Lu Gwei-Djen and Joseph Needham, “Celestial Lancets: A History and Rationale of Acupuncture and Moxa”, 1980 was topic of an earlier blog post.
Here I present: Lu Gwei-Djen and Joseph Needham, “Celestial Lancets”, 1980. CONTINUED.
INTRODUCTION.
A modern scientific interpretation of acupuncture’ combines neurophysiology, biochemistry’, and connective-tissue mechanotransduction. The traditional “meridian” model overlaps with identifiable neurovascular and fascial pathways.
1. Microanatomy of Acupuncture’ Points.
Acupuncture’ points correspond to:
Dense free nerve endings (Aδ and C fibers).
Muscle spindles and Golgi tendon organs.
Fascial planes with high mechanotransductive potential.
Neurovascular bundles.
Dermis rich in mast cells and CGRP-positive sensory fibers.
Connective-tissue junctions where signaling spreads efficiently.
These structures allow mechanical needle input to trigger biochemical cascades.
2. Local Biochemical Responses.
2.1 Mechanotransduction (Fibroblast + ECM signaling).
Needle rotation or lifting-thrusting causes:
Fibroblast deformation → reorganization of cytoskeleton (actin-integrin pathways).
ECM shear → ATP release.
ATP → ADP → AMP → adenosine, a potent A1-receptor analgesic.
Local reduction of nociceptor firing.
2.2 Dermal Neuroimmune Activation.
Mechanical stimulation produces:
Substance P release.
CGRP release → vasodilation, increased perfusion.
Histamine + tryptase from mast cells.
Nitric oxide (NO) → microcirculation ↑
2.3 Purinergic Analgesia.
Adenosine A1-receptor activation yields:
Local analgesia.
Decreased inflammatory mediator release.
Reduced peripheral sensitization.
This is one of the strongest mechanistic explanations for immediate pain reduction.
3. Peripheral Nervous System Effects.
Afferent Fiber Activation.
Acupuncture’ stimulates:
Aδ fibers → sharp sensory input.
C fibers → dull “deqi” sensation.
Aβ mechanoreceptors → segmental inhibition.
Segmental Spinal Pain Inhibition.
At the dorsal horn:
Enkephalin interneurons activate.
Substance P release declines.
Wide dynamic range (WDR) neuron activity drops.
Gate-control–type suppression reduces regional pain perception.
4. Central Nervous System Effects.
4.1 Endogenous Opioids.
Acupuncture’ triggers:
β-endorphin (pituitary + hypothalamus).
Enkephalins.
Dynorphins.
These circulate systemically and bind opioid receptors to reduce pain.
4.2 Descending Pain Modulation.
Brainstem circuits activated:
PAG (periaqueductal gray).
RVM (rostral ventromedial medulla).
LC (locus coeruleus).
Neurotransmitters involved:
Serotonin (5-HT).
Norepinephrine (NE).
GABA.
Outcome:
Suppression of nociceptive transmission.
Improved pain threshold.
4.3 Limbic & Emotional Regulation.
Functional imaging shows modulation of:
Amygdala.
Insula.
Hippocampus.
Prefrontal cortex.
Biochemical correlates:
↓ Cortisol.
↑ Oxytocin.
Improved autonomic balance.
5. Autonomic Nervous System Effects.
Parasympathetic Activation.
Acupuncture’ increases:
Vagal efferent tone.
Heart rate variability (HRV).
Digestive motility.
Sympathetic Modulation.
Reduces:
Muscle tension.
Vasoconstriction.
Stress-induced cytokine output.
6. Systemic Biochemical & Endocrine Effects.
6.1 Anti-inflammatory
Acupuncture’ mediates:
↓ IL-1β, IL-6, TNF-α
↑ IL-10
Partly through the cholinergic anti-inflammatory pathway.
6.2 HPA Axis Modulation
Cortisol decreases.
Stress physiology normalizes.
Pituitary β-endorphin increases.
6.3 Cardiovascular Effects.
NO-mediated vasodilation.
Reduced blood pressure (RVLM inhibition).
Improved microcirculation
7. Summary Mechanism Table.
