Byrnes Elizabeth M
Department of Biomedical Sciences, Tufts University School of Veterinary Medicine, 200 Westboro Rd, North Grafton, MA 01536, USA.
Pharmacol Biochem Behav. 2005 Mar;80(3):445-51. doi: 10.1016/j.pbb.2004.12.011.
Opiate use in teenage populations has been increasing in recent years. The potential impact of exposure to high levels of opiates at a time when reproductive systems are maturing has not been well studied, especially in females. The present study used an animal model of adolescent opiate abuse in females to examine the potential impact of high levels of opiates during puberty on several reproductive parameters, including suckling-induced prolactin secretion. Two groups of juvenile female rats were administered increasing doses of morphine sulfate or saline (s.c.) from age 30-50 days, beginning with a dose of 2.5 mg/kg and achieving a maximal dose of 50 mg/kg. As adults, these females were mated and reared either their own or foster pups. On either postpartum day 5 or 10, following a 4 h separation, suckling-induced prolactin secretion was measured. In addition, on postpartum day 5 maternal behavior latencies were determined. The results demonstrate reduced suckling-induced prolactin secretion on postpartum day 5 in females previously exposed to morphine during pubertal development. These effects were observed in females rearing either their own or fostered pups. These effects were not due to any differences in maternal behavior latencies, as retrieval or crouching latencies were unaffected. In summary, chronic morphine exposure during puberty results in changes in the regulation of prolactin secretion during early lactation, which are observed several weeks after cessation of drug treatment. These data suggest that prior opiate use during puberty can continue to affect the regulation of prolactin secretion into adulthood.
近年来，青少年群体中阿片类药物的使用呈上升趋势。在生殖系统发育成熟阶段接触高水平阿片类药物的潜在影响尚未得到充分研究，尤其是在女性中。本研究使用雌性青少年阿片类药物滥用动物模型，来检验青春期高水平阿片类药物对包括哺乳诱导的催乳素分泌在内的几个生殖参数的潜在影响。两组幼年雌性大鼠从30至50日龄开始皮下注射递增剂量的硫酸吗啡或生理盐水，起始剂量为2.5毫克/千克，最大剂量达到50毫克/千克。成年后，这些雌性大鼠与自己的或寄养的幼崽进行交配并抚养。在产后第5天或第10天，经过4小时的分离后，测量哺乳诱导的催乳素分泌。此外，在产后第5天测定母性行为潜伏期。结果表明，青春期曾接触吗啡的雌性大鼠在产后第5天，其哺乳诱导的催乳素分泌减少。在抚养自己幼崽或寄养幼崽的雌性大鼠中均观察到了这些影响。这些影响并非由于母性行为潜伏期存在任何差异，因为找回幼崽或蹲伏潜伏期未受影响。总之，青春期慢性吗啡暴露会导致哺乳早期催乳素分泌调节发生变化，这种变化在药物治疗停止数周后仍可观察到。这些数据表明，青春期之前使用阿片类药物会持续影响成年期催乳素分泌的调节。
