Pancreatic Islet Mass in Pregnancy - Pilot Study
试验速览
- 阶段
- 不适用
- 状态
- 终止
- 入组人数
- 12
- 试验地点
- 2
- 主要终点
- The documentation of Cpeptide in women with type 1 diabetes who are pregnant
研究概览
简要总结
Type 1 diabetic women have a decrease in insulin requirements during early pregnancy. Preliminary evidence suggests this decrease may be secondary to the regeneration of pancreatic B-cells during pregnancy During the second and third trimesters, insulin requirements in Type 1 diabetic women progressively increase until approximately 36 weeks gestation at which time there is a plateau, and frequently, a drop in insulin requirements. We hypothesize that there is regeneration of pancreatic islet cell mass in Type 1 diabetic women during pregnancy. In a cross-sectional study, we will use the acute insulin c-peptide response to arginine to determine if pancreatic islet mass increases at 12 and 36 weeks gestation. Type 1 diabetic women who are not pregnant, who are at 12 and 36 weeks gestation, and who are 6 weeks post-partum will undergo an intravenous arginine tolerance test following an overnight fast. If we find that there is regeneration of beta cells it opens the possibility that therapy may be directed to the same end for people with Type 1 diabetes.
详细描述
For the pilot phase of this study we will contact women with type 1 diabetes. The study will be explained and the subjects will be asked to sign an informed consent. Each subject will be asked to complete a brief medical history and lifestyle questionnaire.
Subjects will have blood samples taken for glucose and C-peptide and an intravenous arginine stimulation test. For the study tests, subjects will be asked to come to the Clinical Investigations Unit at the University of Alberta Hospital after an overnight fast only once during the study. The intravenous arginine test is a 10 minute test and does not cause hyperglycemia, an advantage over glucose in the setting of pregnancy.
Arginine infusion The intravenous arginine infusion test will be performed after an overnight fast greater than or equal to 8 hours. Subjects may drink water. For the Type 1 diabetic patients on insulin, long-acting insulin may be taken no less than 8 hours prior to the test; no food or short-acting insulin may be taken within 5 hours of the test. Lispro insulin should not be taken within 4 hours of the test.
On the morning of the test, an intravenous catheter, using a 20 gauge IV intercath, will be placed in an antecubital vein in one arm both for sampling and for infusion. Veins will be kept patent with an infusion of NaCl (0.9%) at 25 mL/hr throughout the test. The arm from which samples are obtained will be warmed to 55 C with a heating blanket to assist in the arterialization of the venous samples.
Baseline blood samples for glucose and C-peptide measurements will be drawn in a serum gel barrier tube at minus 10 and 0 minutes. An injection of 5 g of arginine (20 ml Sabex) diluted with 20 ml normal saline to equal 40 ml will be administered over 30 seconds, starting at time 0. The vein will immediately be flushed with 20mL normal saline. Blood samples for insulin and C-peptide will be drawn in barrier tubes at 2, 3, 4, 5, 7 and 10 minutes and serum will be separated and transferred into a cryogenic tube for analysis.
研究设计
- 研究类型
- Observational
- 观察模型
- Case Only
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •Signed informed consent
- •Females with Type 1 diabetes for at least 5 years
- •Diabetes onset < 21 years
- •Lean at diabetes onset
- •Insulin required from diagnosis
- •Willing to undergo intravenous arginine tolerance tests
排除标准
- •Inability to provide informed consent
- •Any medical condition that would preclude safe conduct of the intravenous arginine
- •A family history which includes three generations of family members with the diagnosis of diabetes mellitus
- •Women with elevated serum creatinine as arginine is excreted by the kidneys.
结局指标
主要结局
The documentation of Cpeptide in women with type 1 diabetes who are pregnant
时间窗: 1 year
次要结局
未报告次要终点
研究者
Edmond A Ryan
Professor
University of Alberta