Armstrong J D, Esbenshade K L, Johnson J L, Coffey M T, Heimer E, Campbell R M, Mowles T, Felix A
Dept. of Anim. Sci., North Carolina State Univ., Raleigh 27695-7621.
J Anim Sci. 1990 Feb;68(2):427-34. doi: 10.2527/1990.682427x.
Cyclic gilts (96 +/- 1 kg) were used to determine the effect of active immunization against growth hormone-releasing factor GRF(1-29)-NH2 on concentrations of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). Gilts were immunized against GRF conjugated to human serum albumin (GRF-HSA, n = 5) or HSA alone at 180 d of age (wk 0). Booster doses were administered at wk 9 and 13. Seven days after the second booster (wk 14), blood samples were collected at 15-min intervals for 6 h before feeding and 30, 60, 120, 180 and 240 min after feeding. Eight days after the second booster, all gilts were administered a GRF analog, [desNH2Tyr1,Ala15]-GRF(1-29)-NH2, followed by an opioid agonist, FK33-824. Blood samples were collected at 15-min intervals from -30 to 240 min after injection. Immunization against GRF-HSA resulted in antibody titers, expressed as dilution required to bind 50% of [125I]GRF, ranging from 1:11,000 to 1:60,000 (wk 11 and 14); binding was not detectable or was less than 50% at 1:100 in HSA gilts (P less than .05). Episodic release of GH was abolished by immunization against GRF-HSA (P less than .05). Mean GH was decreased (P less than .07), but basal GH concentrations were not altered (P greater than .15) by immunization against GRF-HSA. Serum concentrations of IGF-1 were similar at wk 0, but concentrations were lower in GRF-HSA than in HSA gilts (P less than .05) at wk 14.(ABSTRACT TRUNCATED AT 250 WORDS)
选用体重96±1千克的经产母猪来确定主动免疫生长激素释放因子GRF(1-29)-NH2对生长激素(GH)和胰岛素样生长因子1(IGF-1)浓度的影响。在180日龄（第0周）时，对母猪进行针对与人血清白蛋白偶联的GRF（GRF-HSA，n = 5）或仅针对人血清白蛋白的免疫。在第9周和第13周给予加强剂量。在第二次加强免疫后7天（第14周），在喂食前6小时每隔15分钟采集血样，并在喂食后30、60、120、180和240分钟采集血样。在第二次加强免疫后8天，给所有母猪注射一种GRF类似物[desNH2Tyr1,Ala15]-GRF(1-29)-NH2，随后注射一种阿片样物质激动剂FK33-824。在注射后-30至240分钟每隔15分钟采集血样。针对GRF-HSA的免疫导致抗体滴度（以结合50%[125I]GRF所需的稀释度表示）在1:11,000至1:60,000之间（第11周和第14周）；在人血清白蛋白组的母猪中，1:100时未检测到结合或结合率低于50%（P<0.05）。针对GRF-HSA的免疫消除了GH的脉冲式释放（P<0.05）。针对GRF-HSA的免疫使平均GH降低（P<0.07），但基础GH浓度未改变（P>0.15）。第0周时IGF-1的血清浓度相似，但在第14周时，GRF-HSA组的浓度低于人血清白蛋白组（P<0.05）。（摘要截短至250字）
