Macphail R C, Farmer J D, Jarema K A, Chernoff N
Neurotoxicology Division, U.S. Environmental Protection Agency, 109 TW Alexander Drive, MD B105-03, Research Triangle Park, NC 27711, USA.
Neurotoxicol Teratol. 2005 Jul-Aug;27(4):593-8. doi: 10.1016/j.ntt.2005.05.004.
Anatoxin-a is a nicotinic agonist produced by several genera of cyanobacteria, and has caused numerous deaths of wildlife, livestock and domestic animals world-wide. Several studies in the literature have shown that exposure of mice and rats to nicotine early in development alters its effects when the rodents are subsequently challenged with nicotine. We therefore determined the effect of nicotine on the motor activity of adult mice that had been exposed prenatally to anatoxin-a. Pregnant CD-1 mice received either saline vehicle or one of two doses of (+/-) anatoxin-a (125, 200 microg/kg), i.p., on GD13-17. As adults (8 months), control mice of both genders were used to determine the effect of nicotine (0, 0.1, 0.3, 1.0 or 3.0 mg/kg, s.c.) on motor activity measured for 30-min in a photocell device. Under these conditions, nicotine produced dose-related decreases in both horizontal and vertical activity, with an ED50 estimated to be 0.65 mg/kg. Next, additional control mice and mice exposed prenatally to anatoxin-a received the nicotine ED50 and saline vehicle, in a counterbalanced fashion, with one week separating treatments. Nicotine decreased both horizontal and vertical activity in all mice, regardless of prenatal anatoxin-a treatment. Thus, no enduring effects of prenatal anatoxin-a were obtained in adult mice following nicotine challenge.
anatoxin-a是由几种蓝细菌属产生的一种烟碱激动剂，已在全球范围内导致大量野生动物、家畜和宠物死亡。文献中的几项研究表明，在发育早期将小鼠和大鼠暴露于尼古丁会改变其随后受到尼古丁刺激时的反应。因此，我们确定了尼古丁对产前暴露于anatoxin-a的成年小鼠运动活动的影响。怀孕的CD-1小鼠在GD13-17时腹腔注射生理盐水或两种剂量（125、200微克/千克）的（+/-）anatoxin-a之一。成年后（8个月），使用两种性别的对照小鼠来确定尼古丁（0、0.1、0.3、1.0或3.0毫克/千克，皮下注射）对在光电管装置中测量30分钟的运动活动的影响。在这些条件下，尼古丁使水平和垂直活动均出现剂量相关的下降，估计ED50为0.65毫克/千克。接下来，另外的对照小鼠和产前暴露于anatoxin-a的小鼠以平衡的方式接受尼古丁ED50和生理盐水，两次处理间隔一周。无论产前是否接受anatoxin-a处理，尼古丁均降低了所有小鼠的水平和垂直活动。因此，在尼古丁刺激后，成年小鼠未获得产前anatoxin-a的持久影响。
