Low power laser irradiation enhances migration and neurite sprouting of cultured rat embryonal brain cells.

We used fetal brain cells grown in tissue culture to study some basic features of the interaction between low-power laser irradiation and biological systems. Seven- to nine-day-old rat fetal brain cell aggregates in culture were subjected to direct focused irradiation of low-power helium-neon laser (0.3 mW, 632.8 nm). An 8-minute dose of laser irradiation enhanced the appearance of brain cells around the treated aggregates, as monitored under the microscope of the stained cultures. Two and three doses of laser irradiations were correlated with 97% and 142% respective increases of the numbers of cells surrounding the aggregates. To identify the type of cells grown in the outgrowth of the treated aggregate, specific tetanus-anti-tetanus antibodies were used. Rhodamine-labeled antibodies bound to receptors on cells indicated massive neurite sprouting and outgrowth of migrating brain cells in culture.