Neurons communicate with one another through the release of neuro-transmitters, chemical substances that transmit nerve impulses between nerve cells. Numerous types of neurotransmitters have been identified. Some of these transmitters act to excite neurons, while others inhibit neuronal activity. The particular type of transmitter is synthesized within the cell body of the neuron, travels along the axon, and is released into the space between neurons, known as the synapse.
Among the most prominent neurotransmitters involved in the excitation of neurons is acetylcholine. The same transmitter bridges the junctions between nerves and skeletal muscles as well as glandular tissues in the body. In the brain, acetylcholine bridges the synapses between neurons throughout the central nervous system. The amino acids glutamic acid and aspartic acid are also known to be involved in excitation of some neurons within the brain. The neurotransmitter serotonin is released mainly within the brain stem, where it appears to regulate activities such as sleep, moods, and body temperature.
Certain neurotransmitters serve in the inhibition of neuronal activity. The most common of these is gamma-aminobutyric acid (GABA), found primarily in the diencephalon region of the brain. Here GABA acts to reduce the activity within the region. Antianxiety drugs such as valium or lib-rium appear to work by enhancing the activity of GABA, resulting in the relaxation of skeletal muscles. Antidepression compounds such as Prozac and Zoloft appear to function through blockage of serotonin uptake by neurons.
Was this article helpful?