Pain ascending

O Pain is an unpleasant subjective experience that is the net effect of a complex interaction of the ascending and descending nervous systems involving biochemical, physiologic, psychological, and neocortical processes. 

Stimulation of a nociceptor in the periphery of the body elicits action potentials in the first-order neuron, which transmits the signal to the second-order neuron in the dorsal horn of the spinal cord. From the spinal cord, the signal is transmitted to several regions of the brain. The most prominent ascending nociceptive pathway is the spinothalamic tract. Axons of the second-order sensory neurons project to the contralateral (opposite) side of the spinal cord and ascend in the white matter, terminating in the thalamus (see Figure 8.1). The thalamus contributes to the basic sensation or awareness of pain only it cannot determine the source of the painful stimulus. 

Figure 8.2 The endogenous analgesic system. The three major components of the endogenous analgesic system include the periaqueductal gray matter in the midbrain nucleus raphe magnus in the medulla and pain inhibitory complex in the dorsal horns of the spinal cord. This system causes presynaptic inhibition of pain fibers entering the spinal cord. The binding of enkephalin to opioid receptors on the pain fibers prevents release of the neurotransmitter, substance P. As a result, the pain signal is terminated in the spinal cord and does not ascend to higher centers in the CNS.

Mechanism of Action-. An opioid agonist that binds to opioid receptors at many sites in the CNS, particularly in the medulla. This action inhibits the ascending pain pathways. Therapeutic Effect Alters the perception of and emotional response to pain, suppresses cough reflex. 

Acute intoxication after overdoses is characterized by burning throat pain, bloody diarrhea, shock, hematuria, and oliguria. Fatal ascending... 

Bai Zhi is warm and pungent with a rich aromatic smell it possesses strong ascending properties. As it can expel wind-cold, transform phlegm and pus and dry dampness, it can therefore reduce swelling and open the obstruction of the nose. Because it enters not only the Lung meridian, but also the Stomach meridian, it is often applied to treat pain in the... 

Wu Zhu Yu is very pungent, bitter and hot, and enters the Liver, Spleen and Kidney meridians. It can warm the meridian, descend the Liver-Qi and treat ascending of the Liver-Qi due to excess cold in the Liver meridian. The indication is headache, particularly on the top of the head. In addition, Wu Zhu Yu can spread the Liver-Qi and can be used when the Liver-Qi attacks the Stomach, which manifests as cramping pain with a cold sensation in the Stomach and in the lateral sides of the lower abdomen, vomiting of clear fluid, and a wiry and slow pulse. This pattern can be found in disorders such as migraine, hypertension, peptic ulcer, chronic gastritis and dysmenorrhea. 

Herbs that promote blood circulation and break up congealed blood can injure the Stomach and Spleen, disturb their ascending and descending functions and cause nausea, fullness or pain of the stomach. Zhi Gan Cao, Sheng Jiang and Da Zao are often used to prevent these disorders. 

These six herbs are effective for treating Bi syndrome as a result of cold. They are very hot and pungent, and have strong ascending and dispersing abilities. They can strongly disperse wind, cold and dampness, intensively warm the meridians, accelerate the movement of Qi and blood, and thus effectively relieve pain. 

They are often selected as assistants in formulas to treat disharmony between the Liver and Spleen. Fang Feng enters the Liver and Spleen meridians, can effectively disperse Qi stagnation and relieve cramp and distension when the Liver attacks the Spleen. Since it ascends and spreads the Spleen-Qi, it can treat borborygmi and diarrhea. Chen Pi can promote Qi movement in the Stomach, reduce the sensation of fullness in the Stomach and improve appetite. Zhi Shi can descend the Qi in the intestines and reduce pain and distension in the abdomen. 

Zhi Shi serves as assistant. It descends the Qi in the intestines and reduces the distension and pain. When the ascending Chai Hu and the descending Zhi Shi are used together, they can properly regulate the Liver-Qi and the Qi in the intestines. 

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