Objective: To investigate the effect of repetitive magnetic stimulation of the spinal cord on limb angiogenesis in healthy rats and explore its implication for the treatment of lymphedema.

Methods: Twelve adult male Sprague-Dawley rats were divided into four groups as follows: sham repetitive magnetic stimulation (rMS) followed by tissue harvest 5 minutes later (group 1, n=2), 1 Hz rMS and tissue harvest 5 minutes later (group 2, n=3), 20Hz rMS and tissue harvest 5 minutes later (group 3, n=3), 20Hz rMS and tissue harvest 30 minutes later (group 4, n=4). Animals were treated with 20-minute rMS with 120% of the motor threshold on their left side of upper lumbar spinal cord. Expression of angiogenic factors, that is, Akt, phospho-Akt, endothelial nitric oxide synthase (eNOS), phospho-eNOS were measured by Western blot. Bilateral hindlimb muscles (quadriceps and gastrocnemius) were harvested.

Results: Expression of eNOS in quadriceps muscle was markedly increased in group 3 and 4 (6.4 and 7.7-fold each compared with group 1, p=0.04). Also, expression of eNOS in gastrocnemius muscle was increased in group 2 and 3 than in group 1 (p=0.02). Expression of Akt in gastrocnemius muscle tends to increase in rMS- treated groups than in sham rMS group (p>0.05). Expression of phospho-Akt and phospho-eNOS were not comparable between four groups (p>0.05).

Conclusion: Repetitive magnetic stimulation of the spinal cord may exert an angiogenic effect closely linked to lymphangiogenesis. It has clinical implication for the possible therapy of lymphedema caused by breast, cervical or endometrial cancer operation. Future studies with the specific lymphatic endothelial cell markers are required to confirm the effect of repetitive magnetic stimulation on lymphangiogenesis.

Citation Information: Clin Cancer Res 2010;16(14 Suppl):A47.