肥胖抑制素对大鼠胰腺腺泡和胰腺小叶淀粉酶分泌的影响

Effects of obestatin on amylase release of pancreatic acinar cells and lobules of rats

目的研究不同剂量肥胖抑制素（Obestatin）对大鼠离体胰腺腺泡及胰腺小叶淀粉酶分泌的影响。方法体外分离大鼠胰腺腺泡，与不同浓度Obestatin（0、0．1、1、10、30nmol／L）共培养1h；另一组加Obestatin30min后加入100pmol／L的胆囊收缩素（CCK-8）继续培养30min。分离含有胰腺内神经末端、胰岛细胞及外分泌细胞的胰腺小叶，与不同浓度Obestatin共培养30min；另一组加Obestatin同时加75mmol／LKC1共培养30rain。测定培养液及细胞或胰腺小叶组织内淀粉酶含量，计算淀粉酶分泌率。结果0、0．1、1、10、30nmol／LObestatin不影响胰腺腺泡细胞淀粉酶分泌率[（3．48±1．44）％、（3．70±1．39）％、（3．36±1．24）％、（3．86±1．41）％、（4．54±2．01）％]。CCK-能显著刺激腺泡细胞的淀粉酶分泌率[（13．844-2．63）％比（3．48±1．44）％，P〈0．05]，但0．1、1、10nmol／LObestatin对CCK-8诱导的胰腺腺泡淀粉酶分泌无显著性影响[（14．55±1．70）％、（13．79±1．81）％、（14．39±1．12）％]。Obestatin（0．1、1、10、30nmol／L）不影响胰腺小叶淀粉酶分泌率。KC1可显著刺激胰腺小叶淀粉酶分泌率[为对照组的（1．84±0．29）倍，P〈0．05]，但Obestatin对KC1诱导的胰腺小叶淀粉酶分泌无显著影响[为对照组的（2．01±0．30）、（1．894-0．41）、（1．744-0．14）、（1．88±0．33）倍]。结论Obestatin对体外培养的大鼠胰腺腺泡细胞及胰腺小叶淀粉酶分泌率无显著影响，也不能阻断或协同CCK-8和KC1对胰腺淀粉酶分泌的促进作用。

Objective To investigate the effects of different doses of obestatin on amylase secretion of pancreatic acinar and lobules of rats in vitro. Methods Pancreatic acinar cells of rats were separated in vitro and incubated with different doses of obestatin （0, 0.1 , 1,10, 30 nmol/L） for 1 h, another group of pancreatic acinar ceils was incubated with obestatin for 30 min, then was incubated with 100 pmol/L CCK-8 for another 30 min. Pancreatic lobules, which containing intrapancreatic nerve terminals and islets, were prepared and were incubated with different concentrations of obestatin for 30 min at 37℃ with or without 75 mmol/L KC1. Amylase levels in the supernatants, acinar cells and pancreatic lobules were calculated as a percentage of total amylase content. Results Obestatin （0, 0.1, 1, 10, 30 nmol/L） produced no significant change in basal amylase release of acinar cells [ （3.48 ± 1.44） %, （3.70 ± 1.39） %, （ 3.36 ± 1.24） %, （ 3.86 ± 1.41 ） %, （4.54 ± 2.01 ） % ]. CCK-8 significantly increased amylase release of acinar cells [ （ 13.84 ± 2.63 ） % vs （3.48 ± 1.44 ） %, P 〈 0.05 ], but obestatin （ 0.1, 1, 10 nmol/L） has no effect on the amylase release induced by CCK-8 [ （14.55 ±1.7）%, （13.79 ±1.81）%, （14.39 ±1.12）% ]. Obestatin （0.1, 1, 10,30 nmol/L） did not affect the amylase release of pancreatic lobule. KC1 significantly increased amylase release, which was （ 1.84 ± 0.29 ） folds higher than that of control group （ P 〈 0.05）, but obestatin has no effect on the amylase release induced by KC1, which were （2.01 ± 0.30）, （ 1.89 ± 0.41 ）, （ 1.74 ±0.14）, （ 1.88 ± 0.33） folds higher than those of control group. Conclusions Exogenous obestatin has no effects on pancreatic exocrine of acinar cells and lobules of rats in vitro and cannot block or assist the increased amylase release induced by CCK-8 or KC1.