Some cells change the type of neurotransmitters they release depending on the circumstances, sometimes releasing up to five different kinds. But new work in the field has uncovered that neurons are not fixed when it comes to the chemicals they release.
Today, the majority of neuroscientists will tell you that most neurons release the same neurotransmitter from their axons-which is why you may see some neurons referred to as “dopaminergic” or “serotonergic,” releasing dopamine or serotonin, respectively. Eccles later revised Dale’s Law to say that specific neurons release a similar set of neurotransmitter types at their synapses, if not a single neurotransmitter. But as technologies and techniques in the field advanced, scientists saw that neurons can synthesize and release more than one type of neurotransmitter. This theory, called Dale’s Law, was suggested by Australian neurophysiologist and Nobel Laureate John Eccles based on the previous work of neuroscientist Henry Hallett Dale. When scientists first studied these powerful little neurochemicals, they believed each type of neuron released a single, unique neurotransmitter over its lifetime.
