What is the role of substantia gelatinosa?
What is the role of substantia gelatinosa?
Substantia gelatinosa is a collection of cells in the gray area (dorsal horns) of the spinal cord. Found at all levels of the cord, it receives direct input from the dorsal (sensory) nerve roots, especially those fibers from pain and thermoreceptors.
What are Rexed laminae?
Definition. Rexed’s laminae is an architectural classification of the structure of the spinal cord, based on the cytological features of the neurons in different regions of the gray substance described by the Swedish Anatomist B. Rexed.
What is Lissauer’s tract?
Lissauer’s tract is a pathway formed from the proximal end of small unmyelinated and poorly myelinated fibers in peripheral nerves, which enter at the lateral aspect of the dorsal horn and ascend and descend up to four segments, and terminate in Rexed’s laminae I through to VI (principally I, II, and V) of the …
What lamina is substantia Gelatinosa?
Lamina 2. Lamina 2, also called “substantia gelatinosa”—a term first introduced by Rolando (1824) for its translucent appearance due to its lack of myelinated fibers—consists of projection neurons (Golgi type I neurons) and local interneurons (Golgi type II neurons).
Which lamina is substantia Gelatinosa?
Lamina 2
Lamina 2. Lamina 2, also called “substantia gelatinosa”—a term first introduced by Rolando (1824) for its translucent appearance due to its lack of myelinated fibers—consists of projection neurons (Golgi type I neurons) and local interneurons (Golgi type II neurons).
What is the function of the laminae?
The gray matter of the spinal cord is composed of nine distinct cellular layers, or laminae, traditionally indicated by Roman numerals. Laminae I to V, forming the dorsal horns, receive sensory input. Lamina VII forms the intermediate zone at the base of all horns.…
What tract carries Kinesthesia?
The posterior column–medial lemniscus pathway is responsible for transmitting pressure and position senses; the spinothalamic tract mediates the sensation of pain and temperature.
What happens if grey matter is damaged?
Since the neuronal cells of the grey matter are constantly working, they require a high supply of oxygen to function efficiently. Therefore when the grey matter does not have access to oxygen, the cells will begin to die, leading to possible irreversible brain damage and loss of function.
What does grey matter do in spine?
The grey matter includes regions of the brain involved in muscle control, and sensory perception such as seeing and hearing, memory, emotions, speech, decision making, and self-control. The grey matter in the spinal cord is split into three grey columns: The anterior grey column contains motor neurons.
How are substantia gelatinosa neurons activated?
A significant proportion of the substantia gelatinosa neurons receive direct input from C fibers and indirect input from A-delta fibers from lamina I and deep dorsal horn. These neurons are frequently excited by activation of thermal receptive or mechanical nociceptive afferents.
What is the substantia gelatinosa of Rolando?
Substantia gelatinosa of Rolando is Rexed lamina II, labeled at upper left. The apex of the posterior grey column, one of the three grey columns of the spinal cord, is capped by a V-shaped or crescentic mass of translucent, gelatinous neuroglia, termed the substantia gelatinosa of Rolando (or SGR)
Where can I find substantia gelatinosa centralis?
For the substantia gelatinosa centralis, see Central gelatinous substance of spinal cord. Substantia gelatinosa of Rolando is Rexed lamina II, labeled at upper left.
What is substantia gelatinosa of the spinal cord?
The substantia gelatinosa of the spinal cord was given its name by Rolando in 1824 (quoted by Ramón y Cajal, 1909 ), based on the translucent and gelatinous appearance it possesses when examined in fresh tissue ( Fig. 1 ).
