Matozaki T, Sakamoto C, Nagao M, Baba S
Second Department of Internal Medicine, Kobe University School of Medicine, Japan.
Horm Metab Res. 1988 Mar;20(3):141-4. doi: 10.1055/s-2007-1010778.
Pretreatment of pancreatic acini with vasoactive intestinal peptide (VIP) or secretin for 120 min reduced subsequent [125I-Tyr1]somatostatin binding to membranes prepared from these acini, with a maximally reduced binding being 79.2% or 77.4% of control, respectively. In addition, exogenously added cyclic AMP derivatives or a phosphodiesterase inhibitor mimicked the effect of VIP or secretin. Scatchard analysis of [125I-Tyr1]somatostatin binding demonstrated that the decrease in the labeled somatostatin binding induced by VIP or dibutyryl cyclic AMP (dbcAMP) pretreatment was due to the decrease in the maximum binding capacity without a significant change in the binding affinity. The effect of simultaneous pretreatment of acini with VIP and carbamylcholine (carbachol) on subsequent labeled somatostatin binding appeared to be almost equal to the calculated additive value for each peptide. Results obtained, therefore, indicate that the binding of somatostatin to its receptors in the pancreas may be regulated via two functionally distinct pathways.
用血管活性肠肽（VIP）或促胰液素对胰腺腺泡进行120分钟的预处理，会降低随后[125I - 酪氨酸1]生长抑素与从这些腺泡制备的膜的结合，最大结合减少量分别为对照的79.2%或77.4%。此外，外源性添加的环磷酸腺苷衍生物或磷酸二酯酶抑制剂模拟了VIP或促胰液素的作用。对[125I - 酪氨酸1]生长抑素结合的Scatchard分析表明，VIP或二丁酰环磷腺苷（dbcAMP）预处理诱导的标记生长抑素结合减少是由于最大结合能力的降低，而结合亲和力没有显著变化。同时用VIP和氨甲酰胆碱（卡巴胆碱）对腺泡进行预处理对随后标记生长抑素结合的影响似乎几乎等于每种肽的计算相加值。因此，所得结果表明，生长抑素与其在胰腺中的受体的结合可能通过两条功能不同的途径进行调节。
