十二指肠内输注淀粉水解物和酪蛋白期间，外源性生长抑素和半胱胺对绵羊门静脉引流内脏和肝脏净营养物质通量的影响。

Effects of exogenous somatostatin and cysteamine on net nutrient flux across the portal-drained viscera and liver of sheep during intraduodenal infusion of starch hydrolysate and casein.

作者信息

McLeod K R, Bauer M L, Harmon D L, Reynolds C K, Mitchell G E

机构信息

Department of Animal Sciences, University of Kentucky, Lexington 40546-0215, USA.

出版信息

J Anim Sci. 1997 Nov;75(11):3026-37. doi: 10.2527/1997.75113026x.

DOI:10.2527/1997.75113026x

PMID:9374319

Abstract

We used eight Polypay wethers (36 +/- .6 kg BW) fitted with hepatic portal, hepatic venous, mesenteric arterial and venous, and duodenal catheters in a crossover design experiment to determine the influence of somatostatin (SRIF) on splanchnic metabolism. Each crossover period consisted of 14 d, with net flux of nutrients and hormones (venoarterial differences x blood flow) measured on d 14. Before flux measurements, wethers received an i.v. dose (0 h) of either 0 (vehicle) or 50 mg x kg BW(-1) x 10 min(-1) cysteamine (CSH, SRIF-depleting agent) followed by a continuous duodenal infusion (h 10 to 22) of a starch hydrolysate-casein solution. Six sets of arterial, portal, and hepatic blood samples were obtained (h 12 to 16), after which a primed (10 microg), continuous jugular infusion of SRIF-14 (5.0 microg x kg BW(-1) x h(-1)) was initiated and sampling protocol repeated (h 18 to 22). Cysteamine administration increased (P < .01, vs control) portal and hepatic blood flow in the absence of exogenous SRIF (CSH x SRIF, P < .01). Net portal-drained viscera (PDV) release of glucose, alpha-amino N, ammonia N, beta-hydroxybutyrate, and oxygen consumption were decreased (P < or = .10) and lactate release increased (P = .005) during SRIF infusion. The CSH increased (P < .05) PDV release of beta-hydroxybutyrate and insulin and increased (P = .09, CSH alone vs control) net release of glucose in the absence of exogenous SRIF. Exogenous SRIF increased (P = .10) and CSH decreased (P = .09) net hepatic glucose output, whereas liver oxygen consumption was decreased (P = .04) with exogenous SRIF and increased (P = .01) with CSH. Net total splanchnic alpha-amino N release and oxygen consumption were decreased (P < .10) with exogenous SRIF, but CSH increased (P < .05) insulin release and oxygen consumption. These data provide initial evidence for a regulatory involvement of SRIF in visceral metabolism in ruminants.

摘要

我们使用了八只波利佩伊阉羊（体重36±0.6千克），在交叉设计实验中给它们安装了肝门静脉、肝静脉、肠系膜动脉和静脉以及十二指肠导管，以确定生长抑素（SRIF）对内脏代谢的影响。每个交叉期为14天，在第14天测量营养物质和激素的净通量（动静脉差值×血流量）。在通量测量前，阉羊静脉注射一剂（0小时）0（赋形剂）或50毫克/千克体重×10分钟⁻¹的半胱胺（CSH，生长抑素耗竭剂），随后在十二指肠持续输注（10至22小时）淀粉水解物-酪蛋白溶液。在12至16小时采集六组动脉、门静脉和肝血样本，之后开始颈静脉首剂（10微克）、持续输注SRIF-14（5.0微克/千克体重×小时⁻¹），并重复采样方案（18至22小时）。在没有外源性SRIF的情况下，给予半胱胺可增加（P<0.01，与对照组相比）门静脉和肝血流量（CSH×SRIF，P<0.01）。在输注SRIF期间，门静脉引流内脏（PDV）的葡萄糖、α-氨基氮、氨氮、β-羟基丁酸盐释放和氧消耗减少（P≤0.10），乳酸释放增加（P=0.005）。在没有外源性SRIF的情况下，CSH增加（P<0.05）PDV的β-羟基丁酸盐和胰岛素释放，并增加（P=0.09，单独使用CSH与对照组相比）葡萄糖的净释放。外源性SRIF增加（P=0.10），CSH减少（P=0.09）肝脏葡萄糖净输出，而外源性SRIF使肝脏氧消耗减少（P=0.04），CSH使其增加（P=0.01）。外源性SRIF使总内脏α-氨基氮净释放和氧消耗减少（P<0.10），但CSH增加（P<0.05）胰岛素释放和氧消耗。这些数据为生长抑素参与反刍动物内脏代谢调节提供了初步证据。