Iki Katsumichi, Pour Parviz M
UNMC Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198-6805, USA.
J Histochem Cytochem. 2007 Feb;55(2):111-8. doi: 10.1369/jhc.6A7024.2006. Epub 2006 Sep 18.
There is a lack of agreement on the distribution of islet amyloid polypeptide (IAPP) in the pancreases of healthy and diabetic subjects. Therefore, a detailed morphometrical and immunohistochemical study was performed to obtain information on the distribution of cells expressing insulin, glucagon, somatostatin, pancreatic polypeptide (PP), and IAPP in the pancreases of non-diabetic (n=4) and diabetic individuals (n=6). In the non-diabetic cases, beta-cells contributed to approximately 64%, alpha-cells to 26%, delta-cells to 8%, PP cells to 0.3%, and IAPP cells to 34% of the islet cell population. The ratio of IAPP/insulin was approximately 1:2. In diabetic cases, beta-cells were decreased by 24%, and IAPP was decreased by 57%. The alpha- and delta-cells were increased by 40% and 58%, respectively. IAPP/insulin ratio was decreased by 41%. Thus, only 50% of the beta-cells in non-diabetics and only 30% in diabetics coexpressed IAPP. In diabetics, more delta-cells coexpressed IAPP than in non-diabetics. The results seem to argue against the notion that the secretion of IAPP is increased in diabetics. It is possible that an increase in somatostatin and glucagon plays a greater role in diabetes than IAPP.
关于健康受试者和糖尿病患者胰腺中胰岛淀粉样多肽（IAPP）的分布，目前尚无定论。因此，我们进行了一项详细的形态计量学和免疫组织化学研究，以获取非糖尿病患者（n = 4）和糖尿病患者（n = 6）胰腺中表达胰岛素、胰高血糖素、生长抑素、胰多肽（PP）和IAPP的细胞分布信息。在非糖尿病病例中，β细胞约占胰岛细胞总数的64%，α细胞占26%，δ细胞占8%，PP细胞占0.3%，IAPP细胞占34%。IAPP/胰岛素的比例约为1:2。在糖尿病病例中，β细胞减少了24%，IAPP减少了57%。α细胞和δ细胞分别增加了40%和58%。IAPP/胰岛素比例下降了41%。因此，非糖尿病患者中只有50%的β细胞和糖尿病患者中只有30%的β细胞共表达IAPP。在糖尿病患者中，共表达IAPP的δ细胞比非糖尿病患者更多。这些结果似乎与糖尿病患者中IAPP分泌增加的观点相悖。生长抑素和胰高血糖素的增加在糖尿病中可能比IAPP起更大的作用。
