• Clinical and Experimental Reproductive Medicine
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• 제40권4호
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• pp.155-162
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• 2013

Objective: Stress is known to be an inhibitor of the reproductive hypothalamic-pituitary-gonadal (HPG) axis. However, the neural and molecular connections between stress and reproduction are not yet understood. It is well established that in both humans and rodents, kisspeptin (encoded by the kiss1 gene) is a strong stimulator of the HPG axis. In the present study we hypothesized that endocannabinoids, an important neuromodulatory system in the brain, can act on the HPG axis at the level of kiss1 expression to inhibit reproductive function under stress. Methods: Adult male Wistar rats were unilaterally implanted with an intracerebroventricular cannula. Afterwards, the animals were exposed to immobilization stress, with or without the presence of the cannabinoid CB1 receptor antagonist AM251 (1 ${\mu}g/rat$). Blood samples were collected through a retro-orbital plexus puncture before and after stress. Five hours after the stress, brain tissue was collected for reverse transcriptase-quantitative polymerase chain reaction measurements of kiss1 mRNA. Results: Immobilization stress (1 hour) resulted in a decrease in the serum luteinizing hormone concentration. Additionally, kiss1 gene expression was decreased in key hypothalamic nuclei that regulate gonadotrophin secretion, the medial preoptic area (mPOA), and to some extent the arcuate nucleus (ARC). A single central administration of AM251 was effective in blocking these inhibitory responses. Conclusion: These findings suggest that endocannabinoids mediate, at least in part, immobilization stress-induced inhibition of the reproductive system. Our data suggest that the connection between immobilization stress and the HPG axis is kiss1 expression in the mPOA rather than the ARC.

• 대한약리학회지
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• 제30권1호
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• pp.39-48
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• 1994

포만중추 (satiety center)를 자극하여 음식섭취를 억제한다고 알려진 CCK-8을 흰쥐 복강에 투여하여, 흰쥐 뇌의 도파민 변화에 대한 CCK-8의 효과를 관찰하였다. 흰쥐 뇌의 부위별 도파민 함량은 HPLC-ECD방법으로 측정하였으며, 시상하부와 흑질에서의 TH-immunoreactive neuron은 면역조직화학법과 영상분석법을 시행하였다. 굶긴 쥐에서는 정상 쥐에 비하여, 도파민 함량이 전두 피질, 해마, 시상하부 및 편도체에서 각각 감소하였다. CCK-8을 투여한 쥐는 정상 쥐와 굶긴 쥐에 비하여, 도파민 함량이 시상하부에서 의미있게 감소하였다. 또한 굶긴 쥐는 정상 쥐와 비교하여, TH-positive neuron의 분포와 수가 뇌실옆핵, 깔때기핵, 정중융기 및 혹질에서 현저히 감소하였다. CCK-8투여시, 시상하부와 흑질에서의 TH-immunoreactive neuron의 수는 굶긴 쥐에 비하여 증가하였다. 이상의 실험 결과로 보아 음식물 섭취를 억제하는 작용이 있는 CCK-8은 시상하부의 도파민 신경계와 일부분 관련되어 있으며, 또한 시상하부와 흑질에 존재하는 TH-positive neuron은 음식물 섭취 행위에 중요한 역할이 있음을 시사하고 있다.

• 대한약침학회지
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• 제7권1호
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• pp.5-14
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• 2004

Acupuncture has fairly good weight-reducing effect in treating simple obesity due to the neuroendocrine regulation. In this study, the antiobesity effects of herbal acupuncture(HA) with Sang-hwang(phellinus linteus) at Fuai(SP16) were investigated in the rat fed on high-fat(HF) diet. Sang-hwang mushroom has been proven to have anti-carcinogenic effects and Sang-hwang extracts are highly effective in treatment and preventive treatment of AIDS, diabetes and high blood-pressure. To determine whether the Sang-hwang herbal acupuncture may have the anti-obesity effect, male Sprague-Dawley(4-wk-old) rats were fed a HF diet for 5 wk, which produced significant weight gain compared to rats were fed a normal diet, and then herbal acupuncture were treated for 3 wk in HF diet group. The body weight, food consumption, food effeciency ratio(FER), body fat mass, plasma nitric oxide(NO) were investigated in rats fed on normal diet, HF diet, and HF diet with HA(HF-diet-HA) groups. NO has been proposed to be involved in the regulation of food intake. In addition, the expression of appetite peptides such as orexigenic peptide neuropeptide Y(NPY) and the anorectic peptide cholecystokinin(CCK) were observed in the hypothalamus. HF-HA group reduced body weight gain, FER, body fat contents and NO concentration compared to HF diet group. The expression of NPY was reduced in arcuate nucleus(ARC), and CCK was increased in the paraventricular nucleus(PVN) after treatment of HA. In conclusion, Sang-hwang HA reduced adipocity, plasma NO and hypothalamic NPY, but increased CCK expression in the HF dietinduced obesity rat, therefore HA may have anti-obesity action through regulating body weight and appetite peptide of the central nervous system.

• Animal cells and systems
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• 제15권3호
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• pp.203-210
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• 2011

In the present study, we examined the effects of caffeine on food intake and body weight, and pro-opiomelanocortin (POMC) and agouti-related protein (AgRP) expression in the hypothalamus. Rats were administered intraperitoneally with 100 mg/kg caffeine (a high, non-toxic dose) or saline during the light phase. Intraperitoneal administration of caffeine induced a significant reduction in food intake and body weight 12 hr after treatment. In addition, POMC expression was significantly increased and AgRP expression was decreased in the arcuate nucleus (Arc) after caffeine treatment. These results demonstrate that administration of caffeine up-regulates POMC expression and down-regulates AgRP expression in the Arc, suggesting that the activation of the hypothalamic POMC neurons and inhibition of the AgRP neurons might play a role in the regulation of food intake and body weight by caffeine.