• Clinical and Experimental Reproductive Medicine
• /
• 제23권3호
• /
• pp.269-275
• /
• 1996

Biosynthesis and secretion of anterior pituitary hormones are under the control of specific hypothalamic stimulatory and inhibitory factors. Among them, Growth Hormone Releasing Hormone (GHRH) is the major stimulator of pituitary somatotrophs activating GH gene expression and secretion. Human GHRH is a polypeptide of 44 amino acids initially isolated from pancreatic tumors, and the gene for the hypothalamic form of GHRH is organized into 5 exons spanning over 10 kilobases (kb) on genomic DNA and encodes a messenger RNA of 700-750 nucleotides. Several neuropeptides classically associated with the hypothalamus have been found in the extrahypothalamic regions, suggesting the existence of novel sources, targets and functions. GHRH-like immunoreactivity has been found in several peripheral sites, including placenta, testis, and ovary, indicating that GHRH may also have regulatory roles in peripheral reproductive organs. Furthermore, higher molecular weight forms of the GHRH transcripts were identified from these organs (1.75 kb in testis; 1.75 and >3 kb in ovary). These tissue-specific expression of GHRH gene suggest the existence of unique regulatory mechanism of GHRH expression and function in these organs. In fact, placenta-specific and testis-specific promoters for GHRH transcripts which are located in about 10 kb upstream region of hypothalamic promoter were reported. The use of unique promoters in extrahypothalamic sites could be refered in a different control of GHRH gene and different functions of the translated products in these tissues. Somatotrophs and lactotrophs have been thought to be derived from a common bipotential progenitor, the somatolactotrophs, which give origins to either phenotypes. Although the precise mechanism responsible for the lactotroph differentiation in the anterior pituitary gland has not been yet clalified, there are several candidators for the generation of lactotrophs. In human, the presence of GHRH peptides with different size from authentic hypothalamic form in the normal anterior pituitary and several types of adenoma were demonstrated. Recently our group found the existence of immunoreactive GHRH and its transcript from the normal rat anterior pituitary (gonadotroph> somatotroph> lactotroph), and the GHRH treatment evoked the increased proliferation rate of anterior pituitary cells in vitro. The transgenic mouse models clearly shown that GHRH or NGF overexpression by anterior pituitary cells induced development of pituitary hyperplasia and adenomas particularly GH-oma and prolactinoma. Taken together, we hypothesize that the pituitary GHRH could serve not only as a modulator of hormone secretion but as a paracrine or autocrine regulator of anterior pituitary cell proliferation and differentiation. Interestingly enough, the expression of Pit-1 homeobox gene (the POU class transcription factor) was confined to somatotrophs, lactotrophs and somatolactotrophs in which GHRH receptors are expressed commonly. Concerning the mechanism of somatolactotroph and lactotroph differentiation in the anterior pituitary, we have focused following two possibilities; (1) changes in the relative levels or interactions of both hypothalamic and intrapituitary factors such as dopamine, VIP, somatostatin, NGF and GHRH; (2) alterations of GHRH-GHRH receptor signaling and Pit-1 activity may be the cause of lactotroph differentiation or pituitary hyperplasia and adenoma formation. Extensive further studies will be necessary to solve these complicated questions.

• 한국발생생물학회지:발생과생식
• /
• 제8권2호
• /
• pp.91-97
• /
• 2004

본 연구는 임신한 생쥐에 DEHP의 투여가 자손의 번식특성과 혈액성분에 미치는 영향을 검토하였으며 그결과는 다음과 같다. 임신기에 DEHP의 투여가 웅성 자손의 체중, 번식기관 무게 및 정액 성상에 미치는 결과는 투여구간에 커다란 차이가 없었다. 임신기에 DEHP의 투여가 웅성 자손의 혈액 성상에 미치는 영향을 조사한 결과, WBC, HB, HT, MCH 및 albumin은 투여구간에 차이가 없었으나, RBC MCV, MCHC, PLT 및 total protein은 각 투여구간에 통계적으로 유의적인 차이가 나타났다. 임신기에 DEHP의 투여가 자성 자손의 체중, 자궁 및 오른쪽 난소의 무게에 미치는 영향을 조사한 결과, 각 투여구간에 커다란 차이가 없었지만, 왼쪽 난소의 무게는 10.0mg 투여구가 대조구와 0.5mg 투여구에 비해 통계적으로 유의하게 높은 무게를 나타냈다. 임신기에 DEHP의 투여가 자성 자손의 혈액성상에 미치는 영향을 조사한 결과, RBC, HB 및 HT는 각 투여구간에 커다란 차이가 없었다. 임신기에 DEHP의 투여가 자손의 정소, 난소 및 자궁의 조직에 미치는 영향을 조사한 결과,정소에서는 투여구간에 차이가 없었으며, 난소에서는 10.0mg 투여구가 여타구보다 많은 황체를 가지고 있었으며, 자궁에서는 대조구에 비해 DEHP의 투여농도가 증가할수록 자궁내막층이 감소했으며, 1.0mg 투여구와 10.0mg 투여구는 대조구에 비해 뚜렷한 자궁내막층의 감소가 있었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권1호
• /
• pp.77-82
• /
• 2014

The study aimed to evaluate the potential effects of feeding with phytase transgenic corn (PTC) on organ weight, serum biochemical parameters and nutrient digestibility, and to determine the fate of the transgenic DNA in laying hens. A total of 144 50-week-old laying hens were grouped randomly into 2 treatments, with 8 replicates per treatment and 9 hens per replicate. Each treatment group of hens was fed with diets containing 62.4% non-transgenic conventional corn (CC) or PTC for 16 weeks. The phytase activity for CC was 37 FTU/kg of DM, whereas the phytase activity for PTC was 8,980 FTU/kg of DM. We observed that feeding PTC to laying hens had no adverse effect on organ weight or serum biochemical parameters (p>0.05). A fragment of a poultry-specific ovalbumin gene (ov) was amplified from all tissues of hens showing that the DNA preparations were amenable to PCR amplification. Neither the corn-specific invertase gene (ivr) nor the transgenic phyA2 gene was detected in the breast muscle, leg muscle, ovary, oviduct and eggs. The digestibility data revealed no significant differences between the hens that received the CC- and PTC-based diets in the digestibility of DM, energy, nitrogen and calcium (p>0.05). Phosphorus digestibility of hens fed the PTC-based diet was greater than that of hens fed the CC-based diet (58.03% vs 47.42%, p<0.01). Based on these results, it was concluded that the PTC had no deleterious effects on the organ weight or serum biochemical parameters of the laying hens. No recombinant phyA2 gene was detected in muscle tissues and reproductive organs of laying hens. The novel plant phytase was efficacious in improving the phosphorus digestibility of laying hens.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권1호
• /
• pp.74-81
• /
• 2010

The effects of different levels of natural clay enterosorbent on the growth, nutrient availability, and genital organs of post-weaning female pigs fed with an addition of zearalenone (ZEA) were investigated in the study. A total of thirty-five post-weaning gilts ($L{\times}Y{\times}D$) with an average body weight of 12.36${\pm}$1.46 kg were used in the test. The gilts were raised individually in metabolism cages and fed a corn-soybean meal-whey basal diet with an addition of 0 or 1 mg/kg of ZEA for 24 d with four levels of natural clay enterosorbent added in the feed. The treatments were: i) control; ii) control+2.5 g/kg clay; iii) control+1 mg/kg ZEA; iv) control+1 mg/kg ZEA+1.25 g/kg clay; v) control+1 mg/kg ZEA+2.5 g/kg clay; vi) control+1 mg/kg ZEA+5.0 g/kg clay; vii) control+1 mg/kg ZEA +10 g/kg clay. Pigs fed diets contaminated with additional purified ZEA had significantly reduced apparent digestibility of crude protein (CP), gross energy (GE) and apparent metabolic rate of GE (ME/GE, p<0.05) without changes of net protein utilization (NPU, p>0.05). Final body weight, average daily gain (ADG), average daily feed intake (ADFI), vulva length, vulva width, vulva area, relative weights of genital organ and proliferative changes of the ovary tissues in gilts fed ZEA-contaminated diet were increased (p<0.05) compared to the gilts fed the control diet. Addition of natural clay enterosorbent in the ZEA-contaminated diet showed a positive protection effect on ZEA feeding, and the protection was increased linearly or quadratically as clay content increased. However, in pigs fed a diet with clay alone at 2.5 g/kg level there was no significant impact (p>0.05) on all the parameters as compared to the control. It is suggested that feeding ZEA at about 1.0 mg/kg for 24 days might result in a deleterious effect in pigs, and addition of 5 or 10 g clay enterosorbent per kg diet can effectively neutralize the detrimental effects of the ZEA feeding.

• Journal of Animal Science and Technology
• /
• 제62권4호
• /
• pp.521-532
• /
• 2020

The production performance of broiler breeder hens in response to different levels of total lysine during the early laying period was investigated. A total of 126 Ross 308 parent stock hens were offered one of seven dietary treatments formulating elevated contents of total lysine ranging from 0.55% to 0.79% (0.04 scale; 133 g of feed) from 23 to 29 weeks of age. Each treatment had six replicates with three birds per pen. Body weight was recorded triweekly and eggs were collected and weighted at 9:00 am daily. One hen from each pen was euthanized to collect blood samples and visceral organs were harvested and weighed. Egg production, egg weight and egg mass were lower (p < 0.05) in hens offered a diet containing 0.55% total lysine compared to those fed the diet containing higher total lysine. Hens offered a diet containing 0.71%, 0.75%, and 0.79% total lysine had greater (p = 0.008) egg production rate compared to those offered a diet containing lysine less than 0.71%. The number of total eggs produced tended to be greater (p = 0.083) in hens offered a diet containing 0.71 and 0.75% total lysine compared to the other treatments. The number of settable egg production was higher (p < 0.001) in hens offered a diet contacting 0.79% total lysine compared to those fed the diet containing lower levels of total lysine. The relative weights of oviduct and ovary were lower (p < 0.05) in hens offered a diet containing 0.59% total lysine compared to the other treatments. No difference found in body weight, the number of total eggs, double-yolk eggs and abnormal shell eggs among the treatments. The urea nitrogen, estradiol-17 beta and progesterone in plasma were not affected by treatments. Based on linear- and quadratic-plateau models, total lysine requirements for egg production, settable egg production and egg mass at the early laying period were to be 0.73%, 0.77%, and 0.71%, respectively. Modern broiler breeder hens likely require higher total lysine than NRC recommendation in a diet for enhancing productivity during the early-laying period.

• Toxicological Research
• /
• 제25권4호
• /
• pp.209-216
• /
• 2009

We have recently reported that the continuous exposure of rats to a concrete building environment under cool temperatures had adverse effects on general health parameters and embryo-fetal development. This study examined to compare the potential effects of concrete and wood building environments on pregnant dams and embryo-fetal development in rats. Groups of 10 mated females were exposed to polycarbonate (control), concrete, or wood cages from gestational days (GD) 0 to 20 under cool temperatures $(11.9\sim12.3^{\circ}C)$. All the females underwent a caesarean section on GD 20, and their fetuses were examined for any morphological abnormalities. The temperatures in the cages were similar in all groups but the relative humidity in the concrete and wood groups were higher than in the control group. The concentration of volatile organic compounds in the wood group was higher than in the control group. In the concrete group, maternal effects manifested as an increase in the incidence of clinical signs, a lower body weight, and a decrease in the thymus and ovary weights. Developmental effects included increased post-implantation loss and decreased litter size. Infrared thermal analysis showed that the skin temperature of the rats in the concrete group was lower than that in the control group. In contrast, there were no exposure-related adverse effects on the maternal and developmental parameters in the wood group. Overall, the exposure of pregnant rats to a concrete building environment under cool temperatures has adverse effects on the clinical signs, body weight, skin temperature, organ weight, and embryo-fetal development. On the other hand, exposure to a wood building environment does not have any adverse effects in rats.

• 한국가금학회지
• /
• 제35권4호
• /
• pp.375-380
• /
• 2009

본 시험은 비절식 강제 환우 가 산란계의 장기 비율의 변화 및 혈액 성상에 미치는 영향을 알아보고자 60주령 Leghorn종 400수를 공시하여 34주간 실시하였다. 처리구는 관행적으로 절식한 대조구(C), 옥수수 단일사료 급여(T1), 밀기울 단일 사료 급여(T2) 및 알팔파 단일 사료를 급여(T3)한 4처리로서, 처리구당 5반복, 반복당 20수씩 철제 케이지에 완전임의 배치하였다. 시험결과, 생체중 대비 장기 비율은 환우 개시시 난소는 $2.03{\sim}2.86%$, 난관은 $2.51{\sim}3.47%$로 처리구간에 유의차를 보이지 않았으며, 환우 종료시에는 난소의 경우 $0.25{\sim}0.41%$로서 차이가 없었으나, 난관은 대조구, T1구, T2 구 및 T3구가 각각 1.15%, 0.80%, 0.46% 및 0.89%로서 T2구가 대조구, T3구보다 유의적으로 낮았다(P<0.05). 50% 산란시 난소는 $2.19{\sim}2.60%$, 난관은 $3.00{\sim}3.50%$였으며, 산란피크시에 난소의 경우 2.65{\sim}3.01%, 난관은 $3.25{\sim}3.65%$로서 절식과 비절식에 따른 처리간에 차이가 나타나지 않았다. 혈액성상에서 Cholesterol은 환우 개시시 $179.8{\sim}245.7\;mg/dL$로서 처리간에 차이가 없었고, 환우 종료시에는 대조구 353.6, T1구 229.1, T2구 261.8 및 T3구 300.6 mg/dL로서 T1구가 대조구 및 T3구보다 유의적으로 낮았으며(P<0.05), 시산시에는 $228.1{\sim}271.8\;mg/dL$, 50% 산란시에는 $236.5{\sim}284.8\;mg/dL$로서 처리간에 차이가 없었다. 산란 피크시에는 대조구, T1구, T2구 및 T3구가 각각 324.1, 591.6, 363.0 및 315.6 mg/dL로서 T1구가 다른 처리구에 비하여 유의적으로 높았다(P<0.05).

• Toxicological Research
• /
• 제4권1호
• /
• pp.55-84
• /
• 1988

azinphos-methyl을 S.D.랫트에 투여하여 기형이 유발되는지의 여부와 태아의 기관형성 및 자궁내에서 태아의 발달에 미치는 영향을 알아보기 위하여 무처치의 negative control군, 수도물을 경구투여한 sham control군, 이미 기형효과가 있는 것으로 알려진 aspirin투여의 positive control군, 그리고 azinphosmethyl 0.094 mg/kg, 0.4 mg/kg 및 1.5mg/kg 투여군으로 나누어 각군 30마리씩으로, 임신 6~15일 사이에 경구투여한 결과는 다음과 같다. 즉, 모체의 체중증가율은 임신 7~14일, 즉 약물투여기에 aspirin 투여군과 azinphos-methyl 1.5mg/kg 투여군에서 현저한 감소를 보였다(p<0.01). 모체의 장기무게는 azinphos-methyl 1.5mg/kg 투여군에서 간장의 절대무게비가 유의성(p<0.05) 있는 감소를 보였으며, 신장의 절대 및 상대무게비는 aspirin군에서 (p<0.05, p<0.01), 또 난소의 절대 및 상대무게비는 aspirin 투여군(p<0.01)과 azinphos-methyl 전처치군(p<0.05)에서 유의성 있게 증가하였다. 모체 간장의 단백질량은 aspirin과 azinphos-methyl 1.5mg/kg 투여군에서 현저히 감소되었다(p<0.01). 모체의 배아와 태자에 대한 관찰 결과 azinphos-methyl 1.5mg/kg 투여군에서 암수의 비율에 있어 현저하게 증가(p<0.01) 했으며, 체중은 aspirin과 azinphos-methyl 1.5mg/kg 투여군에서 고도의 유의성(p<0.01) 있게 감소하였고, azinphos-methyl 0.4 mg/kg 투여군에서도 현저하게 감소하였다(p<0.05). 그리고 미숙태자와 흡수태자는 aspirin군에서, 죽은 태자수는 azinphos-methyl 1.5mg/kg 투여군에서 유의성 있게 증가하였다(p<0.05, p<0.01). 태자의 장기에서 나타난 기형은 aspirin과 azinphos-methyl 1.5mg/kg 투여군 공히 횡경막에서 횡격막 천공, 두부에서 무안구증, olfactory bulb의 확장, 수두뇌, 그리고 3뇌실과 측뇌실의 결손, 심장에서 좌심실벽 위축, 심첨확장 등이 유의성(P<0.01, P<0.05) 있게 관찰되었으며, 특히 횡경막, 심장 및 안구등에 높은 기형발생율을 보였다. 또 태자의 골화지연은 두개골에서 후두골, 접형골, 구개, 흉골에서 4번째 흉골편, 검상돌기, 척추에서 경추, 흉추, 미추, 전${\cdot}$후지골, 중족골에서 관찰되었다. 한편, 자연 분만시킨 태자의 사망율은 azinphos-methyl 1.5mg/kg 투여군에서 negative control군에 비해 고도의 유의성(p<0.01) 있게 높음을 알 수 있었으며, 체중도 역시 현저하게(p<0.01) 감소하였고, 발육지표중 pivoting, 체모형성, 청각능력, 시각능력, 사지근육 발달정도 및 고환하강시기 등에서 고도의 유의성(p<0.01)이 관찰되었다.

• Toxicological Research
• /
• 제18권1호
• /
• pp.47-57
• /
• 2002

The subacute oral toxicity of 1-(4-methylpiperazinyl)-3-phenylisoquinoline (CWJ- a-5) was investigated in Sprague-Dawley (SD) rats. Five groups of 5 males and 5 females were orally administered at doses of 0, 37.5, 75, 150 and 200 mg/kg with CWJ-a-5 for 2 weeks. In clinical signs, Salivation was observed in the 75, 150 and 500 mg/kg male and female groups. Loss of fur was observed in the 500 mg/kg male and female group. Body weight were significantly decreased in the 150 and 500 mg/kg male groups and in the 500 mg/kg female group. Food consumption was significantly decreased in the 300 mg/kg male group. In serum biochemistry, total cholesterol and phospholipid were significantly increased in 500 mg/kg male and female group. Aspartate aminotransferase was significantly increased in the 500 mg/kg female group. In histopathological examination, vacuolar degeneration of renal tubules in the kidney, vacuolar degeneration of hepatocytes in the liver vacuolar degeneration of myocytes in the heart, vacuolar degeneration of histiocytes in the spleen and thymus, atrophy of seminiferous tubule and degeneration of germinal epithelium in the testis, vacuolar degeneration of corpus luteum, granulosa cell and theca cell in the ovary were observed in the 150 and 500 mg/kg male and female groups. Based on these results, the no observed adverse effect level (NOAEL) with CWJ-a-5 was considered to be 75 mg/kg and the absolute toxic dose was considered to be 150 mg/kg in this study

• 한국가축번식학회지
• /
• 제11권1호
• /
• pp.63-72
• /
• 1987

정자와 정장의 항체가 정상 및 면역가토의 과배란과 수정율에 미치는 영향을 알고자 시도된 실험결과는 다음과 같다. 1. 면역가토에서의 과배란처리에 따른 평균배란점은 정자와 정장처리구에서 각각 22.9와 25.3개로서 대조구의 41개보다 현저히 적었다(P<0.05). 2. 자둥무게와 난포크기는 처리구간에 유의적 차이가 없었으며 그러나 정자 및 정장면역 가토에서의 수정율은 각각 62.8%와 58.0%로서 대조구의 91.4%보다 현저히 낮았다.(P<0.05). 3. 가토정액을 정자 또는 정장항혈청과 혼합하여 인공수정시 수정율이 각각 5.6%와 16.0%로서 대조구보다 현저히 낮았다(P<0.05). 결론적으로 정자 또는 정장면역이 수정율에 현저하게 영향하는 것으로 나타났다.