From some recent research work it would seem that not all types of acupuncture are blocked by anti-morphines. If a patient has a painful arthritic knee, and acupuncture provides relief for the knee pain, then anti-morphines do not usually block the effects of this type of acupuncture therapy. The effects of acupuncture can be very swift (in terms of seconds) and it seems that the release of chemicals might possibly be too slow a process to have such a swift action. The endorphin theory again only deals with pain and makes little attempt to explain the use and effects of acupuncture in non-painful diseases.
No Real Answer?
The fact of the matter is that acupuncture does work, and has been shown to do so, but the exact answer as to how it works is unclear. The current scientific explanations give a logical and supportable basis for stating that it does have an effect on the nervous system, but it is difficult to draw any more definite conclusions.
The mechanism of pain perception and transmission has not been clearly and completely defined, and in the light of the current state of knowledge about the basic mechanism of pain it is a little unreasonable to expect an explanation of the effects of acupuncture on pain.
The Autonomic System
It is fascinating to speculate about the mechanism of acupuncture in the non-painful diseases, such as asthma. The autonomic nervous system control's the body's breathing, heart beat and digestion. It continues to function without any conscious will, but it should not be confused with the unconscious mind, frequently alluded to in text-books on psychology. It is really better to think of the autonomic system as the automatic base or foundation on which the body is built. We understand very little about the way in which the autonomic system works, and even less about how acupuncture might affect this system.
Asthma is due to a contraction of the small breathing tubes that allow air to enter the lungs. As these tubes contract, and become gummed up, the air flow in the tubes becomes turbulent, causing the whistle or wheeze that is heard in asthma. The small breathing tubes are lined with muscle, and this muscle is largely controlled by the autonomic system. When acupuncture is used to treat this type of disease it is logical to suppose that it works through the autonomic system, and it seems possible that many of the effects of acupuncture, on diseases like indigestion and diarrhoea, work through the same system, but as yet there are no unified theories that explain either the autonomic system or the effects of acupuncture on this system.
It is quite likely that when we understand this system a little more fully we will be able to understand the mechanism of acupuncture a little better. It is also possible that the body is influenced far more by the autonomic system than we now believe. If the autonomic system is anaesthetized, then severe intractable pain can sometimes be alleviated; for instance, if severe arm pain is experienced then it may be possible to cure the arm pain by infiltrating local anesthetic into the autonomic nerves that supply the arm. As the local anaesthetic wears off so the arm pain returns. This observation has no real explanation at the moment, because the interplay between pain and the autonomic system is unexplained.