• Animal cells and systems
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• 제13권1호
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• pp.17-23
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• 2009

In previous studies, we found that Annexin I (Anx I) was co-secreted with insulin in response to glucose, and that extracellular Anx I stimulated the release of insulin via the Anx I binding site in rat pancreatic islets and the &-cell line. However, the role that Anx I plays in the insulin secretion was not established. Therefore, in this study, we evaluated the insulin secretion pattern in response to Anx I and the involvement of the cytoskeleton or PKC in Anx Istimulated insulin secretion in MIN6N8a cells. The peak time of insulin secretion in response to Anx I treatment corresponded with the second phase insulin secretion by glucose in the perifused pseudoislets. In addition, Anx I-stimulated insulin secretion was not affect by readily releasable pool depletion. Taken together, these findings indicate that Anx I treatment was associated with movement of the reserve pool of insulin. Furthermore, Anx I-stimulated insulin secretion was attenuated by treatment with a microfilament inhibitor, cytochalasin B, as well as by PKC down regulation. These results indicate that Anx I may be a regulator of second phase insulin secretion.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.144-148
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• 1997

Insulin secretory response to various calcium concentrations was investigated in 10- to 12-week old male lean and obese Zucker rats using an in vitro pancreatic perfusion procedure. There was no significant difference in insulin secretion response to low, medium, and high calcium concentrations in the lean rat. However, the obese rat shows a characteristics of hypersecretion of insulin. The obese rat pancreas perfused with the low calcium concentration released as low insulin as the lean rat. When perfused with the medium calcium concentration, th obese rat pancreas released twice as much insulin as the lean rat. eh hypersecretory phenomenon was also seen in the obese rat pancreas perfused with the high calcium concentration during the first phase of erfusion period, but his phenomenon was gradually diminished during he second phase of perfusion period. These results indicate that there may be a selective insulin secretory response to the extracellular calcium in he obese Zucker rat pancreas.

• The Korean Journal of Physiology
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• 제10권2호
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• pp.29-37
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• 1976

Effect of furosemide administration on glucose tolerance, insulin-and HGH response following parenteral glucose loading was studied in healthy subjects. Effects of potassium or calcium on the furosemide induced changes were also observed in the same subjects. Furosemide administration resulted in a considerable reduction in the magnitude and duration of insulin response although no obvious changes were observed in glucose disappearance from the circulation. Oral potassium or calcium supplement to the furosemide treated subjects showed a reversion toward normal of the insulin response. The author suggested that a decreased endogenous insulin production resulting from the potassium and/or calcium depletion is responsible for the changes observed. In those subjects who receive parenteral nutrition if administration of furosemide is essential, it should be supplemented by potassium and/or calcium.

• Asian-Australasian Journal of Animal Sciences
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• 제20권10호
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• pp.1575-1579
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• 2007

The glucose tolerance and pancreatic insulin secretion response to glucose in sheep fed on germinated sorghum grain were determined using an intravenous glucose load. Twelve male Thin Tail sheep (an Indonesian native sheep, 12 months old and 14.8 kg average body weight) were divided randomly into sorghum grain-based (S), germinated sorghum grain-based (G) and maize grain-based (C) diets. Sheep were maintained at the same daily intake levels of metabolizable energy and crude protein in the diets throughout the experimental period. After two months of the experimental conditions, each diet group was subjected to an intravenous glucose load experiment in which five doses of glucose (0, 10, 20, 40 and 80 mg/kg BW) were injected to estimate the rate of glucose removal from blood and the pancreatic insulin secretion response. For each sheep and each glucose load dose, the incremental blood serum glucose and insulin concentrations above pre-injection concentration were calculated as serum glucose and insulin response areas. At all glucose doses, sheep fed on S diet had a greater (p<0.05) glucose response area compared to those of sheep fed on G and C diets. Likewise at all glucose doses, the insulin response area was smaller (p<0.05) in sheep fed on S diet than in sheep fed on G and C diets. The glucose and insulin response areas in sheep fed on G and C diets differed slightly. It was concluded that the portion of maize grain in the ruminant ration could be substituted by germinated sorghum grain.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.795-801
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• 2007

Patients with Type I diabetes mellitus have been treated with porcine insulin for several decades and pigs have recently been deemed an ideal source of microencapsulated islet cells for clinical xenotransplantation. In this study, neonatal pigs were anesthetized and sacrificed prior to a pancreatectomy. Islet cells were isolated from pancreas via collagenase digestion. Islet cells were separated and collected by hand under microscopic guidance. These cells were suspended in 1.4% sodium alginate solution and encapsulated by dropping them into 1.1% calcium chloride solution and in which the round gel in size was 250-400 ${\mu}m$ in diameter. Viability of the microencapsulated islet cells cultured in medium at $37^{\circ}C$ was assessed by MTT assay. Furthermore, insulin released in response to glucose challenge was investigated using an enzyme-linked immunosorbent assay. Secretion of insulin was low in response to the basal glucose solution (4.4 mM) in medium and was significantly higher in response to the high glucose solution (16.7 mM). The viability of microencapsulated islet cells did not differ significantly over a period of 7 days; that is, the increasing pattern of insulin concentration in the culture medium after glucose stimulation interval day was similar throughout the 7 days cultivation. In summary, experimental evidences indicated that the effects of alginate-microencapsulation prolonged survival of the neonatal porcine islets in vitro cultures and the insulin response to glucose of the islets was maintained.

• 한국축산시설환경학회지
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• 제3권1호
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• pp.1-12
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• 1997

This study was conducted to investigate the combined effects of VFA composition of rumen fluid and heat exposure (30${\pm}$2$^{\circ}C$) on the general clinical view and insulin secretory response to glucose in sheep. The total infusion of nutrients was examined in sheep via the technique of continuous alimentation. Four adult Suffolk sheep fitted with a permanent ruminal cannula and a simple T-shaped duodenal cannula were used. A peristaltic pump was used to infuse the solutions of volatile fatty acid triglycerides (VFA-TG) consisting of 70 triacetin : 20 tripropionin : 10 tributyrin (low propionin division: LP) and 50 triacetin : 40 tripropionin : 10 tributyrin (high propionin division: HP) on the basis of energy and minerals into the rumen, and casein solution into the duodenum. The effects of heat exposure and type of the levels of VFA-TG solutions on the insulin secretory response to glucose in sheep were investigated by using hyperglycemic clamp (HGC) technique. The results obtained are summarized as follows: 1. During the heat exposure (latter half of the infusion period), respiration rate, heart rate and rectal temperature increased (P＜0.01, P＜0.01, P＜0.05), but the levels of VFA-TG solutions (LP and HP division) did not affect the general clinical view except for the heart rate. 2. In the HGC technique, glucose infusion rate (GIR) and mean plasma insulin increments (MPII) tended to be ower in the heat exposure than in the thermoneutral environment, but no significant difference was found among the treatments. GIR and MPII remained unchanged between the levels of VFA-TG solutions. 3. In the HGC technique, ratio of MPII to GIR (MPII/GIR) which represents pancreatic ${\beta}$-cell response to glucose stimulation remained unchanged among the treatments.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.806-812
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• 2003

Attempts have been made to establish relationship between the response to ACTH challenge in female calves, growth and first lactation performance. A total of 19 Holstein calves weighing 100 kg i. v. were given 0.50 IU of ACTH/kg $BW^{.75}$ (EXACTHIN inj., Richter G., Budapest) at 60 days of age. Serial blood samples were taken at times 0, 0.5, 1, 2, 3, 4 and 5 hours and analyzed for cortisol, glucose insulin and FFA levels. From challenge series the area under the curve from time of administration and the following 5 h were calculated. Negative, and mostly loose relationship between response to ACTH challenge for cortisol, insulin, or FFA and ADWG during growth have been established (p>0.05) with positive one for glucose. Bivariate coefficients of correlation varied within the range from -0.35 to 0.15. Estimations reveal negative correlation between the length of first lactation and cortisol or insulin (r=-0.80, p<0.001 and r=-0.45, p<0.10, resp.) Close association between cortisol or insulin and actual first lactation milk yield was found (r=-0.48, p<0.10; r=-0.64, p<0.01, resp.). Close relationship between the response to ACTH challenge and milk protein yield was present only for insulin (r=-0.59, p<0.05).

• Journal of Yeungnam Medical Science
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• 제12권2호
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• pp.319-330
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• 1995

임신시 발생하는 인슐린 저항성과 인슐린 분비 증가의 기전을 규명하기 위하여 Sprague-Dawley 종 암컷 흰쥐를 이용하여 정맥당부하 검사와 호르몬 및 지방 대사물질과 조직에서의 인슐린 수용체 결합, 당원질 합성효소를 분석한 결과를 요약하면 다음과 같다. 정맥당부하검사에서 임신군에서 전체적인 곡선이 대조군에 비하여 아래에 위치하였다. 그러나 당부하시 인슐린 분비는 현저히 증가하였으며 혈당에 대한 비(${\mu}U/mg$)로 비교하여 임신군에서 $56.9{\pm}8.9$였고 대조군에서 $23.6{\pm}2.8$로서 인슐린 저항성을 확인할 수 있었다. 인슐린 분비반응의 증가는 태반 호르몬인 progesterone의 증가와 강한 상관관계를 나타내었다. 당부하검사후 당원질 (mg/100mg tissue)은 골격근(soleus)에서는 임신군과 대조군간에 유의한 차이가 없었으나 간조직에서는 임신군에서 $4.7{\pm}0.9$으로 대조군의 $9.9{\pm}1.3$에 비하여 통계적으로 유의하게 감소하였다. 당원질로 합성된 $^{14}C$-glucose의 활동도도 마찬가지로 골격근에서는 임신군과 대조군간에 유의한 차이가 없었으나 간조직에서는 현저한 감소를 보였다. 당원질 합성 효소(glycogen synthase)는 골격근에서는 대조군이 높았고 간장조직에서는 임신군이 높았으나 유의한 차이는 없었다. 당부하검사후 간장조직의 crude membrane에서의 인슐린-인슐린 수용체 결합반응에서는 두 군 사이에 유의한 차이가 없었다. 이상의 결과로 보아 정상임신흰쥐에서 인슐린 저항성이 발생하였으나 인슐린 분비의 현저한 증가로 내당능의 감소는 나타나지 않았으며 인슐린의 분비증가는 progesterone의 증가와 상관관계가 있었다. 인슐린 저항성은 간에서 가장 현저하게 나타났으며 그 원인은 인슐린 수용체의 결합과정보다는 수용체 전 과정이거나 수용체 후 과정일 것으로 추정된다.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.361-370
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• 2004

The discovery of insulin receptor substrate (IRS) proteins and their role to link cell surface receptors to the intracellular signaling cascades is a key step to understanding insulin and insulin-like growth factor (IGF) action. Moreover, IRS-proteins coordinate signals from the insulin and IGF receptor tyrosine kinases with those generated by proinflammatory cytokines and nutrients. The IRS2-branch of the insulin/IGF signaling cascade has an important role in both peripheral insulin response and pancreatic $\beta$-cell growth and function. Dysregulation of IRS2 signaling in mice causes the failure of compensatory hyperinsulinemia during peripheral insulin resistance. IRS protein signaling is down regulated by serine phosphorylation or protea-some-mediated degradation, which might be an important mechanism of insulin resistance during acute injury and infection, or chronic stress associated with aging or obesity. Under-standing the regulation and signaling by IRS1 and IRS2 in cell growth, metabolism and survival will reveal new strategies to prevent or cure diabetes and other metabolic diseases.

• 한국식품영양과학회지
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• 제20권4호
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• pp.293-299
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• 1991

쌀과 보리의 조리형태가 혈당과 혈청 insulin에 미치는 영향을 알다 보기 위하여 건강한 성인에게 정제 당질인 dextrose와 전분원으로 쌀과 보리를 밥과 죽 형태로 급여했다. 당질부하량은 50g 당질함량으로 계산하였고, 식후 혈청 glucose와 insulin반응을 3시간에 걸쳐 측정하였다. 그 결과 dextrose와 쌀죽 섭취군은 식후 혈당과 insulin반응이 유사하였고. 보리죽과 쌀밥 섭취군은 중정도였으며, 보리밥 섭취군이 가장 낮았다. 전분원에 따라 비교했을 때 쌀은 보리보다 높은 반응을 나타냈으며, 쌀과 보리를 죽 형태로 섭취했을 때가 밥으로 섭취했을 때보다 더욱 유의하게 높은 반응을 나타냈다. 이러한 결과는 당질의 종류뿐만 아니라 조리 형태는 당대사 반응을 결정짓는 주요한 인자임을 제시하고 있다.