II. The Marrow
The marrow is a kind of grease material ,which is stored in the bone cavities. As the locations of marrow are different, they each have their own names, the bone marrow, the spinal marrow and the brain. The spinal marrow communicates with the brain, flowing up to the brain and clown to the coccyx,which is thus called the cerebrospinal cord.
The formation of marrow is related to the congenital essence and acquired essence.Fundamentally, the marrow is manufactured by the kidney-essence. The kidney stores the essence which manufactures the marrow. Furthermore, the essential substances produced from food and drink supplies nourishment to the bone marrow via the bone cavity, which reinforces the brain. Thus, either insufficiency of congenital essence, or impairment of the acquired essence may affect marrow formation.
In summary, the physiological function of the marrow is manifested in three aspects.They are to nourish the brain,supplement the bones and engender the blood. The function of nourishing the brain and supplementing the bones have been discussed in the part on the function of the kidney. Exposition concerning the marrow engendering the blood is seldom seen in the classic works,however,the ancients still had a preliminary understanding. In clinical practice,certain disorders of the blood system,such as aplastic anemia,is often treated by reinforcing the kidney-yin and supplementing kidney-essence.This also provides a theoretical basis for the theory of the essence engendering the blood.
