• Development and Reproduction
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• v.13 no.4
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• pp.321-327
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• 2009

This study aimed to examine the testis toxicities of metal compound, manganese (Mn), which may be generated as mist or fume in the industrial sites. As well as serum prolactin (PRL) concentration was analyzed because Mn accumulation in basal ganglia up-regulates serum PRL and hyperprolactinemia consecutively induces the testis toxicity. Male F344 rats were divided into the 4 groups (2 controls and 2 Mn treated groups, n=10) on the basis of the test condition (inhalation, Mn $1.5mg/m^3$ or not) and treatment period (for 4-weeks and 13-weeks). The treatment time was 6 hr. a day, 5 days a week for the whole body. Basic tests including changes in body weight, feed rate were observed. Blood and testis Mn concentration, and testis toxicity test such as the number and deformity test of sperm were also observed. Serum PRL level was analyzed by ELISA to certify the relationship between the Mn induced increase of the serum PRL level and sperm production. Blood and testis Mn concentrations were significantly and dose-dependently increased. Sperm count was decreased in Mn-treatment groups than control in a treatment time dependent manner. Morphological analysis of cauda epidydimal sperm showed that the frequencies of morphologically abnormal sperms such as bent tail and small head were increased in the both Mn-treatment groups than control. A significant increase in serum PRL levels was found in response to Mn treatment but it was not hyperprolactinemia range. These results suggest that treatment of Mn up-regulates the serum PRL concentration and induces the testis toxicity. The No Aversed Effect Level (NOAEL) of inhaled Mn on the male rat testis may be under the $1.5mg/m^3$.

• Journal of Korean Neurosurgical Society
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• v.40 no.5
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• pp.330-335
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• 2006

Objective : The aim of the study was to review the clinical and radiological findings of those non-functioning adenomas[NFAs] with positive immnoreactivity for anterior pituitary hormones. Methods : Sixty patients with pituitary adenoma were treated at the author's institution between January 2000 and July 2005. All consecutive patients were underwent transsphenoidal surgery by same operator. In addition to the routine histopathological examination, surgical specimen was examined by immunohistochemical staining against adenohypophyseal cells. And clinical analysis was performed by retrospective review of medical records, neuroimaging examinations and immunohistochemical technique. We classified these pituitary adenomas into functioning adenomas [group F], immuno-positive NFAs [group S, so-called silent adenoma] and immuno-negative NFAs [group N], and compared clinical and radiological differences between group F, N, and S. Results : Of the 60 cases, group F was 25, group S was 25, and group N was 10. Among the group S, 5 cases showed reactivity against PRL, 1 against GH, 1 against both PRL and GH, 1 against TSH and GH, 2 against ACTH, 11 against FSH and 4 against both LH and FSH. Radiologically, invasiveness was noted in 8 in group S, compared to 3 in group N and 1 in group F [p = 0.02]. Intratumoral bleeding was noted in 7 of group S, 2 of group N and 2 of group F [p >0.05]. Conclusion : Silent adenomas were thought to behave more aggressive than other subgroups of pituitary adenomas. And so we suggest the immunohistochemical study against adenohypophyseal cells may be helpful for evaluating clinical course of pituitary adenoma, expecially for, NFAs.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.155-162
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• 2001

These experiments were conducted to evaluate the effects of the administration of exogenous PG $F_{2{\alpha}}$ on hormone concentrations and follicular development in early postpartum(pp) Korean native goats. 1. Plasma PG $F_{2{\alpha}}$ concentrations in PG $F_{2{\alpha}}$ treated goals showed a gradual increase from a low on day 2 (GR-1 : 10 day-treatment group: 6.35$\pm$0.5 and GR-2; 4 day-treatment group: 0.22$\pm$0.2 pg/$m\ell$, respectively) to reach a peak of 21.18$\pm$1.6 or 4.21 $\pm$0.4 pg/$m\ell$ on day 4 after treatment of PG $F_{2{\alpha}}$. 2. Plasma PG $F_{2{\alpha}}$ concentrations in GR-1 goats averaged 9.08 $\pm$1.2 pg/$m\ell$ compared with 5.44$\pm$ 1.8 pg/$m\ell$ in GR-2 goats the day before treatment of PG $F_{2{\alpha}}$. Mean PG $F_{2{\alpha}}$ concentrations thereafter remained low during the treatment period but PG $F_{2{\alpha}}$ concentrations did not differ between the two group. 3. Plasma concentrations of estradiol-17 $\beta$ (E,) in PG $F_{2{\alpha}}$ - treated group were decreased gradually until 2 days after PG $F_{2{\alpha}}$ treatment but mean $E_2$ concentrations began to increase on 3 days and were Inaximal on the 4 days after treatment. 4. Plasma lulenizing hormone (LH) concentrations in PG $F_{2{\alpha}}$ - treated goats were slightly higher than in controls but mean LH concentrations did not differ between the two treatment groups. 5. Plasma prolactin (PRL) concentrations were suppressed in both GR-1(10 day-treatment group) and GR-2(4 day-treatment group) goats compared to saline controls but mean PRL concentrations remained lower in PG $F_{2{\alpha}}$ treated animals during post-treatment period. 6. The mean number of small and medium follicles present when PG $F_{2{\alpha}}$ was administrated was similar in all does but the increase in number of large follicles($\geq$4mm) tended to be higher in PG $F_{2{\alpha}}$ treated group than controls. These results suggest that concentrations of PG $F_{2{\alpha}}$ and estradiol-17$\beta$ were positively correlared with follicular diameter. We conclude that PG $F_{2{\alpha}}$ treatment stimulates follicular development similarly in both GR-1 and GR-2 group.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.987-996
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• 2018

Bacterial programmed cell death is regulated by the toxin-antitoxin (TA) system. YhaV (toxin) and Pr1F (antitoxin) have been recently identified as a type II TA system in Escherichia coli. YhaV homologs have conserved active residues within the C-terminus, and to characterize the function of this region, we purified native YhaV protein (without denaturing) and constructed YhaV proteins of varying lengths. Here, we report a new low-temperature method of purifying native YhaV, which is notable given the existing challenges of purifying this highly toxic protein. The secondary structures and thermostability of the purified native protein were characterized and no significant structural destruction was observed, suggesting that the observed inhibition of cell growth in vivo was not the result of structural protein damage. However, it has been reported that excessive levels of protein expression may result in protein misfolding and changes in cell growth and mRNA stability. To exclude this possibility, we used an [$^{35}S$]-methionine prokaryotic cell-free protein synthesis system in vitro in the presence of purified YhaV, and two C-terminal truncated forms of this protein (YhaV-L and YhaV-S). Our results suggest that the YhaV C-terminal region is essential for mRNA interferase activity, and the W143 or H154 residues may play an analogous role to Y87 of RelE.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.4
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• pp.571-579
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• 2016

In this work, we prepared a panel of monoclonal anti-idiotypic antibodies to ovine prolactin (oPRL) by the hybridoma technique. Among these antibodies, one anti-idotypic antibody (designated B7) was chosen for further characterization by a series of experiments. We first demonstrated that B7 behaved as a typical $Ab2{\beta}$ based on a series of enzyme-linked immunosorbent assays. Subsequently, the results of a competitive receptor-binding assay confirmed that B7 could specifically bind to the prolactin receptor (PRLR) expressed on target cells. Finally, we examined its biological activities in CHO-PRLR and Nb2 cells and observed that B7 could activate Janus kinase 2-signal transducer and activator of transcription signalling in CHO-PRLR and Nb2 cells and induce BaF3 proliferation. The present study suggests that i) B7 can serve as a PRLR agonist or PRL mimic and has potential applications in regulating mammary gland development, milk production and maintenance of lactation in domestic animals and ii) B7 may be a biological reagent that can be used to explore the mechanism of PRLR-mediated intracellular signalling.

• Journal of Preventive Medicine and Public Health
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• v.38 no.3
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• pp.330-336
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• 2005

Objectives : The aim of this study was to investigate the effects of bisphenol A (BPA), an estrogen-like environmental endocrine disrupter, on the placental function and reproduction in rats. The mRNA levels of the placental prolactin-growth hormone(PRL-GH) gene family, placental trophoblast cell frequency and reproductive data were analyzed. Methods : The pregnancies of F344 Fisher rats ($160g{\pm}20g$) were detected by the presence of the copulatory plug or sperm in the vaginal smear, which marked Day 0 of pregnancy. Pregnant rats were divided into three groups. The control group was intraperitoneally injected with a sesame oil vehicle. The two remaining groups were injected with 50 or 500 mg/kg B.W/day of BPA, resuspended in sesame oil, on either days 7 to 11 or 16 to 20 of pregnancy, with the rats sacrificed on either day 11 or 20, respectively. The mRNA levels of PRL-GH and Pit-1a and b isotype genes were analyzed by Northern blot hybridization and reverse transcription-polymerase chain reaction. The hormone concentrations were analyzed by radioimmunoassay, and the frequency of the placental trophoblast cells observed by a histochemical study. Reproductive data, such as the placental weight and litter size, were surveyed on day 20. The fetal weight was surveyed for 4 weeks after birth. A statistical analysis was carried out using the SAS program (version 8.1). Results : The mRNA levels of the PRL-GH gene family, such as placental lactogen I, Iv and II, prolactin like protein A, C and Cv, and decidual prolactin-related protein were significantly reduced due to BPA exposure. The mRNA levels of the Pit-1a and b isotype genes, which induce the expression of the PRL-GH gene family in the rat placenta, were also reduced due to BPA exposure. The PL-Iv and PL-II concentrations were reduced in the BPA exposed group. During the middle to last stage of pregnancy (Days 11-20), a high dose of BPA exposure reduced the frequency of spongiotrophoblast cells, which are responsible for the secretion of the PRL-GH hormones. Reproductive data, such as the placental and fetal weights and the litter size, were reduced, but that of the pregnancy period was extended in the BPA exposed compared to the control group. Conclusions : BPA disrupts the placental functions in rats, which leads to reproductive disorders.

• Journal of Preventive Medicine and Public Health
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• v.37 no.2
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• pp.157-165
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• 2004

Objectives : This study aimed to investigate the toxic effects of chromium (VI) on the placental function and reproduction in rats. For the study, the placental prolactin-growth hormone (PRL-GH) gene expression, placental trophoblast cell differentiation and reproductive data were analyzed. Methods : The pregnancies of F344 Fisher rats were checked by the presence of a copulatory plug or sperm in the vaginal smear, which was defined as day 0 of the pregnancy. Pregnant rats were divided into the three groups. The control group was given tap water (chromium level < 0.001 ppm) and the remaining groups were given 250 or 750 ppm of chromium (VI) [as potassium dichromate], from day 7 to 19 of the pregnancy. Rats were sacrificed at days 11 and 20 of pregnancy. The mRNA levels of PRL-GH and Pit-1a and b isotype genes were analyzed by Northern blot hybridization and reverse transcription-polymerase chain reaction (RT-PCR). The hormonal concentration was analyzed by radioimmunoassay, and the differentiation of placental trophoblast cells were observed by histochemical studies. Reproductive data, such as placental and fetal weights, pregnancy period, and litter size, were surveyed at day 20 of pregnancy and after birth. A statistical analysis was carried out using the SAS program (version 8.1). Results : The mRNA levels of the prolactin-growth hormone (PRL-GH) family of genes were dose dependently reduced by chromium exposure. The mRNA levels of Pit-1a and b isotype genes that induce the expression of the PRL-GH family of genes were also reduced by chromium exposure. The PRL-GH hormonal concentration in the rat placenta, fetus and maternal blood were decreased by chromium exposure. In the middle stage of pregnancy (day 11), a high dose of chromium suppressed the differentiation of spongiotrophoblast cells that secret the PRLGH hormones. In the last stage of pregnancy (day 20), a high dose of chromium induced apoptosis of placental cells. Reproductive data, such as placental and fetal weights, litter size, were reduced, but the pregnancy period was extended in the group exposed to chromium compared with the controls. Conclusion : Chromium (VI) disrupts the ordered functions of the placenta, which leads to reproductive disorders in rats.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1342-1348
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• 2007

POU1F1 is a positive regulator for GH, PRL and TSH${\beta}$ and its mutations associate with production traits in ruminant animals. We described a DdeI PCR-RFLP method for detecting a silent allele in the goat POU1F1 gene: TCT (241Ser)>TCG (241Ser). Frequencies of $D_1$ allele varied from 0.600 to 1.000 in Chinese 801 goats. Significant associations of DdeI polymorphism with production traits were found in milk yield (*p<0.05), litter size (*p<0.05) and one-year-old weight (*p<0.05) between different genotypes. Individuals with genotype $D_1D_1$ had a superior performances when compared to those with genotype $D_1D_2$ (*p<0.05). Hence, the POU1F1 gene was suggested to the potential candidate gene for superior milk performance, reproduction trait and weight trait. Genotype $D_1D_1$, characterized by a DdeI PCR-RFLP detection, was recommended to geneticists and breeders as a molecular marker for better performance in the goat industry.

• Korean Journal of Animal Reproduction
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• v.22 no.1
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• pp.29-34
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• 1998

Jugular plasma concentrations of luteinizing hormone, prolactin, estradiol-17\ulcorner and 13, 14-dihydro-15-keto-prostaglandin-F2봬(PGFM) were meausred prepartum during the last 12 days of pregnancy, at parturition, then 1 day after parturition in 16 goats. Plasma samples were analyzed for luteinizing hormone(LH), estradiol-17\ulcorner(E2), prolactin(PRL) and prostagladin F2봬(PGF2봬) concentrations by radioimmunoassay. 1. The concentrations of plasma luteinizing hormone in Korean native goats remained fairly constant(0.20 0.02\ulcorner0.38 0.04 mlu/ml) from 12 days prepartum to 1 postpartum but the concentrations of plasma prolactin rose slightly from 1 day prepartum. 2. The estradiol-17\ulcorner concentrations increased rapidly after day 1 before partum, reaching a peak at parturition(74.8 77.5 pg/ml), and falling to 63.8 2.8 pg/ml at day 1 postpartum. 3. Starting at 323.2 69.6 twelve days before parturition, the concentrations of plasma prostaglandin F2봬 rose during the 1 day preceeding parturition(650.7봬57.8 pg/ml) and peaked at 1081.4 164.9 on the day of parturition. At day 1 postpartum, the concentrations of PGF2봬 decreased to 425.3 60.4 pg/ml. Finally, these results show that changes in prostaglandin F2봬 concentrations before parturition were closely related to changes in estradiol-17\ulcorner concnetrations, but after parturition they remained elevated whereas estradiol-17\ulcorner concentrations fell abruptly.