The spleen can regulate circulating blood volume and influence pulmonary circulation and gas exchange . The pancreas and duodenum cooperate each other and complete the functions of digestion and absorption . If the functions of the pancreas and duodenum are normal , the function of digestion and absorption are vigorous , the secretion of glucagon increases , the content of nutrients in the blood increases , and the respiratory muscles can obtain sufficient energy supply , the respiratory function of the lungs will be strengthened . In pathology , when excitability of the sympathetic nerves which control the spleen , pancreas and duodenum weakens , that is , deficiency of spleen-energy , dilatation of the spleen will result in decreasing of circulating blood volume ; absorptive hypofunction of the duodenum , decreasing of glucagon secretion , and increasing of insulin secretion will result in decreasing of content of nutrients in the blood ; increasing of insulin secretion will promote K⁺ to enter into muscle cell , resulting in weakening of excitability of respiratory muscular cells . Decreasing of bloodflow to the lungs , insufficiency of energy supply to the respiratory muscles and weakening of excitability of the respiratory muscles result in respiratory hypofunction of the lungs , showing the syndrome of deficiency of lung-energy such as short and rapid breathing and low voice speaking . In treatment,the method of stacking earth to generate metal is often used.This method of treatment is used in invigorating and benefiting the spleen and stomach to invigorate the lung . In addition , when activity of the parasympathetic nerves which control the duodenum occupies a dominant position , 5-hydroxytryptamine secreted by the duodenum will increase . 5-hydroxytryptamine can cause contraction of smooth muscle , edema of mucous membrane and hypersecretion of mucus in the bronchi , and hypofunction of the lungs , these showing the syndrome such as asthma and cough . This is substance of the viewpoint that " the spleen is the source producing phlegm and the lung is the container storing phlegm " . For treating asthma and cough due to syndrome of phlegm and retention of fluid , in general , the method of invigorating the spleen and eliminating wetness-evil is used to treat its root , and the method of cleaning up the lung and dissipating sputum is used to treat its branch . That is to say , the treatment is , on one side,weakening excitability of the parasympathetic nerves which control the duodenum , reducing 5-hydroxytryptamine secretion , on the other side , strengthening the function of eliminating 5-hydroxytryptamine in the lungs to make organism return to normal . Thus it can be seen that the functions of the spleen , pancreas and duodenum show the positive feedback regulations to the functions of the lungs.

D.Metal ( Lung ) Generates Water ( Kidney )

Respiratory movement of the lungs relates with secretion of antidiuretic hormone and renin . When inspiratory movement occupies a dominant position , secretion of antidiuretic hormone and renin will increase , reabsorption of the kidneys will strengthen , blood volume will increase , and urinary output will decrease . When expiratory movement occupies a dominant position , the results will be opposite . In addition , respiratory movement of the lungs relates with vegetative nervous activity . When inspiratory movement occupies a dominant position , sympathetic nervous excitability will strengthen , catecholamine secreted by medulla of the adrenal glands will increase . When expiratory movement occupies a dominant position , the results will be opposite . Inside the lungs , angiotensin Ⅰ can be degraded into angiotensin Ⅱ which has higher activity . Angiotensin Ⅱ can promote secretion of aldosterone in cortex of the adrenal glands and strengthen reabsorption of the kidneys . The lungs can synthesize prostaglandins , and PGA in them can cause increasing of bloodflow of the kidneys , sodium and potassium output in urine and urinary output . In pathology , respiratory exhaustion can lead to renal dysfunction , even acute renal insufficiency , the latter showing the dysfunctions such as oliguria , azotemia and metabolic acidosis . Thus it can be seen that the functions of the lungs show the positive feedback regulation to the functions of the adrenal glands and the kidneys.

E.Water( Kidney ) Generates Wood( Liver )

Catecholamine secreted by medulla of the adrenal glands can lead to contraction of hepatic sinusoid and promote decomposition of sugar , fat and protein in the liver . Aldosterone secreted by cortex of the adrenal glands promotes reabsorption of the kidneys to sodium and water , so that blood volume increases , and bloodflow of the liver increases as well . Glucocorticoid secreted by cortex of the adrenal glands promotes intrahepatic glyconeogenesis , inhibits decomposition and uses of glucose , and increases blood-sugar level . The kidneys are urinary organs . They can regulate blood volume , so they can influence bloodflow of the liver . Erythropoietic factor secreted by juxta-glomerular cell acts on erythropoietinogen produced by the liver and transform it into active erythropoietin which can accelerate erythrogenesis . Androgen secreted by the adrenal glands and testicles promotes synthesis of protein in the liver and causes positive nitrogen balance .

Androgen , estrogen and progestin secreted by cortex of the adrenal glands and sex glands all are inactivated in the liver . In pathology , when deficiency of kidney-yin and increasing of catecholamine and glucocorticoid secreted by the adrenal glands occur , hepatic sinusoid will contract , the function of inactivation in the liver will strengthen , the syndrome of hyperactivity of fire due to deficiency of liver-yin will appear . In treatment , the method of nourishing water to maintain wood is often used . This method of treatment is used in nourishing kidney-yin to inhibit liver-fire . When deficiency of kidney-yang occurs , and the functions of the adrenal glands and sex glands weaken , the functions of the liver will weaken as well . Thus it can be seen that the functions of the adrenal glands , kidney and sex glands show the positive feedback regulation to the functions of the liver.

(3).Substance of Restriction among Five Elements System for Human Body

The restriction among five elements system for human body reflects the negative feedback regulation among the organs assemblages which constitute the five zang-organs . In the following , we will demonstrate the negative feedback regulation among the five zang-organs from artery supply and other physiological functions.

A.In Artery Supply

The trunk of the arteries of the general circulation is the aorta,and the arteries supplying various organs all are the branches of the aorta . Arterial blood pressure of the artery supplying each organ is inversely proportional to the distance of this artery from the heart , that is , the longer the distance of this artery from the heart is , the lower the arterial blood pressure is . The left and right coronary arteries which supply the heart , and the innominate artery and the left and right common carotid arteries which supply the brain , thyroid gland and parathyroid glands branch from the aorta first , then , the bronchial branches which supply the lungs branch from the aorta . Therefore , blood supply of the heart , brain , thyroid gland and parathyroid glands is more dominant than that of the lungs . This is substance of the relation that fire ( heart ) restricts metal ( lung ) .

After that , the coeliac trunk branches from the aorta . The common hepatic artery and its continuation ---- the proper hepatic artery and the left and right hepatic branches which supply the liver branch from the coeliac trunk earlier than the splenic artery and its branches which supply the spleen , pancreas and duodenum . Therefore , blood supply of the lungs is more dominant than that of the liver , and blood supply of the liver is more dominant than that of the spleen , pancreas and duodenum . This is substance of the relations that metal ( lung ) restricts wood ( liver ) , and wood ( liver ) restricts earth ( spleen ).

Next , the suprarenal arteries which supply the adrenal glands , the renal arteries which supply the kidneys , and the testicular arteries ( in the male ) or the ovarian arteries (in the female) which supply sex glands branch from the aorta in proper order . Therefore , blood supply of the spleen , pancreas and duodenum is more dominant than that of the adrenal glands , kidneys and sex glands . This is substance of the relation that earth ( spleen ) restricts water ( kidney ).

The arteries which supply the heart , brain , thyroid gland and parathyroid glands branch from the aorta the earliest , which the arteries which supply the adrenal glands , kidneys and sex glands branch from the aorta the latest . However , because the position of the adrenal glands , kidneys and sex glands is the lowest , blood supply of these organs takes advantage of gravity . In addition , when bloodflow of these organs increases relatively , bloodflow of the heart , brain , thyroid gland and parathyroid glands must decrease relatively . This is substance of the relation that water ( kidney ) restricts fire ( heart ) ( Fig.3-2 ) .

In short , one of the evidences about the restriction among the five zang-organs is the fact that the arteries which supply the organs assemblages which constitute substance of the five zang-organs branch from the aorta in turn . Therefore , when bloodflow of the heart , bain , thyroid gland and parathyroid glands increases relatively , bloodflow of the lungs will decrease relatively , that is , fire restricts metal ; when bloodflow of the liver increases relatively , bloodflow of the spleen , pancreas and duodenum will decrease relatively , that is , wood restricts earth ; when bloodflow of the spleen , pancreas and duodenum increases relatively , bloodflow of the adrenal glands , kidneys and sex glands will decrease relatively , that is , earth restricts water ; when bloodflow of the adrenal glands , kidneys and sex glands increases relatively , bloodflow of the heart , brain , thyroid gland and parathyroid glands will decrease relatively , that is , water restricts fire . Generally speaking , when bloodflow of an organ increases , its functions will strengthen ; when bloodflow of an organ decreases , its functions will weaken . Therefore , the organs assemblages which constitute the five zang-organs realize the negative feedback regulations by relative positions of the arterial branches .

B.In Other Physiological Functions

Besides realizing the negative feedback regulations by relative positions of the arterial branches , the five zang-organs realize the negative feedback regulations by other ways .

Fire Restricts Metal: The yang-natured hormones act on the heart to strengthen the function of the heart . This effect can resist the effect of decreasing blood pressure caused by prostaglandin , bradykinin and endophine which are secreted by the lungs . In addition , the effect of weakening the function of the heart caused by parathyrin and atriopeptins can resist the effects of increasing blood pressure and promoting metabolism caused by angiotensin , vasoactive intestine polypeptide and cortisone which are secreted by the lungs . Thus it can be seen that the functions of the heart , thyroid gland and parathyroid glands show the negative feedback regulations to the functions of the lungs .

Metal Restricts Wood: The effects of decreasing blood pressure and weakening respiration caused by prostaglandin , bradykinin and endophine which are secreted by the lungs can resist the effects of promoting metabolism of the liver , contracting hepatic sinusoid and increasing blood pressure caused by yang-natured hormones . In addition , the effects of increasing blood pressure and promoting catabolism in the liver caused by angiotensin , vasoactive intestine polypeptide , cortisone and others which are secreted by the lungs can resist the effect of promoting anabolism in the liver caused by insulin and growth hormone . Thus it can be seen that the functions of the lungs show the negative feedback regulations to the functions of the liver.

Wood Restricts Earth: When hepatic sinusoid contracts , regurgitation resistance of the splenic vein will increase , and blood storage of the spleen will increase ; when hepatic sinusoid dilates , blood storage of the liver will increase , but blood storage of the spleen will decrease relatively . In addition , strengthening of decomposition of hepatoglycogen and increasing of blood sugar level can inhibit secretion of insulin . Thus it can be seen that the functions of the liver show the negative feedback regulation to the functions of the spleen and pancreas.

Earth Restricts Water: Contracting of the spleen , decreasing of blood storage in the spleen , strengthening of absorption of water in the duodenum can result in increasing of circulating blood volume to resist the effect of decreasing blood volume caused by filtration of the kidneys . The effect of decreasing blood sugar caused by insulin which is secreted by the pancreas can resist the effect of increasing blood sugar caused by catecholamine and glucocorticoid which are secreted by the adrenal glands . In addition , the effect of dehematization of the spleen can resist the effect of promot- ing erythrogenesis caused by erythropoietic factor which is secreted by juxtaglomerular cell. Thus it can be seen that the functions of the spleen and duodenum show the negative feedback regulations to the functions of the kidneys.

Water Restricts Fire: Increasing of reabsorption of water in the kidneys and increasing of blood volume can inhibit the compensation of quickening of heart beat and strengthening of heart contractility caused by decreasing of blood volume . The effect of strengthening the function of the heart caused by catecholamine which is secreted by medulla of the adrenal glands can resist the effect of weakening the function of the heart caused by increasing of cardionatrin which is secreted by the heart , increasing of excitability of cardiac branches of the vagus nerve , and increasing of parathyrin which is secreted by the parathyroid glands . In addition , the effects of promoting diuresis and decreasing blood volume caused by acting of prostaglandin on the kidneys can resist the effect of increasing blood pressure caused by strengthening the function of the heart . Thus it can be seen that the functions of the adrenal glands and kidneys show the negative feedback regulations to the function of the heart.

(4).Substance of Subjugation and Reverse Restriction among Five Elements System for Human Body

The relations of subjugation and reverse restriction among five elements system for human body reflect the feedback regulations among the organs assemblages which constitute the five zang-organs in pathological state . The feedback regulations of subjugation and reverse restriction among five elements system for human body are realized by the relative positions of arterial branches of the organs assemblages which constitute the five zang-organs.

When bloodflow of the heart , brain , thyroid gland and parathyroid glands increases , that is , overabundance of fire occurs , bloodflow of the adrenal glands , kidneys and sex glands will decrease relatively , that is , fire restricts water reversely ; bloodflow of the lungs will decrease relatively as well , that is , fire subjugates metal . When bloodflow of the heart , brain , thyroid gland and parathyroid glands decreases , that is , insufficiency of fire occurs , bloodflow of the adrenal glands , kidneys and sex glands will increase relatively , that is , water subjugates fire ; bloodflow of the lungs will increase relatively as well , that is , metal restricts fire reversely . Others are on the analogy of this . When pathological changes occur in a certain zang-organ , bloodflow of the organs assemblage which constitute this zang-organ will change . This results in changing of bloodflow of the organs assemblages which constistute the other zang-organs . This is substance of feedback regulations of subjugation and reverse restriction among the five zang-organs in pathological condition.

[3].Substance of Matching of Five Elements System for Nature with That for Human Body

Matching of five elements system for nature with that for human body constitutes the macrosystem of five elements which reflects the viewpoint that human , as a microcosm , is connected with the macrocosm . From this macrosystem of five elements , we can see such prospect :

When the earth revolves around the sun for one cycle , it undergoes spring , summer , late summer , autumn and winter four seasons . The weather in the earth undergoes the replacement of wind , summer-heat , wetness , dryness , and cold . Because of the change of weather , in spring , human body easily shows syndrome such as hypertension and conjunctivitis caused by liver-wind stirring inside ; in summer , human body easily shows syndrome of hyperactivity of fire caused by deficiency of heart-yin , such as dry mouth , red tongue and insomnia , because uncontrolled hyperactivity of heart-fire produces increasing of thyroxinic secretion and strengthening of cardiac function ; in late summer , human body easily shows syndromes of the spleen or dysfunction of digestion caused by hot and suffocating weather , higher humidity , and fast multiplication of bacteria ; in autumn , human body easily shows syndromes of the lung , such as asthma and cough , because of increasing of secretion of 5-hydroxytryptamine in the respiratory tract which is caused by dryness of weather and increasing of positive ions ; in winter , the weather is cold , urinary output of the kidneys increases , secretion of sex hormones by sex glands decreases , therefore , human body easily shows syndrome of kidney asthenia , such as polyuria and hyposexuality.

In the society life , human can show emotional changes , such as anger , overjoy , overthink , sorrow and fear . Anger can influence the functions of the liver ; overjoy can influence the functions of the heart , brain , thyroid gland , and parathyroid glands ; overthinking can influence the functions of the spleen , pancreas and duodenum ; sorrow can influence the functions of the adrenal glands , kidneys and sex glands.

Pathological changes of the liver can influence the gallbladder , tendons and eyes . In this state , the skin shows green color , because the blood in the veins flows slowly . Pathological changes of the heart , brain , thyroid gland and parathyroid glands can influence the small intestine , blood vessels and tongue . In this state , the skin shows red color , because the blood in the arteries flows quickly . Pathological changes of the spleen , pancreas and duodenum can influence the stomach , muscles , and oral cavity . In this state , the skin shows yellow color because dysfunction of digestion and absorption , and anemia occur.Pathological changes of the lungs can influence the large intestine , skin and hair , and nose . In this state , the skin shows white color , because deficiency of capillary perfusion occurs . Pathological changes of the adrenal glands , kidneys and sex glands can influence the urinary bladder , bones and ears . In this state , the skin around the orbits shows black color , because venular dilatation occurs .

In treatment , pathological changes of the liver are treated by the sour drugs , pathological changes of the heart , brain , thyroid gland and parathyroid glands are treated by the bitter drugs ; pathological changes of the spleen , pancreas and duodenum are treated by the sweet drugs ; pathological changes of the lungs are treated by the acrid drugs ; pathological changes of the adrenal glands , kidneys and sex glands are treated by the salty drugs.

This is the thought of macrosystem explicated by the theory of five elements in Sinomedicine . The macrosystem in which " human , as a microcosm , is connected with the macrocosm " is embodiment of harmony and order of the cosmical movement .

4.Summary