Gibbs M E
Pharmacol Biochem Behav. 1976 Jun;4(6):703-7. doi: 10.1016/0091-3057(76)90223-9.
Amphetamine overcomes the amnesia caused by cycloheximide (CXM) provided it is administered closely following the learning trial. In day-old chickens with one trial passive avoidance learning, there is a short-term, labile memory existing for 90 min following training under the influence of CXM. Amphetamine has been shown to keep the memory at precisely the level exhibited by the labile, cycloheximide-resistant memory trace at the time of injection. Norepinephrine, methoxamine (an alpha adrenergic stimulant) and isoprenaline (a beta adrenergic stimulant) each mimic the amphetamine effect in CXM-pretreated chickens. That the action of amphetamine could be due to its release of norepinephrine is supported by the finding that it could be blocked by both alpha adrenergic (piperoxane) and beta adrenergic antagonists (propranolol). It has been suggested that this labile memory trace depends on the functioning of a sodium pump. Norepinephrine may be modulating memory formation by an action on the sodium pump since in preliminary biochemical assays norepinephrine stimulated the sodium pump (Na+/K+ ATPase) activity in chicken forebrain total homogenate.
如果在学习试验后紧接着给予苯丙胺，它可以克服环己酰亚胺（CXM）引起的失忆。在一日龄雏鸡进行一次被动回避学习试验后，在CXM的影响下，训练后会存在一种持续90分钟的短期不稳定记忆。已证明苯丙胺能使记忆精确保持在注射时不稳定的、抗环己酰亚胺的记忆痕迹所表现出的水平。去甲肾上腺素、甲氧明（一种α肾上腺素能兴奋剂）和异丙肾上腺素（一种β肾上腺素能兴奋剂）在经CXM预处理的雏鸡中均能模拟苯丙胺的作用。苯丙胺的作用可能是由于其释放去甲肾上腺素，这一观点得到了以下发现的支持：它可被α肾上腺素能拮抗剂（哌氧环烷）和β肾上腺素能拮抗剂（普萘洛尔）阻断。有人提出这种不稳定的记忆痕迹依赖于钠泵的功能。去甲肾上腺素可能通过作用于钠泵来调节记忆形成，因为在初步生化试验中，去甲肾上腺素刺激了鸡前脑全匀浆中的钠泵（Na+/K+ ATP酶）活性。
