ABSTRACT
This article reviews the difficulty in defining pain and chronic pain syndromes. A basic review of nerve transmission as related to chronic pain syndromes is provided. Three general chronic pain categories are developed, and the major pain syndromes of each category are explored. The etiology, transmission, and treatment of each are discussed.
Subject(s)
Pain , Synaptic Transmission , Chronic Disease , Humans , Nociceptors/physiopathology , Pain/classification , Pain/etiology , Pain/physiopathology , Pain Management , Pain Measurement , SyndromeABSTRACT
The retrograde transport-HRP-immunocytochemical technique was employed to ascertain if the periaqueductal gray-raphe magnus projection arises from neurons containing somatostatin, neurotensin, serotonin or cholecystokinin. Following HRP injections into the raphe magnus (NRM) double-labeled cells containing HRP reaction product and somatostatin-, neurotensin- or serotonin-like immunoreactivity were identified in the midbrain periaqueductal gray (PAG). No cholecystokinin-like immunoreactive double-labeled neurons were found in the PAG. These results indicate that the PAG-NRM pathway contains somatostatin, neurotensin and serotonin but not cholecystokinin.
Subject(s)
Brain Stem/anatomy & histology , Cholecystokinin/metabolism , Neurotensin/metabolism , Periaqueductal Gray/anatomy & histology , Raphe Nuclei/anatomy & histology , Serotonin/metabolism , Somatostatin/metabolism , Animals , Immunoenzyme Techniques , Male , Neural Pathways/anatomy & histology , Neurons/ultrastructure , Nociceptors/anatomy & histology , Rats , Rats, Inbred StrainsABSTRACT
Cells with possible dual projections to both spinal trigeminal nuclei were identified in the rat brainstem following separate injections of different retrogradely transported markers into the right and left spinal trigeminal nucleus. The greatest number of double-labeled cells was located in the nucleus reticularis gigantocellularis. Several double-marked cells were also observed in the nucleus raphe magnus, the nucleus paragigantocellularis and the periaqueductal gray. These results suggest that some cells in the above brainstem nuclei may have a bilateral modulating effect on the spinal trigeminal nuclei.
Subject(s)
Brain Stem/physiology , Neurons/physiology , Spinal Cord/physiology , Trigeminal Nuclei/physiology , Animals , Axonal Transport , Brain Stem/anatomy & histology , Efferent Pathways/physiology , Fluorescent Dyes , Functional Laterality , Rats , Spinal Cord/anatomy & histology , Trigeminal Nuclei/anatomy & histologyABSTRACT
Through the use of radiative collisions, sometimes called photon-induced collisions, and the autoionizing properties of N(2)*(X, nu), a system using He-N(2) is presented as a high-efficiency (~15%) ultraviolet laser amplifier when an intense (>1 MW/cm(2)) photon field, tuned to the transition of interest, is directed into the system. The model is described using rate-equation analysis, and calculations are presented to describe this system.
