Voluntary exercise increases neurotrophin-3 and its receptor TrkC in the spinal cord

• Published in: Brain research Vol. 987; no. 1; pp. 93 - 99
• Main Authors: Ying, Zhe, Roy, Roland R., Edgerton, V.Reggie, Gómez-Pinilla, Fernando
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 10.10.2003; Amsterdam Elsevier; New York, NY
• Subjects: Animals; Biological and medical sciences; Enzyme-Linked Immunosorbent Assay; Fundamental and applied biological sciences. Psychology; Male; Motor Activity; Neuromuscular activity; Neurotrophin; Neurotrophin 3 - genetics; Neurotrophin 3 - metabolism; NT-3; Physical Conditioning, Animal; Physical Exertion; Rats; Rats, Sprague-Dawley; Receptor, trkC - metabolism; RNA, Messenger - metabolism; Skeletal muscle; Space life sciences; Spinal cord; Spinal Cord - metabolism; TrkC; Up-Regulation; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Neurotrophin; TrkC; Spinal cord; Development and regeneration; Neuromuscular activity; NT-3; Skeletal muscle; Physical exercise; trkC receptor; Rat; Rodentia; Central nervous system; Striated muscle; Vertebrata; Mammalia; Non-programmatic
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/S0006-8993(03)03258-X

We have evaluated changes in the expression of neurotrophin-3 (NT-3) and its tyrosine kinase C (TrkC) receptor in the neuromuscular system as a result of voluntary physical activity. We assessed changes in the mRNAs and proteins for NT-3 and TrkC in the lumbar spinal cord and associated soleus muscle following 3 and 7 days of voluntary wheel running. We used quantitative Taqman RT-PCR to measure mRNA and ELISA to assess protein levels. NT-3 mRNA and protein levels increased in the spinal cord to reach statistical significance after 7 days of exercise compared to sedentary control rats. Immunohistochemical analyses localized the elevated NT-3 to the substantia gelatinosa (SG) and nucleus of the dorsal horn. TrkC mRNA levels were significantly elevated in the spinal cord after 3 and 7 days of running. In the soleus muscle, NT-3 mRNA levels and its receptor TrkC were elevated after 3 days, while NT-3 protein levels remained unaffected. The results demonstrate that voluntary exercise has a differential effect on NT-3 as well as its receptor TrkC in the neural and muscular components of the neuromuscular system, and emphasize the role of voluntary activity on the spinal cord and muscle.