Blass E M
Department of Psychology, Cornell University, USA.
Behav Neurosci. 1997 Feb;111(1):147-54. doi: 10.1037//0735-7044.111.1.147.
Antinociception was evaluated in 10-day-old rats while suckling or in contact with the mother. Testing occurred during, immediately after, or at 30 and 60 s following milk-induced hyperextension. Hyperextension-induced hypoalgesia terminated immediately with stretch cessation. For suckling rats, baseline escape levels were reacheived within 1 min. For contact rats, baseline levels were also manifest at 30 s but were elevated by 1 min. Sublingual infusions into the anterior portion of the mouth in rats that were either suckling or in contact caused a 20-25-s increase in escape latencies. For suckling rats, escape latencies returned to baseline levels immediately at infusion termination. For contact rats, latencies continued to be elevated for at least 5 min postinfusion. Thus, 3 classes of mother-infant interactions, contact, suckling, and hyperextension during milk letdown, cause varying degrees of hypoalgesia in 10-day-old rats.
在10日龄的大鼠哺乳或与母亲接触时评估其抗伤害感受。测试在乳汁引起的过度伸展期间、之后立即进行，或在过度伸展后30秒和60秒进行。伸展停止后，伸展诱导的痛觉减退立即终止。对于哺乳大鼠，在1分钟内恢复到基线逃避水平。对于接触大鼠，基线水平在30秒时也表现出来，但在1分钟时升高。对正在哺乳或接触的大鼠口腔前部进行舌下灌注，导致逃避潜伏期增加20 - 25秒。对于哺乳大鼠，灌注终止时逃避潜伏期立即恢复到基线水平。对于接触大鼠，灌注后潜伏期至少持续升高5分钟。因此，母婴之间的三类相互作用，即接触、哺乳和乳汁排出时的过度伸展，会在10日龄大鼠中引起不同程度的痛觉减退。
