Carlsson P O, Palm F, Andersson A, Liss P
Department of Medical Cell Biology, Uppsala University, Sweden.
Diabetes. 2001 Mar;50(3):489-95. doi: 10.2337/diabetes.50.3.489.
In this study, we syngeneically transplanted islets to three different implantation sites of diabetic and nondiabetic rats, then 9-12 weeks later we measured the blood perfusion and compared the tissue partial pressure of oxygen (PO2) levels of these transplanted islets to endogenous islets. Modified Clark microelectrodes (outer tip diameter 2-6 microm) were used for the oxygen tension measurements, and islet transplant blood perfusion was recorded by laser-Doppler flowmetry (probe diameter 0.45 mm). The islet graft blood perfusion was similar in all islet grafts, irrespective of the implantation site. In comparison, the three implantation organs (the kidney cortex, liver, and spleen) differed markedly in their blood perfusion. There were no differences in islet graft blood perfusion between diabetic and nondiabetic recipients. Within native pancreatic islets, the mean PO2 was approximately 40 mmHg; however, all transplanted islets had a mean PO2 of approximately 5 mmHg. The oxygen tension of the grafts did not differ among the implantation sites. In diabetic recipients, an even lower PO2 level was recorded in the islet transplants. We conclude that the choice of implantation site seems less important than intrinsic properties of the transplanted islets with regard to the degree of revascularization and concomitant blood perfusion. Furthermore, the mean PO2 level in islets implanted to the kidney, liver, and spleen was markedly decreased at all three implantation sites when compared with native islets, especially in diabetic recipients. These results are suggestive of an insufficient oxygenization of revascularized transplanted islets, irrespective of the implantation site.
在本研究中，我们将同基因胰岛移植到糖尿病和非糖尿病大鼠的三个不同植入部位，然后在9至12周后测量血液灌注，并将这些移植胰岛的组织氧分压（PO2）水平与内源性胰岛进行比较。使用改良的克拉克微电极（外尖端直径2 - 6微米）进行氧张力测量，通过激光多普勒血流仪（探头直径0.45毫米）记录胰岛移植的血液灌注。所有胰岛移植物的胰岛移植血液灌注相似，与植入部位无关。相比之下，三个植入器官（肾皮质、肝脏和脾脏）的血液灌注有显著差异。糖尿病和非糖尿病受体的胰岛移植血液灌注没有差异。在天然胰腺胰岛中，平均PO2约为40 mmHg；然而，所有移植胰岛的平均PO2约为5 mmHg。移植物的氧张力在植入部位之间没有差异。在糖尿病受体中，胰岛移植中记录到的PO2水平更低。我们得出结论，就血管再生程度和伴随的血液灌注而言，植入部位的选择似乎不如移植胰岛的内在特性重要。此外，与天然胰岛相比，植入到肾脏、肝脏和脾脏的胰岛在所有三个植入部位的平均PO2水平均显著降低，尤其是在糖尿病受体中。这些结果表明，无论植入部位如何，血管再生的移植胰岛的氧合作用不足。
