Changing growth of neurites of sensory ganglion by terahertz radiation M.V. Tsurkan* a , O.A. Smolyanskaya a , V.G. Bespalov a , V.A. Penniyainen b , A.V. Kipenko b,c , E.V.Lopatina b,c , B.V. Krylov b a The National Research University of Information Technologies, Mechanics and Optics, St.Petersburg, Russia; b Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg, Russia; c Almazov Federal Heart, Blood and Endocrinology Centre, St. Petersburg, Russia; ABSTRACT Application of terahertz radiation for the creation of medical equipment and solving of biological problems has become widely spread. From this point of view, the influence of THz radiation on the nerve fibers is of primary concern. In addition, several studies indicated both stimulating and depressive effects on nerve cells. However, the mechanism of this effect has not yet been studied, including the dose and exposure time. Our research was devoted to the impact of broadband pulsed THz radiation in the frequency range of 0.05 to 2 THz on the neurite growth in the sensory ganglia of 10-12-day chicken embryos. Dependence of changes in functional responses of cells on the average output power has been found. An increase in the stimulating effect was observed at the lowest power density used (0.5 μW/cm 2 ). Through non-destructive process and choosing the correct parameters of THz radiation, potential control of neural response becomes possible, which can subsequently lead to new medical treatments. Keywords: Terahertz radiation, organotypic tissue culture, cell growth, medicine, therapy 1. INTRODUCTION The terahertz radiation, as part of the electromagnetic spectrum, is located between the microwave and the infrared radiation and refers to a frequency range from 0.01 to 10 THz. It corresponds to wavelengths from 30 μm to 3 mm. With relatively low photon energy of 0.41 to 41 meV, radiation within this frequency range is considered non-ionizing. The recent development of new sources to generate terahertz radiation with high spectral sensitivity and resolution allowed the creation of new technologies for the military industry and security systems, as well as in the fields of biology, chemistry and medicine (1). The peculiarity of the terahertz radiation lies in the fact that a significant part of the vibrational-rotational spectrum of water and many organic molecules including biologically active macromolecules (i.e. proteins and nucleic acids), as well as the frequencies of intermolecular interactions are located in its frequency range. In connection with this, most researches deal with the application of THz radiation in the far infrared spectrum, where a large number of absorption lines exist. They are mainly related to the development of methods of spectral studies of molecules. It was shown that complex biological molecules, including DNA and RNA, also exhibit absorption in the terahertz frequency range (2-7). Currently a large number of scientific works is devoted to studying a possible use of the terahertz technology for medical imaging, including diagnosis of the skin cancer, cardiovascular diseases and diseases of the teeth (8-16). The use of sources of terahertz (THz) radiation in various fields, including biology and medicine is increasing every year. At the same time the need for better understanding of the mechanisms of the interactions and their potential is increasing as well. Both positive and negative effects are relevant. This is reflected in an increasing number of works, related to the study of possible effects that are caused by the absorption of THz radiation by various biological objects at different levels of biological organization. Many studies were conducted in the framework of a large-scale European project called Terahertz Technology and Applications V, edited by Laurence P. Sadwick, Créidhe M. O'Sullivan, Proc. of SPIE Vol. 8261, 82610S · © 2012 SPIE · CCC code: 0277-786X/12/$18 · doi: 10.1117/12.909350 Proc. of SPIE Vol. 8261 82610S-1 Downloaded from SPIE Digital Library on 21 Mar 2012 to 81.94.20.12. Terms of Use: http://spiedl.org/terms