The Relationship of the Lung to other Organs
1) Correlating with the Skin and Hair
"Correlating with" here means " association. " The skin and hair include the surface skin, sweat gland, body hair, etc. For example' the exterior of the human body is a protective screen fighting off attacks of external evil. Traditional Chinese medicine holds that the skin and hair have functions in excreting sweat, defending the human body, preventing invasion from exogenous evil, etc. All these must depend on the physiological activity of the lung: Thus, Chapter 38 in the Plain Questions states: "The surface skin and body hair correlate with the lung. " Chapter 10 also states that: " the lung corresponds with the surface skin, and its flourish manifests in the body hair. "
The correlating relationship between the lung and the skin and hair are manifested in the following two aspects: The first one is that the lung dominates qi, and pertains to Defence, which has the function of dispersing defense-qi, and scattering the essential substances to the body's surface, here nourishing and warming the skin and hair. The second one is that the skin and hair assist the lung in regulating the respiratory function. The opening and closing of the pores possess the function of scattering lung-qi and regulating respiration. The sweat pore is known in the Internal Classic as the "portal of gas", in which the gas can exit and enter.
As a result of this inter-coordinating relation, the lung and skin often affect each other in pathology. For example, when a person is attacked by the exogenous evil-qi, the skin and hair are usually the first to be invaded. Further impairment of the physiological function of the lung will result in an aversion to cold, fever, nasal obstruction, and cough. If lung-qi is deficient, there will be failure to disperse, distribute defense-qi, essence and body fluids will be impeded, wanness and shallow skin may occur, and withered hair will appear. If the function of defense-qi is diminished, there will be frequent spontaneous perspiration, hence susceptibility to the common cold. If lung-qi is obstructed, the sweat pores are closed, resulting in unhidrosis, asthma, etc.
2) Opening into the Nose
The nose is the portal of the lung, and is the part of the pathway through which the gas exits and enters. Its physiological functions consist of ventilation and smelling. These depend on the smooth flow of lung-qi. When lung-qi is in harmony, the nose will be unobstructed, the respiration smooth, and the sense of smell active. Thus Chapter 17 in the Spirit Pivot states: "A normal nose is able to differentiate a sweet smell from a foul smell because lung-qi permeates the nose. "
Because of the nose being the opening of the lung, the two organs, often influence each other when either is diseased. For example, if the lung is attacked by the evil-qi, it fails to perform its dispersing function, and leads to dysfunction of the nose. This results in nasal obstruction, runny nose, anosmia and nosebleed, etc. The person is injured by the fact that most of the exogenous evil-qi invade the human body via the mouth and nose. The lung is then invaded by the warm-heat evil-qi, giving rise to fever, thirst,c0ugh, yellow sputum and vibration of the ala nasi, etc. Nose disorders are often cured by starting with the lung.
3) Throat as a Gateway of the Lung
The throat is a gateway through which the air of the respiratory tract is inhaled and exhaled. It contains the vocal organs, through which the Lung Meridian passes, so its ventilation and phonation are directly related to the lung. If lung-qi is in harmony, the ventilating function of the throat will be normal, producing a sonorous voice, If lung-qi is deficient, there will be a low voice, hoarseness of voice, even aphonia. This is known as "broken metal could not sound. " If lung-qi is retarded, there will be a loud voice, coarse breathing, even hoarseness, or aphonia. This is known as "solid metal could not sound. "The disorders of the throat also usually affect the respiratory function of the lung, resulting in stuffed sensations in the chest, asthma, even asphyxia.
