代谢综合征患者瘦素抵抗的研究

目的 :研究代谢综合征 (MS)患者瘦素抵抗的状况。　方法 :选取 5 0例MS患者 (MS组 )和 30例正常人 (正常对照组 ) ,分别测定体重指数 (BMI)、腰臀比 (WHR)、收缩压 (SBP)、舒张压 (DBP)、血清瘦素水平 (leptin)、空腹血糖(FPG)、空腹胰岛素 (FIns)、血清总胆固醇 (TC)、三酰甘油 (TG)、低密度脂蛋白胆固醇 (LDL C)、高密度脂蛋白胆固醇(HDL C)以及脂蛋白 (a)〔LP(a)〕 ,并计算HOMA胰岛素抵抗指数 (HOMA IR)。　结果 :与正常对照组相比 ,MS组血清瘦素水平显著上升 [(2 3.82± 1 5 .6 3) μg/Lvs(1 1 .2 0± 4 .70 ) μg/L ,P <0 .0 1 ],BMI、WHR、SBP、DBP、HOMA IR、TC、TG、LDL C、HDL C亦明显升高 ,而两组间LP(a)差异无显著性意义 (P >0 .0 5 )。　结论 :MS患者血清瘦素水平显著升高 ,可能由于该患者群存在一定程度的瘦素抵抗 ,使正常的脂肪 胰岛素轴反馈机制受到破坏、瘦素抑制胰岛素分泌的能力下降 ,从而导致MS的发生     

选择性动脉钙刺激静脉采血检测胰岛素定位胰岛素瘤的临床研究

目的 研究选择性动脉钙刺激静脉采血(ASVS)检测胰岛素值定位胰岛素瘤的临床应用价值。方法 对连续10例定性诊断为胰岛素瘤的患者术前行ASVS检查。选择性插管至胃十二指肠动脉、肠系膜上动脉、脾动脉近段及远段，分别快速注入葡萄糖酸钙0．3g激发，于激发前后不同时相经肝静脉采血测胰岛素值。计算不同激发值与基础值之比值，取比值最高者为峰比值，认定峰比值最高的动脉所供应的胰腺区域为肿瘤所在区域。结果 ASVS准确定位率为90％，优于B超(30％)、超声内镜(43％)、CT(70％)、MRI(78％)及选择性血管造影(20％)。本组仅2例患者主诉轻度头晕、胸闷。结论 ASVS在胰岛素瘤的定位中较其他影像学检查有更高的准确性，尤其适合于诊断和定位困难的病例。快速注入小剂量钙剂能安全有效地激发肿瘤细胞分泌胰岛素产生峰值。以胰大动脉为界区分脾动脉近段与远段分别激发有助于胰尾肿瘤的定位。     

Inhibitory effect of fluoride on the secretion of insulin

Summary The oral administration of sodium fluoride (NaF) (40 μmol/100 body weight [bw]) to fasting rats produced an immediate fall in insulin levels and the consequent increase in glycemia. These phenomena were observed with plasma fluoride concentrations 5–15 μM. Glycemia and insulin returned to normal levels within 4–5 hours, together with the washing out of fluoride from plasma and soft tissues. The insulin secretion of isolated Langerhans islets, perifused with solutions containing 5, 10, or 20 μM fluoride, was found to be significantly inhibited as a function of fluoride levels, both with basal and stimulatory concentrations of glucose. One hour after the intake of 60 mg of NaF, fasting human volunteers showed increased fluoride (5–15 μM) together with a significant fall of plasma insulin levels.     

前列腺素与糖尿病肾病关系的探讨

用放免法测定糖尿病肾病２６例、单纯糖尿病２４例和同年龄的健康对照者２５例血浆的血栓素Ｂ２（ＴＸＢ２）、６－酮前列腺素Ｆ１α（６－ｋ－ＰＧＦ１α）及空腹血糖（ＦＳＧ）、基础胰岛素（ＩＦ）、血肌酐（ＳＣｒ）水平。结果显示，糖尿病肾病组ＴＸＢ２明显高于对照组，６－ｋ－ＰＧＦ１α明显下降，ＳＣｒ与－ｋ－ＰＧＦ１α呈负相关，与ＴＸＢ２呈正相关，ＴＸＢ２／６－ｋ－ＰＧＦ１α与空腹血糖呈正相关，与内源胰岛素释放无关。     

Morphologische Wirkung von Adrenalin und Insulin auf Knochenkapillaren nach Rezeptorenblockade

In three groups of six mice each, the α- and β-receptors were blocked by phentolamine and propranolol. The mice in the three groups then received an intravenous bolus injection of saline solution, epinephrine, and insulin, respectively. Cortical bone capillaries from the tibia diaphysis were submitted to transmission electron microscopy (TEM). The lumen and endothelium were measured and the results compared. Significant changes were only noted in the endothelium after the administration of insulin. These findings suggest that there are also insulin receptors in bone. Furthermore, they support previous findings in similar studies with epinephrine.     

2型糖尿病患者胆结石发生的高危因素分析

目的：探讨2型糖尿病患者胆结石与高胰岛素、脂代谢紊乱的关系。方法：采用病例对照研究的方法，观察50例伴胆结石与60例不伴胆结石的2型糖尿病患者血清胰岛素、胰岛素敏感指数、C肽、血脂的变化。结果：发现伴胆结石患者的血清胰岛素、C肽、甘油三酯、胆固醇显著高于不伴胆结石组（P＜0．05），高密度脂蛋白、胰岛素敏感指数显著低于不伴胆结石组（P＜0．05），载脂蛋白－A1明显降低（P＜0．01），而两组低密度脂蛋白、脂蛋白－a、载脂蛋白－B1无差异。结论：高胰岛素血症、脂代谢异常可能中老年2型糖尿病患者胆结石 形成的高危因素。     

Reduced secretion of gastric inhibitory polypeptide in turner patients with impaired glucose tolerance

There is a well documented increase in the incidence of abnormal glucose tolerance in patients with Turner syndrome. To elucidate the pathophysiology of this phenomenon, we studied the serum concentrations of gastric inhibitory polypeptide (GIP) — as probably the most important hormonal factor of the entero-insular axis — in relation to impaired glucose tolerance in this syndrome. Oral glucose tolerance tests were performed in 12 Turner patients with simultaneous determination of plasma glucose, insulin and GIP. An impaired glucose tolerance (iGT) was found in four patients with a chronological age between 12.3 and 14.9 years. These patients were compared with found Turner patients of similar age and weight and a normal glucose tolerance (nGT). The highest insulin level occurred 90 min after stimulation in the patients with iGT compared to 30 min in the nGT group. Interestingly, the total areas under the insulin curves were not different. Stimulated plasma GIP concentrations and the areas under the GIP curves wer significantly lower in iGT compared to nGT patients. A disturbed entero-insular axis might contribute to the delayed — rather than diminished — release of insulin in patients with Turner syndrome and impaired glucose tolerance.Deceased February 21, 1987     

Ⅱ型糖尿病血浆PAI-1、t-PA检测的意义和结果评价

目的:通过对Ⅱ型糖尿病患者分组(伴血管病变组、胰岛素抵抗组、胰岛素抵抗伴血管病变组、Ⅱ型糖尿病组)检测PAI-1、t-PA抗原及活性,并计算抗原比和活性比,以评价各检测指标的临床价值。方法:采用ELISA法检测PAI-1及t-PA抗原,采用发色底物法检测PAl-1、t-PA活性。结果:189例标本总体患病组及分组后各组的PAI-1活性、t-PA活性及t-PA活性/PAI-1活性比值与正常对照组比较均有显著性差异(P<0.05)。患病组间除t-PA抗原,其余检测显示胰岛素抵抗组、胰岛素抵抗组伴血管病变组与Ⅱ型糖尿病组存在显著性差异(P<0.05)。结论:在上述检测指标中t-PA活性、PAI-1活性反映血管病变的发生较敏感,t PA/PAI-1的活性比值更具临床应用价值。     

Insulin binding to trophoblast plasma membranes and placental glycogen content in well-controlled gestational diabetic women treated with diet or insulin,in well-controlled overt diabetic patients and in healthy control subjects

Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·10⁹ l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects.     

Olfactory Absorption of Insulin to the Brain

A vast number of potent neuropharmaceuticals, many of which are peptides, are excluded from entry into the brain because of the highly selective blood-brain barrier. The fact that a number of drugs have been shown to be transported directly to the central nervous system following application to the olfactory region of the nose is therefore of major interest. In the present study, the feasibility of delivering peptides to the brain via the olfactory route was assessed using insulin as a model peptide. Systemic hyperinsulinemia induced by subcutaneous injection did not significantly reduce the amount of ¹²⁵I-insulin transported from the nose to the brain in vivo, which suggests that the impact of systemic absorption on drug transport is minimal. A linear relationship was seen between insulin accumulation in the brain and the dose applied, without any relevant saturation. Contrary to what was expected, both systemic and olfactory absorption of insulin was enhanced when the pH of the medium was near the isoelectric point. The amount absorbed to the brain was found to be linearly related to the net charge of the molecule (r = -0.61; n = 20). It was concluded that insulin gains access to the central nervous system from the olfactory region of the nose by a nonspecific pathway. The olfactory route may therefore become an important means to deliver peptides to the brain.