Immunohistochemical distribution of irisin in the lung and tongue of Porcupine (Hystrix cristata)

Irisin, a novel peptide, was first identified in skeletal muscle cells. It is an exercise protein that is secreted into the bloodstream,through which it reached the white adipose tissue, and interacted with an unknown receptor and cause fat destruction byconverting the white adipose tissue to brown adipose tissue. The presence of irisin immunoreactivity in porcupine lung andtongue was studied. In lung, irisin immunoreactivity was found in type II pneumocytes,qa bronchus, bronchioles and bloodvessel. Positive irisin immunostaining was also detected in the lamina epithelialis, striated muscle cells and serous glandsin porcupine’s tongue. The function of locally synthesized irisin is currently unknown. Therefore, further study is requiredto reveal the precise effect of irisin