RUDN scientists showed that light therapy may increase blood pressure in case of hypertension

IMAGE: Experimental study of the effects of bright light with the use of telemetric monitoring technology carried out at V.A. Frolov Department of General Pathology and Pathological Physiology, Institute of Medicine,…
view more 

Credit: Courtesy of Mikhail Blagonravov.

Light therapy (phototherapy) is used to treat sleep disorders, depression, and seasonal mental disorders. In order to study its effects on the cardiovascular system (especially in case of stable increase in blood pressure) and to make phototherapy safer for patients suffering from hypertension, experts from RUDN University were carrying out experiments on rats for five months.

The experiments involved healthy animals and spontaneously hypertensive rats. In the animals of both groups blood pressure and heart rate were monitored during daytime and nighttime periods. For this purpose miniature devices monitoring blood pressure, ECG and motion activity continuously for 24 hours were implanted into the animal bodies. The animals lived in cages with a stable light pattern: 12 hours of complete darkness followed by 12 hours of light at the level of about 300 lux (similar to average office lighting). Then the scientists carried out a session of phototherapy increasing the light intensity level to 10,000 lux (similar to sunlight in dappled shade, for example, under a tree). Blood pressure and heart rate were registered for 24 hours on the day before the session (as a control measurement) and on the very day of bright light exposure.

Leave a Reply

Your email address will not be published. Required fields are marked *