Neurotransmitter-Loaded Nanocapsule Triggers On-Demand Muscle Relaxation in Living Organism

• Published in: ACS applied materials & interfaces 2018-11, Vol.10 (44), p.37812-37819
• Main Authors: Le, Duc Long, Ferdinandus, Tnee, Chin Kiat, Vo Doan, T. Thang, Arai, Satoshi, Suzuki, Madoka, Sou, Keitaro, Sato, Hirotaka
• Format: Article
• Language: English
• Subjects: Animals; Coleoptera - drug effects; Coleoptera - radiation effects; Drug Carriers - administration & dosage; Drug Carriers - chemistry; Electric Stimulation; gamma-Aminobutyric Acid - administration & dosage; gamma-Aminobutyric Acid - chemistry; Humans; Liposomes - administration & dosage; Liposomes - chemistry; Muscle Relaxation - drug effects; Muscle Relaxation - radiation effects; Muscle, Skeletal - drug effects; Muscle, Skeletal - radiation effects; Nanocapsules - administration & dosage; Nanocapsules - chemistry; Neurotransmitter Agents - administration & dosage; Neurotransmitter Agents - chemistry
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.8b11079

This paper reports the on-demand artificial muscle relaxation using a thermosensitive liposome encapsulating γ-aminobutyric acid (GABA) inhibitory neurotransmitter. Muscle relaxation is not feasible in principle, although muscle contraction can be easily induced by electrical stimulation. Herein, thermosensitive liposomes (phase transition temperature = 40 °C) were synthesized to encapsulate GABA and were injected into a leg of a living beetle. The leg was wrapped around by a Ni–Cr wire heater integrated with a thermocouple to enable the feedback control and to manipulate the leg temperature. The injected leg was temporarily immobilized by heating it up to 45 °C. The leg did not swing even by electrically stimulating the leg muscle. Subsequently, the leg recovered to swing. The result indicates that GABA was released from liposomes and fed to the leg muscle, enabling temporal muscle relaxation.