Advances in Pain Research and Therapy. Volume 6. Neural Mechanisms of Pain

This volume should be of value to both students and researchers interested in pain. The twenty-one papers are organized in a roughly anatomical direction, beginning at the nociceptor level, then moving through the spinal cord to the brain. Kruger and Liebeskind have done an excellent job of organizing the papers so that each topic leads into the next. After an introduction by Kruger and an overview by Bonica, the first four papers, by Perl, LaMotte, Iggo et al., and Wall, discuss nociceptor physiology in the context of nociceptors, mechanoheat receptors, arthritic joints, and peripheral nerve injury response on acute and chronic pain. The next eight papers, on spinal mechanisms, emphasize descending modulation by the serotonergic dorsal raphe nucleus. Interactions between serotonergic input and local circuit enkephalinergic neurons are discussed, as well as heterogeneity among spinal enkephalinergic (or opiate) systems. Discussion of substance P is relatively infrequent. Both Ralston and Willis extensively discuss spinothalamic tract projections and modulation of spinothalamic tract neurons by peripheral receptors, brainstem, and cortex. Mayer and Watkins consider the selective activation of opiate versus non-opiate mediated analgesia by frontversus hindpaw foot shock. Similarly, Liebeskind's group finds selective activation of these two analgesic systems by high-stress intermittent foot shock as opposed to low-stress continuous foot shock. The final section of the volume is more clinically oriented. The first paper discusses treatment of chronic intractable pain by electrical stimulation of the periaqueductal gray. The remaining papers pertain to methods for classifying and measuring pain in animals and humans. Although this volume does not completely cover all areas of pain research, all the papers are of the highest quality from the leading scientists in the field. The contributions are readable, well written, and contain a low level of redundancy. As a collection of papers, this volume would provide an excellent text for a seminar on pain.