• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.249-254
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• 2000

This study was carried out to investigate the possibility of dehydroepiandrosterone sulphate(DHEAS) as a stress hormone. Experiment 1) We evaluated the variation of DHEAS levels of long-term(30minutes a day fur 3 weeks) 37$^{\circ}C$ thermal stressed mice compared with that of cortisol. Serum concentrations of cortisol and DHEAS were measured by radioimmunoassay(RIA). Cortisol levels were not significantly altered both LW(Long-term stressed group, mice were killed without rest) and LR(Long-term stressed group, mice were killed after 4 days' rest) compared with control group, but DHEAS levels were decreased in LW compared with control group(p<0.05), and it kept a sustained difference after 4 days' rest(LR)(p<0.05). Experiment 2) We evaluated the changes of DHEAS levels on term of stress and rest. As stress term was longer, serum DHEAS levels were decreased and also kept a sustained difference after 10 days' rest compared with control group(p<0.05). These results suggest that cortisol has difficulty in taking an accurate measurement after extinction of stimuli, whereas DHEAS is more accurate and stable. Thus, this study implies that DHEAS is a stress-related hormone.

• Journal of Life Science
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• v.25 no.2
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• pp.151-157
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• 2015

Zebrafish (Danio rerio) has been more widely used to study pharmacology. Oxytectracycline (OTC) is a broad-spectrum antibiotic and works by interfering with the ability to produce essential proteins of bacteria. The aim of this study was to identify the effects of exposure to OTC on behavioral changes or endocrine response in zebrafish. The behavioral effects of exposure to OTC (50, 100 or 200 mg/l) were characterized in several novelty-based paradigms such as the novel tank or open field test in zebrafish. Moreover, to investigate effects of exposure to OTC on endocrine response, we measured whole-body cortisol level using cortisol ELISA kit. As results of novel tank test, duration in top and immobile duration were significantly increased by the exposure to OTC in a concentration-dependent manner (p<0.05). In addition, moving distance, highly mobile, velocity and zone transition were significantly decreased by the exposure to OTC in a concentration-dependent manner (p<0.05). As results of open field test, the exposure to OTC increased immobile duration significantly (p<0.05). However, moving distance, mobile duration and velocity were significantly decreased by the exposure to OTC in a concentration-dependent manner (p<0.05). Besides, the exposure to OTC elevated whole-body cortisol levels in zebrafish. These results suggest that the exposure to OTC may induce chemical stress in zebrafish.

• Journal of Dairy Science and Biotechnology
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• v.34 no.1
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• pp.37-41
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• 2016

Melatonin is a hormone produced by the pineal gland in dark conditions. It plays a major role in the regulation of the sleep-wake cycle. Melatonin synthesis is known to be suppressed by environmental light. Cortisol is a steroid hormone that is a major indicator of physiological alterations due to stressful stimuli. It also displays a circadian rhythm, like melatonin. The highest levels are encountered during early morning and the lowest levels are observed at around midnight. In the present study, the effects of milking time on the melatonin and cortisol concentrations of raw milk and milk powder at the summer and winter solstices were examined. The melatonin concentration in milk increased significantly if cows were milked in the dark at night (p<0.05). The melatonin concentration in milk powder showed the same pattern with respect to the milking time (p<0.05). However, no significant difference in the cortisol concentration was observed between day- and night-time milk. Although the time of day did not affect the level of milk cortisol, seasonal factors affected the release of cortisol in milk (p<0.05). In conclusion, night-time milk is rich in endogenous melatonin. In this respect, it has potential applications for the development of melatonin rich-dairy products, which serve as natural sources of melatonin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.1
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• pp.73-80
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• 2020

Psychological stress can affect the physiological condition of the skin and cause various cutaneous disorders. The stress hormone cortisol is secreted by various skin cells such as fibroblasts, keratinocytes, and melanocytes. Tight junctions (TJs) are cell-cell junctions that form a barrier in the stratum granulosum of mammalian skin. TJs can also affect other skin barriers and are affected by chemical, microbial, or immunological barriers. Stress can cause damage to the skin barrier. Interestingly, to our knowledge, there has not been any research demonstrating the involvement of TJs in this process. In this study, cortisol was used to treat keratinocytes to determine its role in regulating TJs. We found that cortisol damaged skin barrier function by regulating the gene expression and structure of TJ components. Cortisol also inhibited the development of the granular layer in a skin equivalent model. These results suggest that cortisol affects the skin barrier function by the regulation of TJs.

• Animal Bioscience
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• v.35 no.3
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• pp.503-510
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• 2022

Objective: This study was performed to determine the effects of stress after road transportation and oral administration of chromium and meloxicam on growth performance, plasma cortisol, serum metabolites, and behavior in dairy calves. Methods: A total of 50 Holstein heifers (average body weight [BW]: 172±4.19 kg; average age: 5.53±0.12 months) were randomly assigned to five groups including NL (not transported + D-lactose; 1 mg/kg BW), TL (transported + D-lactose; 1 mg/kg BW), TC (transported + chromium; 0.5 mg/kg dry matter [DM] feed), TM (transported + meloxicam; 1 mg/kg BW), and TMC (transported + combination of meloxicam and chromium; 1 mg/kg BW and 0.5 mg/kg DM, respectively). Doses of D-lactose monohydrate, meloxicam, and chromium were prepared for oral administration by suspension in 15 mL of water in a 20-mL dosing syringe. Blood was collected before transportation, immediately after 120 km of transportation (IAT), and at 6, 24, and 48 h after transportation. Results: Neither transportation nor administration of meloxicam and/or chromium affected (p = 0.99) average daily gain and feed intake. Plasma cortisol concentrations in the NL group (average 0.13 and 0.18 nmol/L, respectively) were lower (p<0.001) compared to the TL group (average 0.39 and 0.61 nmol/L, respectively) at IAT and 48 h after transportation. At 48 h after transportation, cortisol concentrations were lower (p<0.05) in the TC group (average 0.22 nmol/L) than in the TL group (average 0.61 nmol/L), and TC calves had similar cortisol concentrations to NL calves. Lying duration (min/d) was shorter (p<0.05) in the TL group than in the NL group at 2 d after transportation. Lying duration was longer (p<0.05) for the TC and TMC groups than for the TL group at 2 d after transportation. Conclusion: Transportation increased cortisol concentrations and affected lying behavior, while chromium administration reduced cortisol concentrations and changed lying behavior. Thus, chromium administration before transportation may be a viable strategy to alleviate stress elicited by road transportation.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.895-900
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• 2016

The present study aims to confirm the influence of a horse-riding lesson program (HRLP) on the stress level of horses and riders by respectively analyzing their salivary cortisol concentration. Twenty-four healthy horses and 23 riders participated in this study. The horses were randomly classified into two groups for the horse riding lesson program: Class 1 (for the beginner lesson) and Class 2 (for the intermediate lesson). The Class 1 group consisted of 12 horses and 12 riders, while the Class 2 group consisted of 12 horses and 11 riders. Salivettes cotton wool swabs were used for saliva collection and the saliva analyses were conducted using a two-way analysis of variance for repeated measures with SAS version 8. As for the results, the average salivary cortisol concentration of all horses before HRLP significantly increased compared to the baseline (p<0.001) while it decreased after the HRLP. The results of the salivary cortisol concentration of the riders were similar to the horses' results. However, there was no difference during the HRLP between Class 1 and Class 2 in the horse or rider groups. The results suggest that the HRLP did not influence the stress level of the horses or riders. Thus, this study provides the necessary information and guidelines for future studies on stress in horses during riding and gives insight into better horse welfare and management options.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.636-645
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• 2017

The physiological response of the longtooth grouper, Epinephelus bruneus to low water temperature (LWT) stress while on three different concentrations of dietary vitamin E (1 mg/diet g, 5 mg/diet g, and 10 mg /diet g) were investigated. Plasma cortisol, glucose, and aspartate aminotransferase (AST) levels were higher in the control and sham control compared with the vitamin E supplemented groups. The most addition with vitamin E in the diet (10 mg/diet g) showed the lowest levels of cortisol, glucose, and AST. However, plasma alanine aminotransferase (ALT) showed no significant differences across all experimental conditions (P>0.05). Also the more disposing vitamin E into feeding the better resistance against stress on the LWT was shown through cortisol, glucose, ALT, and AST.

• Journal of Korean Academy of Nursing
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• v.44 no.4
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• pp.446-457
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• 2014

Purpose: This study was done to evaluate the effects of psychosocial interventions on cortisol and immune response in adult patients with cancer. Methods: MEDLINE via PubMed, Cochrane Library CENTRAL, EMBASE, CINAHL and domestic electronic databases were searched. Twenty controlled trials (11 randomized and 9 non-randomized trials) met the inclusion criteria with a total of 862 participants. Methodological quality was assessed using the Cochrane's Risk of Bias for randomized studies and the Risk of Bias Assessment tool for non randomized studies. Data were analyzed using the RevMan 5.2.11 program of Cochrane library. Results: Overall, study quality was moderate to high. The weighted average effect size across studies was -0.32 (95% CI [-0.56, -0.07], p=.010, $I^2 $=45%) for cortisol concentration, -0.62 (95%CI [-0.96,-0.29], p<.001, $I^2 $=0%) for T lymphocyte (CD3) and -0.45 (95%CI [-0.74, -0.16], p=.003, $I^2 $=0%) for Th lymphocyte (CD4) numbers. Psychosocial interventions were not effective for Tc lymphocyte (CD4), NK cell, monocyte, and cytokine response. Conclusion: Although these results provide only small evidence of successful immune modulation, they support the conclusion that psychosocial interventions can assist cancer patients in reducing emotional distress and improving immune response.

• Development and Reproduction
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• v.19 no.1
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• pp.19-24
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• 2015

This study was conducted to determine the stress response [ethological (operculum movement number (OMN)), hematological (hematocrit and hemoglobin), biochemical (glucose, cortisol and glutamic oxaloacetic transaminase (GOT))] in red spotted grouper, Epinephelus akaara during exposure of different water temperature in winter season. This species (Total length, $18.56{\pm}0.34cm$) previously maintained in water temperature of $15^{\circ}C$ were transferred to 15, 20 and $25^{\circ}C$. During experimental period (7 days), OMN, hematocrit (Ht), glucose and GOT values were significantly high in $15^{\circ}C$ when compared to 20 and $25^{\circ}C$. Hemoglobin value was also increased at $15^{\circ}C$, but no significant differences. There was no differences in cortisol levels among the temperature groups. No fish mortality was observed during the experimental period. From these results, $15^{\circ}C$ is likely more stressful to red spotted grouper than $20^{\circ}C$ and $25^{\circ}C$. These observations confirm that red spotted grouper adapts better to temperatures between 20 and $25^{\circ}C$ during the winter season.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.1
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• pp.57-61
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• 1996

Four castrated Corriedale sheep were used in an experiment to observe the changes in insulin, growth hormone and cortisol in blood plasma following a prolonged infusion of a high rate of somatostatin (SRIF). The animals wee infused with either saline, 25 or $50{\mu}g/kg/h$ of SRIF for 3 hours. Blood samples wee taken every 20 minutes until 1 hour following the end of the SRIF infusion. Both SRIF infusion levels suppressed the release of insulin into plasma to approximately 3.5 mU/l. The SRIF infusions reduced the concentration of growth hormone to barely detectable levels. Following the withdrawal of SRIF there was a massive release of growth hormone. The plasma concentration of growth hormone reached 60 ng/ml within 20 minutes, the length of the growth hormone discharge was in excess of 1 hour. The extent of the discharge of growth hormone following the SRIF infusions was greater than that suppressed by the infusion. The SRIF apparently caused an increase in the plasma concentration of cortisol at the end of the infusion and following is withdrawal. This is possibly associated with some change in the metabolic rate associated with the suppression of insulin or glucagons release. The present experiment demonstrates that a high rate of SRIF infusion can not completely inhibit the release of insulin into the plasma.