Photobiomodulation Therapy (PBMt)—Clinical Application of Pain Management for Animals

Photobiomodulation therapy (PBMt) has been developed since the first generation of lasers in 1960 and has been widely used in pain relief, inflammation regulation and wound healing. It is understood that about 20% of pet hospitals in North America use lasers for clinical treatment to achieve the purpose of regulating inflammation and accelerating healing.

Laser therapy is one of the key components of multimodal analgesia management, which relieves pain in sick animals through the following major mechanisms：

 

Conduction: The laser inhibits the pain conduction of Aδ and C fibers through mechanical stimulation and biological stimulation, thereby relieving pain.

l Inhibit the activation of kinin receptors in the inflammatory response and inhibit the secretion of bradykinin;

l Reduce the secretion of the pro-inflammatory factor interleukin-1;

l Reduce the level of prostaglandins in the body;

l Improve the level of nitric oxide in the body, promote vasodilation and the elimination of inflammatory mediators.

 

Transmission: Laser therapy can block the transmission of pain signals from afferent nerves to the spinal cord to a certain extent, and play a role in relieving pain.

l Inhibit the depolarization of C fibers;

l Increase the action potential threshold of nerve cells.

 

Modulation: Laser therapy can affect the transmission of pain signals from the dorsal horn of the spinal cord to the brain to a certain extent.

l Promote the production of β-endoceptide;

l Promote the production of the neurotransmitter acetylcholine (nicotinic choline receptor, nAChR) and inhibit nerve excitation.

 

Perception: Laser therapy can increase the secretion of serotonin——5-hydroxytryptamine (5-HT) in the body, affect the central nervous system's acceptance of pain signals, interfere with its processing of pain signals, and relieve the body's pain response.