Pueraria: a beta-blocker?

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Introducing Pueraria:
Pueraria aka 葛根 (gegen) is known in Chinese Medicine to have the following broad functions:
1. 解肌退热: e.g. for fever and chills with an added symptom of a a stiff nape
2. 透疹: usually to bring the ‘poison’ in skin diseases to the surface
3. 生津止渴: for treating 消渴证, a close cousin of what is labelled as diabetes these days
4. 升阳止泻 : for certain kinds of diarrhea (the damp-heat type)
With the above in mind, here are some of the biochemical and pharmaceutical properties of Pueraria that I discovered recently:
1. main component is flavanoids (黄酮类物质)
2. has a string of functions that are cardiovascular in nature (yes, all written in mandarin):
o 葛根素均能对抗垂体后叶素引起的急性心肌缺血
o 葛根素能改善微循环，提高举步维血流量，抑制血小板凝集
o 葛根总黄酮能扩张冠脉血管和脑血管，增加冠脉血流量和脑血流量，降低心肌耗氧量，增加氧供应
o 葛根能直接扩张血管，使外周阻力(peripheral resistance)下降，而有明显降压作用，能较好缓解高血压病人的“项强”症状
o 葛根有广泛的beta-受体阻滞作用
Beta-blockers:
The last function says that it is a beta-receptor antagonist. This means it blocks beta-receptors from receiving signals it normally can receive, and because these signals usually serve a purpose that purpose can no longer be manifest. Two well known beta-receptors are beta-1 and beta-2. There is also beta-3. Each type of receptor is known to congregate more in certain places.
• beta-1 receptors congregate in huge quantity on the membrane of cardiac muscle cells. When signals come in the form of norepinephrine from the nerve endings of the sympathetic nervous system, the heart beats faster and pumps harder. Beta-1 blockers will prevent this from happening, and is useful if you have at hand an overactive heart.
• beta-1 receptors also congregate near the glomerulus of the kidneys, passing on the signal to produce more renin, which activates the RAAS system. Blocking these receptors will cause a fall in renin production causing a string of events that reduce blood pressure and reduce urine production.
• beta-2 receptors congregate on bronchial smooth muscle (支气管平滑肌)，coronary artery (冠状动脉) and skeletal muscle blood vessels (骨骼肌血管). Without blockers at hand, signals will cause dilation in these areas. However, beta-2 blockers may pose a risk to those with a history of asthma. For these people, their bronchial smooth muscles may constrict easily, causing another asthma attack.
• beta-3 receptors hang out in fat cells. To my knowledge, there is to date no known pharmaceutical drug that can facilitate or block these receptors.
Beta-blockers may slow down the breakdown of lipids. it can also help diabetics using insulin to lengthen the time taken for blood glucose levels to rise again after the insulin has brought the levels down.
Propranolol the beta-blocker:
Propranolol (普萘洛尔 aka 心得安) is a well-known beta-blocker used for arrhythmia, angina pectoris, high blood pressure, as well as hyperthyroidism. Its action on beat-receptors is non-selective i.e. it blocks both beta-1 and beta-2 receptors. Hence, hypertensive folks also suffering from asthma should not use it lest the beta-2 receptors of their bronchial smooth muscles are blocked as well, making acute and existing situation.
Pueraria’s action on the cardiovasculature:
Can Pueraria’s properties as described by Chinese Medicine be explained by its tonifying action on the cardiovasculature? My speculative thoughts on this:
1. for fever and chills with an added symptom of a a stiff nape, a better flowing cardiovasculature may facilitate both perspiration and the work of our immune system
2. for skin diseases, promoting blood flow can increase metabolism and hasten the process of detoxification
3. for treating 消渴证 which has traditionally been described as a case of 气阴两虚, we could think of pueraria as an inhibitor of renin production that reduces the amount of urine passed out. this treats a symptom of 消渴 which is 尿多. and because 气随津脱, reducing fluid loss also conserves qi.
4. For treating damp-heat type diarrhea, the idea of hastening the process of detoxification can once again be used.

From needleplant.com