induced hyperprolactinemic rats.

Effect of Hachimijiogan (HJ) on dopamine (DA), serotonin (5-HT) and vasoactive intestinal peptide (VIP) was examined in plasma and hypothalamic tissue of sulpiride-induced hyperprolactinemic rats (SHR). Similar to bromocriptine (BR), HJ, in combination with sulpiride, suppressed plasma prolactin levels raised by sulpiride alone. Furthermore, HJ, together with sulpiride, increased plasma DA levels decreased by sulpiride alone, while 5-HT in plasma was increased by sulpiride and HJ, individually or in combination. However, plasma VIP levels were under detection limits on some occasions after HJ treatment. Successively, DA, 5-HT and VIP levels in the hypothalamus were determined. Similar to the effect caused by BR, DA and 5-HT levels in hypothalamic tissue reduced by sulpiride alone were also significantly increased by HJ together with sulpiride, while VIP levels were sometimes under detection levels with or without HJ. These results suggest that HJ stimulates the hypothalamus to increase DA and 5-HT in SHR, providing evidence for the clinical efficiency of HJ in combating hyperprolactinemia. The effect of HJ on VIP in plasma or hypothalamic tissue is, however, questionable.

Animals↗