It encloses and protects the xin-heart and the diseases of the pericardium result in dysfunction of the xin-heart.

The Functions of the Fu Organs
In general the traditional functions of the fu organs are very similar to their functions in Western medicine. Each fu organ channel connects internally and externally with a zang organ channel. This can have therapeutic importance in that a point on the fu channel may be used to treat a problem on its connected zang channel, and vice versa.

The small intestine
The small intestine connects with the xin-heart. The small intestine receives and digests food from the stomach. It absorbs the pure part and distributes it to the whole body, the impure part going on to the large intestine. This function of the small intestine belongs to the transforming and transporting function of the pi-spleen.

The gall-bladder
The gall-bladder connects with the gan-liver. It stores and discharges bile. The expulsion of bile from the gall-bladder is closely related to the freeing function of the gan-liver. The gan-liver and the gall-bladder take charge of freeing together, and jaundice results when this function is deranged.

The stomach
The stomach connects with the pi-spleen. The stomach stores and digests food, passing it on to the small intestine. A deficiency of qi of the stomach causes indigestion, epigastric pain and sour regurgitation When the qi of the stomach ascends then nausea, heartburn, vomiting, hiccoughs and flatulence occur.

The large intestine
The large intestine connects with the fei-lung. The large intestine absorbs the residue of water and turns the rest of the food into feces. Disturbance of this function results in diarrhea or constipation due to the 'descent of qi'.

The urinary bladder
The urinary bladder connects with the shen-kidney. The bladder stores and then discharges urine from the body.

The sanjiao
In Chinese the sanjiao means the three cavities. The xin-heart and the fei-lung are in the upper jiao (the chest), and they transport qi and blood to all parts of the body in order to nourish the body. The pi-spleen and stomach are in the middle jiao (the epiastrium) and they digest and absorb food. The shen-kidney and bladder are in the lower jiao (the hypogastrium) and they control water metabolism and the storage and excretion of water. The sanjiao is also sometimes called the triple warmer organ. This is because the three body cavities are intended to control the body temperature.

Extra Organs

The brain
The brain is a sea of marrow, i.e. it is an enlarged part of the spinal cord. The shen-kidney produces the marrow that fills the brain. If the essence of shen-kidney is absent then there is inadequate marrow for the brain. In traditional Chinese medicine the function of the mind is included in that of the xin-heart.

The uterus
The function of the uterus is to control the menstrual cycle, develop the embryo and nourish the foetus. The qi and blood of the channels pass into the uterus through the chong and the ren channels, so that the qi of the body is able to influence the flow and regularity of the menstrual cycle.