One is that repeated exposure to nicotine may cause nicotinic receptors to become less sensitive to nicotine.

一种理论认，反复使用尼古丁可能导致烟碱体对尼古丁敏感性下降。

Alright, so in this case, the patient's B cells inappropriately make antibodies that bind to nicotinic acetylcholine receptors on the muscle cells.

好了，在这种情况下，患者B细胞产生了错误抗体，该抗体和肌肉细胞中N胆碱体相结合。

Another theory is that neurons may remove nicotinic receptors from the cell wall in a process called down-regulation, leaving fewer receptors available for binding.

另一理论认，神经元会主动减少细胞壁上烟碱体，这一过程也体下调，从而减少可供结合体数量。

COREY ALLARD: They didn't resemble known sensory  receptors instead they're most closely related to a family of receptors called  nicotinic acetylcholine receptors.

COREY ALLARD：像已知感觉体，相反，与烟碱乙酰胆碱体体家族关系最密切。

Myasthenia gravis is a type II hypersensitivity disorder where the body produces antibodies that most commonly target nicotinic acetylcholine receptors on the surface of muscle cells.

重症肌无力是一种II型超敏反应，身体产生抗体，常见靶点肌肉细胞表面N胆碱体抗体。

First you've got your motor neurons that release the neurotransmitter acetylcholine at the neuromuscular junction, which then binds to nicotinic acetylcholine receptors on muscle cell membranes.

首先，你运动神经元在神经肌肉接头处释放神经递质乙酰胆碱（ACh），然后与肌肉细胞膜上N胆碱体相结合。

The upper motor neuron releases acetylcholine from its axon terminal knobs and these are received by nicotinic receptors on the alpha motor neuron.

上运动神经元从轴突末端释放乙酰胆碱，作用于α运动神经元上烟碱体。

There are also medications that act on nicotinic receptors like buproprion and partial nicotine receptor agonists like varenicline which help reduce withdrawal symptoms and prevent relapse.

还有一些药物可以作用于烟碱体，如盐酸安他非酮，以及烟碱体部分激动剂，如瓦伦尼克林等，可以帮助减轻戒断综合征效应，防止复发。

The psychoactive effects of nicotine are related to the locations of nicotinic receptors in the brain and the exact neurotransmitters that are released when the receptors are stimulated.

尼古丁兴奋作用与烟碱体在脑中位置以及体激活所释放具体神经递质有关。

Once nicotine is absorbed into the bloodstream, it binds to a type of acetylcholine receptor, called a nicotinic acetylcholine receptor - also called a nicotinic receptor - which is found throughout the body and brain.

一旦尼古丁进入血液循环，就会和一种乙酰胆碱体结合，也烟碱型乙酰胆碱体或烟碱体；这类体广泛分布于身体和大脑中。

VOICEOVER: Nicotinic acetylcholine  receptors are found throughout the nervous system of many different animals but  usually they detect neurotransmitters within the body and are involved with things  like controlling muscle contractions.

画外音：烟碱型乙酰胆碱体存在于许多同动物神经系统中，但通常检测体内神经递质，并参与控制肌肉收缩等活动。

So nicotine, which is in e-cigarettes, for example, binds to a receptor called the nicotinic acetylcholine receptor, which plays a key role in the functioning of almost all organ systems in the human body.

例如，电子烟中尼古丁会与一种叫做烟碱型乙酰胆碱体体结合，这种体在人体几乎所有器官系统功能中起着关键作用。

In the central nervous system, nicotinic receptors are on pre-synaptic axon terminals of neurons, and when nicotine binds to them, it triggers the release of neurotransmitters like dopamine, acetylcholine, and glutamate, which is why it's considered an acetylcholine agonist.

在中枢神经系统中，烟碱体分布于突触前神经元轴突末端，当尼古丁与体结合后，会触发多巴胺、乙酰胆碱、谷氨酸盐等神经递质释放，因此尼古丁被认是一种乙酰胆碱体兴奋剂。