• The Korean Journal of Physiology and Pharmacology
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• v.10 no.5
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• pp.273-282
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• 2006

The aim of the present study was to investigate the effects of R-(-)-2,10,11-trihydroxy-N-propylnoraporphine [R-(-)-TNPA], a selective agonist of dopaminergic $D_2$ receptor and S(-)-raclopride, a selective antagonist of dopaminergic $D_2$ receptor, on the secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane-depolarization in the isolated perfused model of the rat adrenal gland, and also to establish its mechanism of action. R-(-)-TNPA $(10{\sim}100\;{\mu}M)$ perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (56 mM), DMPP $(100\;{\mu}M)$ and McN-A-343 $(100\;{\mu}M)$. R-(-)-TNPA itself did also fail to affect basal CA output. Also, in adrenal glands loaded with R-(-)-TNPA $(30\;{\mu}M)$, the CA secretory responses evoked by Bay-K-8644 $(10\;{\mu}M)$, an activator of L-type $Ca^2+$ channels and cyclopiazonic acid $(10\;{\mu}M)$, an inhibitor of cytoplasmic $Ca^{2+}-ATPase$ were also inhibited. However, S(-)-raclopride $(1{\sim}10\;{\mu}M)$, given into an adrenal vein for 60 min, enhanced the CA secretory responses evoked by ACh, high $K^+$, DMPP and McN-A-343 only for the first period (4 min), although it alone has weak effect on CA secretion. Moreover, S(-)-raclopride $(3.0\;{\mu}M)$ in to an adrenal vein for 60 min also augmented the CA release evoked by BAY-K-8644 and cyclopiazonic acid only for the first period (4 min). However, after simultaneous perfusion of R-(-)-TNP A $(30\;{\mu}M)$ and S(-)-raclopride $(3.0\;{\mu}M)$, the inhibitory responses of R(-)-TNPA $(30\;{\mu}M)$ on the CA secretion evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644, and cyclopiazonic acid were significantly reduced. Taken together, these experimental results suggest that R-(-)-TNPA greatly inhibits the CA secretion from the perfused rat adrenal medulla evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) and membrane depolarization, but S(-)-raclopride rather enhances the CA release by them. It seems that this inhibitory of R-(-)-TNPA may be mediated by stimulation of inhibitory dopaminergic $D_2$ receptors located on the rat adrenomedullary chromaffin cells, while the facilitatory effect of S(-)-raclopride is due to the blockade of dopaminergic $D_2$ receptors, which are relevant to extra- and intracellular calcium mobilization. Therefore, it is thought that dopaminergic $D_2$ receptors may be involved in regulation of CA release in the rat adrenal medulla.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.1
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• pp.13-23
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• 2008

The aim of the present study was designed to establish comparatively the inhibitory effects of $D_1$-like and $D_2$-like dopaminergic receptor agonists, SKF81297 and R(-)-TNPA on the release of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from the isolated perfused model of the rat adrenal medulla. SKF81297 $(30{\mu}M)$ and R-(-)-TNPA $(30{\mu}M)$ perfused into an adrenal vein for 60 min, produced great inhibition in the CA secretory responses evoked by ACh $(5.32{\times}10^{-3}\;M)$, DMPP $(10^{-4}\;M)$, McN-A-343 $(10^{-4}\;M)$, high $K^+$ $(5.6{\times}10^{-2}\;M)$, Bay-K-8644 $(10{\mu}M)$, and cyclopiazonic acid $(10{\mu}M)$, respectively. For the release of CA evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid, the following rank order of inhibitory potency was obtained: SKF81297>R-(-)-TNPA. However, R(+)-SCH23390, a selectve $D_1$-like dopaminergic receptor antagonist, and S(-)-raclopride, a selectve $D_2$-like dopaminergic receptor antagonist, enhanced the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid only for $0{\sim}4$ min. The rank order for the enhancement of CA release evoked by high $K^+$, McN-A-343 and cyclopiazonic acid was R(+)-SCH23390>S(-)-raclopride. Also, the rank order for ACh, DMPP and Bay-K-8644 was S(-)-raclopride > R(+)-SCH23390. Taken together, these results demonstrate that both SKF81297 and R-(-)-TNPA inhibit the CA release evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors and the membrane depolarization from the isolated perfused rat adrenal gland without affecting the basal release, respectively, but both R(+)-SCH23390 and S(-)-raclopride facilitate the CA release evoked by them. It seems likely that the inhibitory effects of SKF81297 and R-(-)-TNPA are mediated by the activation of $D_1$-like and $D_2$-like dopaminergic receptors located on the rat adrenomedullary chromaffin cells, respectively, whereas the facilitatory effects of R(+)-SCH23390 and S(-)-raclopride are mediated by the blockade of $D_1$-like and $D_2$-like dopaminergic receptors, respectively: this action is possibly associated with extra- and intracellular calcium mobilization. Based on these results, it is thought that the presence of dopaminergic $D_1$ receptors may play an important role in regulation of the rat adrenomedullary CA secretion, in addition to well-known dopaminergic $D_2$ receptors.

• The Journal of Internal Korean Medicine
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• v.27 no.3
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• pp.639-652
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• 2006

Objective : The etiology of chronic prostatitis is likely multifactorial, resulting from either a cascade of events after an initiating factor or from a variety of etiologic mechanisms. There is substantiating evidence to support the role of the inflammatory responses in its pathogenesis, and the clinical value in the evaluation of therapeutic efficacy. Forsythiae Frucus has been traditionally used in treatment of inflammatory diseases, including of prostatitis and urinary tract inflammation. In this study, we investigated the effects of Forsythiae Frucus on inflammatory cytokines and cyto-pathological alternation in the rat model of chronic non-bacterial prostatitis induced by castration and $17{\beta}$-estradiol treatment. Methods : Two-month-old rats were treated with $17{\beta}$-estradiol after castration for induction of experimental non-bacterial prostatitis. which is similar to human chronic prostatitis in histopathological profiles. Forsythiae Frucus as an experimental specimen, and testosterone as a positive control, were administered orally. The prostates were evaluated by histopathologlcal parameters including the epithelial score and epithelio-stromal ratio for glandular damage. and the expression of inflammatory cytokine genes including interleukin (IL)-$1{\beta}$, IL-5, IL-12, tumor necrosis factor (TNF)-$\alpha$. eotaxin, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2(cox-2). Results : While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation. the rats treated with Forsythiae Frucus showed a diminished range of tissue damage. Epithelial score was improved in the Forsythiae Frucus group over that of the control (P<0.05). The epithelia-stromal ratio was lower in the Forsythiae Frucus group when compared to that of the control (P<0.05). In the reverse transcription-polymerase chain reaction (RT-PCR) of inflammatory cytosine genes. Forsythiae Frucus inhibited the expression of IL-$1{\beta}$, TNF-$\alpha$, iNOS, cox-2 genes, while it modulated the expression of IL-5, which is an anti-inflammatory cytokine. Conclusions : These findings suggest that Forsythiae Frucus may protect the glandular epithelial cells and also inhibit stromal proliferation in association with the immune modulation including the suppression of inflammatory cytokines and increase of anti-inflammatory cytokines. From theses results. we suggest that Forsythiae Frucus could be a useful remedy agents for treating chronic non-bacterial prostatitis.

• Experimental and Molecular Medicine
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• v.50 no.11
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• pp.13.1-13.15
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• 2018

Wound healing is delayed in diabetic patients. Increased apoptosis and endothelial progenitor cell (EPC) dysfunction are implicated in delayed diabetic wound healing. Melatonin, a major secretory product of the pineal gland, promotes diabetic wound healing; however, its mechanism of action remains unclear. Here, EPCs were isolated from the bone marrow of mice. Treatment of EPCs with melatonin alleviated advanced glycation end product (AGE)-induced apoptosis and cellular dysfunction. We further examined autophagy flux after melatonin treatment and found increased light chain 3 (LC3) and p62 protein levels in AGE-treated EPCs. However, lysosome-associated membrane protein 2 expression was decreased, indicating that autophagy flux was impaired in EPCs treated with AGEs. We then evaluated autophagy flux after melatonin treatment and found that melatonin increased the LC3 levels, but attenuated the accumulation of p62, suggesting a stimulatory effect of melatonin on autophagy flux. Blockage of autophagy flux by chloroquine partially abolished the protective effects of melatonin, indicating that autophagy flux is involved in the protective effects of melatonin. Furthermore, we found that the AMPK/mTOR signaling pathway is involved in autophagy flux stimulation by melatonin. An in vivo study also illustrated that melatonin treatment ameliorated impaired wound healing in a streptozotocin-induced diabetic wound healing model. Thus, our study shows that melatonin protects EPCs against apoptosis and dysfunction via autophagy flux stimulation and ameliorates impaired wound healing in vivo, providing insight into its mechanism of action in diabetic wound healing.

• Development and Reproduction
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• v.22 no.4
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• pp.379-391
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• 2018

Through the development of organic synthetic skill, chemicals that mimic signaling mediators such as steroid hormones have been exposed to the environment. Recently, it has become apparent that this circumstance should be further studied in the field of physiology. Estrogenic action of chronic low-dose nonylphenol (NP) and di-(2-ethylhexyl) phthalate (DEHP) in mouse uterus was assessed in this study. Ten to twelve-week-old female mice (CD-1) were fed drinking water containing NP (50 or $500{\mu}g/L$) or DEHP (133 or $1,330{\mu}g/L$) for 10 weeks. Uterine diameter, the thickness of myometrium and endometrium, and the height of luminal epithelial cells were measured and the number of glands were counted. The expression levels of the known $17{\beta}$-estradiol ($E_2$)-regulated genes were evaluated with real-time RT-PCR methodology. The ration of uterine weight to body weight increased in $133{\mu}g/L$ DEHP. Endometrial and myometrial thickness increased in 133 and $1,330{\mu}g/L$ DEHP treated groups, and in 50, $500{\mu}g/L$ NP and $133{\mu}g/L$ DEHP, respectively. The height of luminal epithelial cell decreased in NP groups. The numbers of luminal epithelial gland were decreased in NP groups but increased in $50{\mu}g/L$ DEHP group. The histological characters of glands were not different between groups. The mRNA expression profiles of the known $17{\beta}$-estradiol ($E_2$) downstream genes, Esr1, Esr2, Pgr, Lox, and Muc1, were also different between NP and DEHP groups. The expression levels dramatically increased in some genes by the NP or DEHP. Based on these results, it is suggested that the chronic low-dose NP or DEHP works as estrogen-like messengers in uterus with their own specific gene expression-regulation patterns.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.1
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• pp.35-52
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• 2016

Objectives :The purpose of this study was to investigate the effect on factors related the expression of aquaporins (AQP) and milk production after administration of Boheotang-gagam in lactating mice. Methods: The SKH-1 mice were randomly allocated to the control group which was administered with distilled water for two weeks after the parturition and the experimental groups such as, lactating+400G group (L400G) which was administered with Boheotang-gagam 400 mg/day, lactating+600G group (L600G) which was administered with 600 mg/day for two weeks after the parturition, and 400G+lactating+400G group (400G-L400G) which was administered with 400 mg/day for 3 weeks starting one week prior to parturition for experiment (n=6 per group). Results: 1. With regard to the immunohistochemical staining reaction for AQP1, AQP3, and AQP5, stronger immune response was also showed in mammary gland in all experimental groups as compared to the control group. AQP1 showed stronger immune response in the capillaries and venules which were located around the interlobular duct, while stronger immune response of AQP3 and AQP5 showed in the secretory alveolar epithelia and intralobular and interlobular ductal epithelial cells. 2. In the western blot, L400G group showed the most increased expression followed by L600G and then 400G-L400G group in AQP1. In AQP3, the order of expression density was observed as L600G, 400G-L400G and L400G group. Lastly, in AQP5, L400G group presented the most increased expression followed by L600G and 400G-L400G group. Conclusions: Boheotang-gagam would have the effect of increasing the lactation of mice after the birth by increasing the prolactin level and adjusting the expression of AQPs and prolactin receptor in the mammary glands.

• Journal of Life Science
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• v.29 no.6
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• pp.705-711
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• 2019

Benign prostatic hyperplasia (BPH) is the most common urogenital disorder in men, benign tumor and is a typical disease deteriorating the quality of old men's lives, and its prevalence increases with age. Though the molecular pathogenesis of BPH has not yet been clearly revealed, it is known that the variation and aging of the endocrine including sex hormone may cause BPH. Especially the hypertrophy of the prostate cell by the formation of the excessive dihydrotestosterone (DHT) is estimated to cause BPH. If testosterone exists excessively in blood, a lot of DHT is produced in prostate by $5{\alpha}-reductase$. Thus, in this study we tried to analyze haematological change and histopathological change by using the model rat with BPH caused by hypodermic injection of testosterone to prove the effect of Houttuynia cordata extracts on BPH. Rats were divided into four experimental groups: no treatment group (N), the testosterone injection and D.W treatment group (DO), the testosterone injection and Houttuynia cordata treatment group (HO) and testosterone injection and finasteride treatment group (FO). Prostate weight, volume and weight ratio in the HO and FO groups were significantly lower than the DO group. Testosterone and DHT levels in the HO group were significantly lower than the DO group. The HO and FO groups showed trophic symptoms and were lined by flattened epithelial cells, thus, the stromal proliferation is relatively low as compared to the DO group. These results suggest that Houttuynia cordata may control benign prostatic hyperplasia.

• Natural Product Sciences
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• v.27 no.2
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• pp.86-98
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• 2021

This study was designed to characterize the effect of ginsenoside-Rg2 (Rg2), one of panaxatriol saponins isolated from Korean ginseng root, on the release of catecholamines (CA) in the perfused model of the rat adrenal medulla, and also to establish its mechanism of action. Rg2 (3~30 µM), administered into an adrenal vein for 90 min, depressed acetylcholine (ACh)-induced CA secretion in a dose- and time-dependent manner. Rg2 also time-dependently inhibited the CA secretion induced by 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyltrimethyl ammonium chloride (McN-A-343), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP), and angiotensin II (Ang II). Also, during perfusion of Rg2, the CA secretion induced by high K⁺, veratridine, cyclopiazonic acid, methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoro-methyl-phenyl)-pyridine-5-carboxylate (Bay-K-8644) depressed, respectively. In the simultaneous presence of Rg2 and N^ω-nitro-L-arginine methyl ester hydrochloride ʟ-NAME), the CA secretion induced by ACh, Ang II, Bay-K-8644 and veratridine was restored nearly to the extent of their corresponding control level, respectively, compared to those of inhibitory effects of Rg2-treatment alone. Virtually, NO release in adrenal medulla following perfusion of Rg2 was significantly enhanced in comparison to the corresponding spontaneous release. Also, in the coexistence of Rg2 and fimasartan, ACh-induced CA secretion was markedly diminished compared to the inhibitory effect of fimasartan-treated alone. Collectively, these results demonstrated that Rg2 suppressed the CA secretion induced by activation of cholinergic as well as angiotensinergic receptors from the perfused model of the rat adrenal gland. This Rg2-induced inhibitory effect seems to be exerted by reducing both influx of Na⁺ and Ca²⁺ through their ionic channels into the adrenomedullary cells as well as by suppressing Ca²⁺ release from the cytoplasmic calcium store, at least through the elevated NO release by activation of NO synthase, which is associated to the blockade of neuronal cholinergic and AT₁-receptors. Based on these results, the ingestion of Rg2 may be helpful to alleviate or prevent the cardiovascular diseases, via reduction of CA release in adrenal medulla and consequent decreased CA level in circulation.

• Animal Bioscience
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• v.35 no.3
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• pp.385-398
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• 2022

Objective: The objective was to evaluate the influence of different dietary crude protein (CP) levels during the growth phase on reproductive characteristics and reproductive efficiency as well as the body development of adult male Japanese quail. Methods: Three hundred one-day-old male quails were distributed into five treatments with diets containing different CP levels (18%, 20%, 22%, 24%, and 26%) in a completely randomized design, with six replicates of ten birds each. The CP diets were applied only during the growth phase (1 to 35 days). At 36 days of age, the birds were transferred to 30 laying cages with three males and nine females each, and all birds received the same diet formulated to meet production-phase requirements until 96 days of age. Results: The growth rate of the birds increased linearly (p<0.01) with increasing dietary CP, but the age of maximum growth decreased (p<0.05). At growth maturity, all birds had the same body weight (p>0.05). At 35 days of age, higher weight gain was obtained (p<0.05) with diets containing 22% CP or higher. No effects on feed conversion were observed in this phase. The increase in dietary CP enhanced (p<0.01) nitrogen intake and nitrogen excretion but did not affect (p>0.05) nitrogen retention. Testis size, seminiferous tubular area, number of spermatogonia, and germinal epithelial height at 35 days of age increased linearly (p<0.05) with dietary CP, while the number of Leydig cells decreased (p<0.01). The Sertoli cell number at 60 days of age increased linearly (p<0.01) with dietary CP. Dietary CP levels did not affect cloacal gland size, foam weight, foam protein concentration, semen volume, or flock fertility at 90 days of age. Conclusion: Dietary CP concentration affected body and testicular development in male Japanese quails but did not affect reproductive efficiency.

• Korean Journal of Veterinary Service
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• v.45 no.2
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• pp.79-86
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• 2022

Reproductive disorders in cows cause economic loss in livestock farms. This study was carried out to investigate the incidence of endometriosis in the uterine of Korean indigenous cow (Hanwoo). In the present study, the uterine of 25 cows was provided by the slaughterhouse. As a result on a visual examination of the uterus, 18 out of 25 were visually normal, and 7 uteruses (28%) appeared rather pale and showed purulent or mucosal symptoms in Uterine horn. However, the results of hematological analysis showed that both RBC and WBC were normal and showed no signs of systemic inflammation, indicating 7 cows showed asymptomatic endometriosis. The inflammatory uterus (28%) showed a wide range of pathological conditions that elicit an inflammatory response, such as serous exudate and bleeding. Histological and microscopic analysis in the inflammatory group demonstrated that there was swelling of the uterine glands, and neutrophil, basophil, and lymphocyte appeared in the uterine gland. Moreover, plasma cells and hemosiderin-laden macrophages were increased in the endometrial stroma, which lead to inhibit pregnancy by suppression of the synthesis of pregnancy hormones, and the appearance of hemosiderin-laden macrophages is an indicator of intracellular bleeding. In summary, hematologically, it is a normal diagnosis in Korean indigenous cows, however, when the uterus was extracted and investigated microscopically, the asymptomatic endometriosis were evident. In order to achieve the goal of healthy cow management and breeding within 2 weeks after birth, cows' uterus should be washed, disinfected, and through thorough the hygiene management, it aims to prevent asymptomatic endometriosis to produce healthy offspring and reduce the breeding interval.