• Korean Journal of Ichthyology
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• v.12 no.1
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• pp.71-84
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• 2000

Annual reproductive cycle of the file fish, Thamnaconus modestus (Gunther), was histologically investigated. Samples were collected monthly in the coastal waters of Chungmun, south of Cheju Island, Korea from July 1997 to June 1999. In males and females of T. modestus GSI values reached the maximum in June and May, respectively. Reproductive cycle could be divided into the following successive stages: in females, growing stage (March to April), mature stage (April to May), spawning stage (May to June), degenerative and resting stage (July to February), and in males, growing stage (January to March), mature stage (April to May), spent stage (May to June), degenerative and resting stage (July to December), respectively. To clarify the spawning cycle of female in T. modestus, some were examined, that is, the weekly changes of GSI, detail developmental stages in the ovary and the weekly changes of sex steroid hormones ($E_2$ and T) levels in plasma during the spawning period. Throughout histological observation of the ovary during the spawning period, T. modestus belonged to an asynchronous and multiple spawner. Changes of plasma $E_2$ and T levels were similar to the changes of GSI and ovary maturity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.5
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• pp.309-315
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• 2005

Changes of sex steroid hormones in the plasma of yellowfin goby, Acanthogobius flavimanus were investigated in relation to the gonadosomatic index (GSI), the hepatosomatic index (HSI) and gonadal development. The GSI in females rose rapidly in November and remained high from December to May $(7.26\pm0.89­6.62\pm0.02)$. The Male's GSI also increased gradually from November and was highest in May $(0.16\pm0.08)$. The HSI in both sexes was in reverse correlation with the GSI, and the HSI was low during the spawning season (February-May). In females, the $estradiol-17{\beta}\;(E_2)$ level increased during vitellogenesis (November and December) and reached its maximum $(8.13\pm2.87 ng/mL)$ at the maturing period, in January. $17{\alpha},\;20{\beta}$-dihydroxy-4-pregnen-3-one$(17{\alpha}20{\beta}OHP)$ gradually increased from October $(0.063{\pm}0.02ng/mL)$ to March $(0.16{\pm}0.02ng/mL)$ and increased rapidly in May. The level of testosterone (T) showed a similar tendency of $E_2$. In males, T increased gradually during spermatogenesis from September to December $(0.14{\pm}0.06­0.26{\pm}0.10ng/mL)$ and peaked in January $(0.36{\pm}0.29 ng/mL)$ when the spermatozoa filled the testis. 11-KT also rose markedly in January and then decreased. On the other hand, $17{\alpha}29{\beta}OHP$ in males did not show any clear tendencies.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.70-74
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• 1985

Serum levels of LH, FSH, prolactin, estradiol-$17{\beta}$ and progesterone were investigated every 20 days after the day of mating for the period of 140 days, at the day of parturition and thereafter 10 th and 20th day postpartum in Korean native goats. Serum levels of LH were highest with 1.95 mIU/ml at the 60 days after gestation, but maintained high levels until 100 days after gestation, and thereafter decreased gradually to 0.02 mIU/ml at the day of parturition. Prolactin concentrations increased from the 140 days after gestation, and showed highest levels with 29.75 ng/ml at the day of parturition, then decreased gradually. FSH levels determined were below 1.25 mIU/ml during the experimental period. Estradiol-$17{\beta}$ concentrations increased gradually from 7.51 pg/ml at the 20 days after gestation to 159.62 pg/ml at the day of parturition, and decreased rapidly after parturition. Progesterone levels were highest with 6.62 ng/ml at the 120 days after gestation, the decreased rapidly to 1.25 ng/ml at the day of parturition.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.715-731
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• 2021

BACKGROUND/OBJECTIVES: Premenstrual syndrome (PMS) is a disorder characterized by repeated emotional, behavioral, and physical symptoms before menstruation, and the exact cause and mechanism are uncertain. Hyperprolactinemia interferes with the normal production of estrogen and progesterone, leading to PMS symptoms. Thus, we judged that the inhibition of prolactin hypersecretion could mitigate PMS symptoms. MATERIALS/METHODS: Hordeum vulgare L. extract (HVE), Chrysanthemum zawadskii var. latilobum extract (CZE), and Lomens-P0 the mixture of these extracts were tested in subsequent experiments. The effect of extracts on prolactin secretion at the in vitro level was measured in GH3 cells. Nitric oxide and pro-inflammatory mediator expression were measured in RAW 264.7 cells to confirm the anti-inflammatory effect. Also, the hyperprolactinemic Institute for Cancer Research (ICR) mice model was used to measure extract effects on prolactin and hormone secretion and uterine inflammation. RESULTS: Anti-inflammatory effects of and prolactin secretion suppress by HVE and CZE were confirmed through in vitro experiments (P < 0.05). Treatment with Lomens-P0 inhibited prolactin secretion (P < 0.05) and restored normal sex hormone secretion in the hyperprolactinemia mice model. In addition, extracts significantly inhibited the expression of pro-inflammatory biomarkers, including interleukin-1𝛽, and -6, tumor necrosis factor-𝛼, inducible nitric oxide synthase, and cyclooxygenase-2 (P < 0.01). We used high-performance liquid chromatography analyses to identify tricin and chlorogenic acid as the respective components of HVE and CZE that inhibit prolactin secretion. The Lomens-P0, which includes tricin and chlorogenic acid, is expected to be effective in improving PMS symptoms in the human body. CONCLUSIONS: The Lomens-P0 suppressed the prolactin secretion in hyperprolactinemia mice, normalized the sex hormone imbalance, and significantly suppressed the expression of inflammatory markers in uterine tissue. This study suggests that Lomens-P0 may have the potential to prevent or remedy materials to PMS symptoms.

• Journal of Life Science
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• v.31 no.3
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• pp.314-320
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• 2021

In the present study, we investigated the effect of photoperiod and water temperature on the gonadosomatic index (GSI), histological stage of the testes, and plasma levels of sex steroid (testosterone, T; 11-ketotestosterone, 11-KT) hormones in cultured male small yellow croakers (Larimichthys polyactis). In a photoperiod experiment, small yellow croakers were reared under a natural photoperiod (NP, 10L:14D-11L:13D), long photoperiod (LP, 14L:10D), and short photoperiod (SP, 10L:14D) at 17℃ for 90 days. The GSI was significantly higher in the LP group than in the other groups at 30 and 60 days. The plasma 11-KT levels were significantly higher in the LP group than in the other groups at 30 days. In a water temperature experiment, small yellow croakers were reared under natural water temperature (NT, 19.1-15.0℃), or at 17℃, 21℃, or 25℃ under a LP (14L:10D) for 60 days. The GSI was significantly lower for the 25℃ group than for the other groups at 30 and 60 days. The plasma 11-KT levels were significantly lower for the 25℃ group than for the other groups at 60 days. Therefore, the sexual maturation of cultured male yellow croakers was promoted by LP and inhibited at water temperatures above 25℃. These findings suggest that the sexual maturation of cultured male small yellow croakers is controlled by both the photoperiod and the water temperature.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.143-147
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• 2005

Purpose : The aim of the this study was to evaluate the effect of various perinatal conditions on TSH and thyroid hormone levels in cord blood. Methods : Cord blood samples were collected from 130 neonates immediately after birth. TSH, $T_3$, and free $T_4$ levels were measured by the radioimmunoassay(RIA) method. The effects of gestational age, sex, birth weight, delivery method, perinatal asphyxia, maternal diabetes mellitus(DM), and preeclampsia on TSH and thyroid hormone levels were assessed by ANOVA test, Student t-test, and multiple regression analysis. Results : Birth weight and sex did not affect TSH and thyroid hormone levels. TSH level increased according to gestational age(P<0.05). TSH level was $4.42{\pm}0.66{\mu}IU/mL$ in infants born vaginally, which was higher than that of cesarian section delivery($3.31{\pm}0.33{\mu}IU/mL$)(P<0.05). TSH level was $5.18{\pm}0.93{\mu}IU/mL$ in asphyxiated newborns and $2.97{\pm}0.84{\mu}IU/mL$ in non-asphyxiated newborns(P<0.05). TSH level in infants with maternal DM($8.911{\pm}1.25{\mu}IU/mL$) was higher than that of infants without maternal DM($4.32{\pm}0.42{\mu}IU/mL$)(P<0.05). TSH level was $5.28{\pm}0.42{\mu}IU/mL$ in infants with maternal preeclampsia and $3.65{\pm}0.46{\mu}IU/mL$ in infants without maternal preeclampsia(P<0.05). Thyroid hormones were lower in infants with perinatal asphyxia(P<0.05). In asphyxiated infants, $T_3$ level was $75.33{\pm}55.65ng/mL$ and free $T_4$ was $0.54{\pm}0.21ng/mL$. $T_3$ and free $T_4$ level was $109.85{\pm}41.77ng/mL$ and $0.76{\pm}0.22ng/mL$ each in infants without perinatal asphyxia. Among the perinatal factors, gestational age, 1 min Apgar score and maternal DM influenced TSH level independently. Conclusion : In our study, cord blood TSH and thyroid hormone levels were affected by perinatal stress events.

• Journal of Aquaculture
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• v.22 no.1
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• pp.23-27
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• 2009

To understand the steroidogenic activities and plasma vitellogenin (VTG) profiles according to the reproductive phases in the oblong rockfish Sebastes oblongus, we examined changes in sex steroid hormones and plasma vitellogenin. Plasma levels of testosterone (T) was significantly higher value in only ovulation stage (P<0.05). In vitellogenesis, plasma estradiol-$17{\beta}$ ($E_2$) had a high level in August which was a similar higher level until ovulation than other ovarian development stages (P<0.05). However, $E_2$ was significantly decreased after embryo stage (P<0.05). This indicates that variability in $E_2$ at different stage is associated with the development of the oocytes. Plasma levels of $17{\alpha}$, $20{\beta}$-dihydroxy-4-pregnen-3-one (DHP) were significantly high at the stages of vitellogenesis and ovulation (P<0.001). It is assumed that DHP plays an important role in vitellogenesis. Also, We determined the plasma levels of vitellogenin (VTG) divided the development stage into four steps: immaturation, vitellogenesis, and ovulation and parturition. A significant lower levels of VTG were shown in immaturation and parturition (P<0.05), which did not discriminate between them. However, in vitellogenesis and ovulation were shown in a remarkable higher levels of VTG(P<0.05), but not significantly different between them. Consequently, plasma VTG levels were considerably increased after October and maintained a higher concentration until ovulation, but significantly decreased after ovulation. It is suggested that VTG plays also an important role in the development of vitellogenesis and oogenesis.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.303-313
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• 1982

The study was conducted to find out the concentrations of sex hormones and the contents of metabolites in serum, and the changes of weights and tissues on ovary, thyroid gland and adrenal gland according to gestation period in rabbit. The results were summarized as follows: 1. The ovary weights were increased significantly with the time e lapse after gestation and recovered normally at 5 days after parturition. In the histological changes of ovary, the lutein cells were hypertrophied and the secretory granules were increased actively until 3 weeks after gestation, and then a trophied thereafter. 2. The thyroid gland weights at all observation times were higher than those in control group, and the significance was recognized at 1, 3 and 4 weeks after gestation. The histological features of the secretory epithelium were the hyper trophic and columnar condition stimulating the functional state from 1 week after gestation. 3. The adrenal gland weights in experimental group were recognized significantly at 4 weeks after gestation, but showed higher than those in control group at all observation times. The zona fasciculata and zona reticularis of the gland showed the slight hypertrophic condition, but the zona glomeerulosa and adrenal medulla did not find out any particular changes. 4. The serum concentrations of progesterone and LH reached a peak level at 2 weeks and 1 week after geestation respectively, and rapidly began to decline thereafter. 5. The serum concentrations of estradiol-$17{\beta}$ and FSH were not detected below 20.0 pg/ml and 1.3 mIU/ml respectively. 6. The contents of total protein and non-protein nitrogen nitrogen were decreased gradually with the time elapse after gestation, but the significant differences were recognized from 3 weeks. 7. The total lipids were not changed markedly until 3 weeks, but increased significantly at 4 weeks after gestation and at 5 days after parturition. 8. The serum cholesterol tended to be decreased until 3 weeks, but increased at 4 weeks after gestation and at 5 days after parturition. 9. The serum calcium showed a continuous decrease during the gestation period, but the significant differences were recognized at 3 and 4 weeks. The serum phosphorus also had a significant decrease at 4 weeks after gestation.

• Development and Reproduction
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• v.6 no.2
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• pp.105-110
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• 2002

Numerous hormones are involved in the regulation of reproduction. Among them, estrogen and progesterone are the most important ovarian steroid hormones regulating female fertility. On the other hand, diverse stressors impede female receptivity and fertility. Since norepinephrine(NE) and epinephrine(E) are released from the adrenal during stress, it might play a role in stress-induced disruptions of fEmale reproductive parameters. The present study was performed to analyze the changes in adrenal catecholaminergic activities in cycling rats. The tissue content and secretion level of catecholamines were determined by high performance liquid chromatography coupled with electrochemical detector(HPLC-ECD). Adrenomedullary content of norepinephrine(NE) was increased on proestrus stage (59.47 $\pm$ 6.86 ug/gland), peaked on diestrus I stage(65.22 $\pm$ 5.99 ug/gland), and was nadir on diestrus II stage(41.63 $\pm$ 1.33 ug/gland). The highest E content was observed on proestrus stage(361.86 $\pm$ 15.58 ug/gland) while the lowest level was on diestrus II stage(285.58 $\pm$ 12.25 ug/gland). In addition to these observations, a significant reduction of the NE : E ratio was observed (1 : 4.81 on diestrus I vs 1 : 6.13～7.02 on other stages). In vitro secretion of adrenal NE and E was increased on proestrus stage, peaked on estrus stage, and decreased on diestrus II stage. Interestingly, the NE : E ratio in conditioned media was significantly increased on estrus stage (1 : 3.32 vs 1 : 2.34～2.65 on other stages. The biosynthesis of NE and E is mediated by tyrosine hydroxylase(TH) and phenylethanolamine-N-methyltransferase(PNMT) which acts conversion of tyrosine into DOPA and NE into E, respectively. These finding demonstrated that sex steroids, during setrous cycle, seem to be able to modify the adrenal catecholamines biosynthesis and secretion with stage-specific manner by modulation of the enzyme activities.

• Korean Journal of Animal Reproduction
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• v.27 no.1
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• pp.45-51
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• 2003

This study was conducted to investigate the effects of castration and ovariectomy on growth performance and plasma hormone concentration in pigs. A total of 48 pigs of 35 days of age were used. The results obtained in the present study are summarized as follows: 1. No significant difference was found in average daily gain between ovariectomy group (898.6g) and control gilt group (862.7g), and between castration group (926.0g) and control boar group (945.5g), respectively. Average daily gain of control boar group, however, was significantly higher than that of control gilt group (p<0.05). There was no significant difference in feed/gain between ovariectomy and control gilt group and between castration and control boar group, respectively. Backfat thickness was significantly (p<0.05) higher in ovariectomy or castration group than in control gilt or boar group, respectively. 2. Plasma concentration of IGF-I was significantly (p<0.05) increased during the period of 5 weeks of age (45.1 $\pm$0.72 ng/ml) to 15 weeks of age (356.3$\pm$3.05 ng/ml), and maintained constantly afterwards in control gilt group, as was in control boar group. That of ICF-I tended to be lower in ovariectomy or castration group than in control gilt or boar group, respectively. Regarding steroid hormones of estradiol-17$\beta$, progesterone, and testosterone, the concentration was extremely low at 5 weeks of age, however, increased from 11 weeks to 23 weeks of age in control gilt or boar group, while it was nearly under detection limit in ovariectomy or castration group. 3. Chemical compositions of pork loins were not affected by ovariectomy or castration, except that crude ash content was significantly (p<0.05) higher in castration group than in control boar group. These results indicated that ovariectomy or castration had no effects on growth performance and feed utilization. However, the concentration of sex steroid hormones was under detection limit in ovariectomy and castration group. Further studies, however, are needed to develope the techniques which minimize the stress related with castration or ovariectomy for the production of high quality pork.