Acupuncture Mechanisms for Meaningful Long-Term Effects

Abstract

In our clinical research we have drawn the conclusion that meaningful long-term (> 6 months) pain relieving effects can be seen in a proportion of patients suffering from nociceptive pain. What are the mechanisms behind this?

From the existing experimental data some important conclusions can be drawn:

• Much of the animal research only represents short-term hypoalgesia probably induced by the mechanisms behind stress-induced analgesia (SIA) and the activation of diffuse noxious inhibitory control (DNIC).

• Almost all experimental acupuncture research has been performed with electro-acupuncture (EA) even though therapeutic acupuncture is mostly gentle manual acupuncture (MA).

• Most of the experimental human acupuncture pain threshold (PT) research shows only fast and very short-term hypoalgesia, and, very important, PT elevation in humans does not predict the clinical outcome.

• The effects of acupuncture may be divided into two main components - acupuncture analgesia and therapeutic acupuncture.

A hypothesis on the mechanisms of therapeutic acupuncture will include:

Peripheral events that might improve tissue healing and give rise to local pain relief through axon reflexes, the release of neuropeptides with trophic effects, dichotomising nerve fibres and local endorphins.

Spinal mechanisms that involve such as the gate-control, long-term depression, propriospinal inhibition and the balance between LTD and LTP.

Supraspinal mechanisms through the descending pain inhibitory system, DNIC, the sympathetic nervous system and the HPA-axis. Perhaps is oxytocin involved in the long-term effects.

Cortical, psychological, “placebo” mechanisms from counselling, reassurance and anxiety reduction.

Zusammenfassung

Die Ergebnisse unserer klinischen Forschung ließen die Schlussfolgerung zu, dass mittels Akupunktur bei einem Teil der Patienten, die unter nociceptiven Schmerzen litten, bedeutsame Langzeit-Effekte (> 6 Monate) zu erzielen sind. Was sind die hierfür verantwortlichen Funktionsweisen?

Auf Grundlage der existierenden Forschungsdaten können einige Schlussfolgerungen gezogen werden:

• Ein großer Teil der an Tieren durchgeführten Forschungen zeigt nichts anderes als Kurzzeit-Hypalgesie. Die hierfür verantwortlichen Mechanismen sind möglicherweise Stress-induzierte-Analgesie (SIA) und die Aktivierung der diffuse noxious inhibitory control (DNIC).

• Fast alle experimentellen Forschungen zur Akupunktur wurden mit Elektroakupunktur (EA) durchgeführt, dies, obwohl Akupunktur in der klinischen Praxis als zarte manuelle Stimulationsakupunktur (MA) Anwendung findet.

• Die meisten Forschungen zur menschlichen Schmerzschwelle (PT) zeigen nur schnelle und Kurzzeit-Hypalgesien. Weiterhin: Die Anhebung der menschlichen Schmerzschwelle steht in keinerlei Beziehung zum klinischen Ergebnis.

• Die Effekte der Akupunktur können demnach in zwei Hauptaspekte unterteilt werden - Akupunkturanalgesie und therapeutische Akupunktur.

Eine Hypothese zu den Wirkungsweisen der therapeutischen Akupunktur muss folgende Aspekte in Betracht ziehen:

Periphere Geschehnisse, die einen Einfluss auf die Gewebsheilung haben und die die lokale Schmerzverarbeitung durch Axonreflexe beeinflussen, die Ausschüttung von Neuropeptiden mit trophischen Effekten, aktivierende und hemmende Nervenbahnen und lokale Endorphine.

Spinale Mechanismen wie die der Gate-Control, Langzeithemmung, propriospinale Hemmung und die Balance zwischen LTD und LTP.

Supraspinale Mechanismen durch absteigende Schmerzhemmungs-Bahnen, das DNIC, das sympatische Nervensystem und die HPA-Achse. Möglicherweise ist auch Oxytocin an Langzeiteffekten beteiligt.

Kortikale, psychologische „Placebo”-Effekte durch Zuwendung, Beruhigung und Abbau von Ängstlichkeit.

Keywords

Acupuncture - mechanisms - therapeutic acupuncture - acupuncture analgesia - axon reflexes - long term depression - oxytocin

Schlüsselwörter

Akupunktur - Funktionsweisen - therapeutische Akupunktur - Akupunkturanalgesie - Axonreflexe - Langzeithemmung - Oxytocin

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