1·There are at least two classes of these receptors, which have been designated A1 and A2.
这些受体至少有两类，分别被命名为 A1 和 A2。
2·From signals sent by the receptors, the brain understands smells as complex spatial patterns.
通过受体发出的信号，大脑将气味理解为复杂的空间图案。
3·The higher their capacity to bind at the receptors, the higher their ability to stimulate locomotion.
它们结合受体的能力越强，它们刺激运动的能力就越强。
4·The milk of many mammals contains cannabinoids, substances that are known to stimulate certain receptors in the brain.
许多哺乳动物的奶含有大麻素，这种物质可以刺激大脑中的某些受体。
5·Like many other agents that affect neuron firing, adenosine must first bind to specific receptors on neuronal membranes.
像许多其他影响神经元放电的物质一样，腺苷必须首先与神经元膜上的特定受体结合。