Nociception and Acute Pain: Neurotransmitters and Neuromodulators

As if the anatomical architecture of the nociceptive and pain system were not complex enough, a huge variety of additional neurotransmitters, neuromodulators and hormones adds on to it. This new dimension will be treated here. The review is structured from two complementary angles: first, the anatomical and neurophysiological perspective, covering key structures from peripheral nociceptors to central brain regions such as the cortex, basal ganglia, hypothalamus, and various brainstem nuclei; and second, the molecular and biochemical perspective, outlining the array of neuroactive substances – including neuropeptides, classical neurotransmitters, and neuromodulators – involved in nociception and acute pain modulation. In selected sections, appropriate case reports are presented to illustrate specific mechanisms or phenomena, and at the end, some clinical syndromes are mentioned to link basic concepts with clinical relevance. Sub-cellular processes and therapeutic approaches are beyond the scope of this review.