My OperaRising transmission of pain
Sunday, April 26, 2009 9:40:33 AM
Notsitseptivnye fibers are sent to the spinal cord and cranial nerves, in the case of spinal nerves, they penetrate into the spinal cord within the dorsal (posterior) roots. Sensory dorsal root fibers innerviruyut a certain segment of the body (dermatitis) (Figure 21.3).
In the spinal cord notsitseptivnye fiber ends in the dorsal horn gray matter. The cells of the spinal cord gray matter to construct a series of plates (laminae) (Fig. 21.4). Dorsal horn is composed of six layers of cells (1 - 6), have three layers - in the ventral horn (7 - 9). Tenth layer cells are concentrated around the central canal. Layer 2, which, as we have seen, occupies an important place in notsitseptivnyh ways, called yellow substance (substantia gelatinosa). These layers of cells in which cells are abundant in contact with other layers as short axons or dendrites, difficult to distinguish on the slices, cooked in conventional histopathological methods.
If you inject of horseradish peroxidase in sensory fibers in the periphery, it is transferred to aksoplazmaticheskim shocks in the central end. Thus can be traced organization of spinal gray matter. In general, the larger diameter fibers, the more it penetrates the gray matter, ie, large fibers of muscle spindles 1a (see ch. Kinesthesia), in the end plate 6. In contrast, small notsitseptivnye C-fiber end, mainly in the plate 2, and several large Adelta - in plates 1 and 5, Fig. 21.4 shows that, in addition to C-and Adelta-innervation in the ways of conducting the pain, present and the larger diameter fibers - A? and A? terminating in plate 4. We understand the importance of this when we consider the "gate theory. From the dorsal horn gray matter of spinal cord fibers that carry information to the supreme notsitseptivnuyu departments of central nervous system, divided in three white matter tract. STT (Spin-talamichesky tract) are most important. It begins in plates 1 and 5, and immediately becomes the ventro-lateral (front-lateral) segment kontrlateralnoy hand and sent to the thalamus. CPT (spin-reticular tract) is slightly dorsal (retrad) from the STT, and some fibers do not pass on the opposite side of the spinal brain. Trakt sends a branch in the reticular formation, as well as in the thalamus. Notsitseptivnye neurons plates 1 and 5 are projected in the SMT (the spin-mezentsefalichesky tract), the path which is similar to STT and SRT, but which ends in the gray matter surrounding Sylvia plumbing (aqueductus Sylvii) middle cerebral (PCA periakveduktalnoe gray matter) and in the reticular formation of secondary brain. In addition, small cells zhelatinoznoy Substance send processes to the small distance up and down on the surface of the spinal cord, consisting of tract Lissauera, there is serious evidence that the spinal plates brain, there are short intersegmentnye connection notsitseptivnyh cells. Thus, in addition to the three main notsitseptivnyh paths available and polisinaptichnsky ascending path. Notsitseptivnaya information after switch to thalamus, secondary brain reticular formation, and so goes further in the overlying sections of brain. However, in Unlike the special sensory cortex are not available in the specialized area of primary notsitseptsii. Most of the information gets into somestezicheskuyu cortex, but much of it is distributed in the brain diffusely.
pain
In the spinal cord notsitseptivnye fiber ends in the dorsal horn gray matter. The cells of the spinal cord gray matter to construct a series of plates (laminae) (Fig. 21.4). Dorsal horn is composed of six layers of cells (1 - 6), have three layers - in the ventral horn (7 - 9). Tenth layer cells are concentrated around the central canal. Layer 2, which, as we have seen, occupies an important place in notsitseptivnyh ways, called yellow substance (substantia gelatinosa). These layers of cells in which cells are abundant in contact with other layers as short axons or dendrites, difficult to distinguish on the slices, cooked in conventional histopathological methods.
If you inject of horseradish peroxidase in sensory fibers in the periphery, it is transferred to aksoplazmaticheskim shocks in the central end. Thus can be traced organization of spinal gray matter. In general, the larger diameter fibers, the more it penetrates the gray matter, ie, large fibers of muscle spindles 1a (see ch. Kinesthesia), in the end plate 6. In contrast, small notsitseptivnye C-fiber end, mainly in the plate 2, and several large Adelta - in plates 1 and 5, Fig. 21.4 shows that, in addition to C-and Adelta-innervation in the ways of conducting the pain, present and the larger diameter fibers - A? and A? terminating in plate 4. We understand the importance of this when we consider the "gate theory. From the dorsal horn gray matter of spinal cord fibers that carry information to the supreme notsitseptivnuyu departments of central nervous system, divided in three white matter tract. STT (Spin-talamichesky tract) are most important. It begins in plates 1 and 5, and immediately becomes the ventro-lateral (front-lateral) segment kontrlateralnoy hand and sent to the thalamus. CPT (spin-reticular tract) is slightly dorsal (retrad) from the STT, and some fibers do not pass on the opposite side of the spinal brain. Trakt sends a branch in the reticular formation, as well as in the thalamus. Notsitseptivnye neurons plates 1 and 5 are projected in the SMT (the spin-mezentsefalichesky tract), the path which is similar to STT and SRT, but which ends in the gray matter surrounding Sylvia plumbing (aqueductus Sylvii) middle cerebral (PCA periakveduktalnoe gray matter) and in the reticular formation of secondary brain. In addition, small cells zhelatinoznoy Substance send processes to the small distance up and down on the surface of the spinal cord, consisting of tract Lissauera, there is serious evidence that the spinal plates brain, there are short intersegmentnye connection notsitseptivnyh cells. Thus, in addition to the three main notsitseptivnyh paths available and polisinaptichnsky ascending path. Notsitseptivnaya information after switch to thalamus, secondary brain reticular formation, and so goes further in the overlying sections of brain. However, in Unlike the special sensory cortex are not available in the specialized area of primary notsitseptsii. Most of the information gets into somestezicheskuyu cortex, but much of it is distributed in the brain diffusely.
pain
