Hughes R A
Physiol Behav. 1982 Jul;29(1):67-71. doi: 10.1016/0031-9384(82)90367-5.
A series of three experiments examined the effects of atropine, scopolamine, and their methyl analogs on tonic immobility in chickens. The first experiment demonstrated significant attenuation of immobility duration by atropine and scopolamine. Methyl atropine and methyl scopolamine attenuated immobility duration but did so significantly less than equivalent amounts of atropine and scopolamine. Experiments 2 and 3 examined effects of atropine, methyl atropine, scopolamine, and methyl scopolamine on immobility duration as a function of posthatch age. In these experiments atropine and scopolamine attenuated TI duration at each test age examined. The methyl analogs attenuated TI duration only at the youngest age (7-days posthatch) and failed to do so at 14-days posthatch or older. These age-dependent differences between the tertiary and quaternary compounds were attributed to blood-brain-barrier development. In Experiments 2 and 3 immobility duration increased with increased posthatch age. Scopolamine prevented the age-related increase but atropine did not. This difference is discussed in terms of fear arousal.
一系列三项实验研究了阿托品、东莨菪碱及其甲基类似物对鸡强直静止的影响。第一项实验表明，阿托品和东莨菪碱可显著缩短静止持续时间。甲基阿托品和甲基东莨菪碱也能缩短静止持续时间，但效果明显不如等量的阿托品和东莨菪碱。实验2和实验3研究了阿托品、甲基阿托品、东莨菪碱和甲基东莨菪碱对静止持续时间的影响，该影响是孵化后年龄的函数。在这些实验中，阿托品和东莨菪碱在每个测试年龄都能缩短强直静止持续时间。甲基类似物仅在最年幼的年龄（孵化后7天）能缩短强直静止持续时间，在孵化后14天及更大年龄则无效。叔胺类和季铵类化合物之间的这些年龄依赖性差异归因于血脑屏障的发育。在实验2和实验3中，静止持续时间随着孵化后年龄的增加而增加。东莨菪碱可阻止与年龄相关的增加，但阿托品则不能。从恐惧唤起的角度讨论了这种差异。
