Kimmel J R, Pollock H G
Endocrinology. 1981 Nov;109(5):1693-9. doi: 10.1210/endo-109-5-1693.
The problem of the physiological function of pancreatic polypeptide (PP) has been approached by attempting to identify target organs. Avian PP (aPP) labeled with 125I at either the C-terminus (aPP-C) or the N-terminus (aPP-N) was injected into fasted chickens and allowed to circulate for 3-120 min. At the end of the equilibration period, the anesthetized bird was perfused first with saline, then with Buoin's solution. Samples of fixed tissue from various organs were collected, weighed, and counted. Control experiments consisted of coinjection of unlabeled aPP to compete for receptors. The rate of disappearance of aPP-N from plasma was greater than that of aPP-C. Binding of aPP-N by spleen, duodenum, ileum, pancreas, and bone marrow was markedly reduced by coinjection of unlabeled aPP. A similar but less marked reduction in binding was found in liver and proventriculus. aPP-C gave less conclusive results. The maximal competitive effect of unlabeled PP could be achieved in most cases with 30 microgram unlabeled aPP. It is concluded that pancreas, duodenum, ileum, spleen, and bone marrow, and probably liver and proventriculus, are target organs for aPP in the chicken and that the C-terminal region of aPP is involved in receptor binding.
通过尝试识别靶器官来研究胰多肽（PP）的生理功能问题。将用125I标记在C末端（aPP-C）或N末端（aPP-N）的禽胰多肽（aPP）注射到禁食的鸡体内，并使其循环3至120分钟。在平衡期结束时，先给麻醉的鸡灌注生理盐水，然后灌注布安氏溶液。收集来自各个器官的固定组织样本，称重并计数。对照实验包括同时注射未标记的aPP以竞争受体。aPP-N从血浆中的消失速率大于aPP-C。同时注射未标记的aPP可使脾脏、十二指肠、回肠、胰腺和骨髓对aPP-N的结合显著减少。在肝脏和腺胃中发现结合减少，但程度较轻。aPP-C的结果不太明确。在大多数情况下，30微克未标记的aPP就能达到未标记PP的最大竞争效果。结论是，胰腺、十二指肠、回肠、脾脏和骨髓，可能还有肝脏和腺胃，是鸡体内aPP的靶器官，并且aPP的C末端区域参与受体结合。
