生长激素释放肽-2对生长猪生长激素分泌模式的影响

Effects of GHRP-2 on the patterns of GH in growing pigs

为弄清生长激素释放肽-2（GHRP-2）对生长猪生长激素（GH）分泌模式的影响,选择25 kg体重的去势公猪,通过外科手术安装颈静脉插管,试验猪随机分为两组,每组4头,一组为对照,一组为处理组,处理组肌肉注射30μg/kg体重GH-RP-2,于注射后的0、15、30、45、60、90、120、180 min,以及6、9、12 h通过插管采取5 mL血样,分离血清,用放免法测定GH含量。结果显示血中GH的含量在处理组的30-90 min,与对照组存在极显著的差异（P〈0.01）,并在60 min达到分泌的峰值,120 min后回落到对照组水平。表明肌肉注射30μg/kg体重GHRP-2能够促进GH分泌,血中GH在30-90 min极显著地大于对照组,并在60 min达到分泌峰值。

Castrated male pigs at 25 kg/BW were selected and fixed with jugular vein catheter.Eight pigs were divided into two groups of 4 pigs each.In the first group,pigs were i.m injected with GHRP-2 at a dose of 30 μg/kg/BW.Five milliliter blood was collected at the 0,15,30,45,60,90,120,180 min and 6,9,12 hour after the injection,respectively.The serum GH was determined by radioimmunoassay.The result indicated that the GH levels in the treatment group were significantly increased at 30～90 min as compared to the controls （P〈0.01）. The GH Secretion peaked at 60 min and declined to control levels after 120 min. It concluded that GHRP-2 at a dose of 30 μg/kg/BW could promote the GH secretion, and the mechanisms underlying the effect of GHRP-2 on GH secretion required further investigations.