Abstract
Purpose: :
To compare the diameter response of macular and peripheral arterioles in healthy young persons after an increase in the arterial blood pressure induced by isometric exercise.
Methods: :
Thirteen healthy young males (mean age 28.2 years, range 25-34 years) were examined. Using a Retinal Vessel Analyzer (RVA) the diameter response of a macular and a peripheral arteriole located within four disk diameters of the optic disk was recorded in each person before and after increasing the blood pressure by lifting a 2 kg hand weight.
Results: :
There was no significant difference between the baseline diameter of the studied macular(97.3±3.3) and peripheral (101.2±3.4) arterioles (p=0.44). Lifting the hand weight increased the arterial blood pressure significantly (18.5±1.7) mmHg, and induced a significant contraction of the retinal arterioles (p<0.0001). The diameter response in the macular arterioles (3.93±0.89) was significantly higher than the diameter response in the peripheral arterioles (2.28±0.65), p =0.01.
Conclusions: :
The diameter response of retinal arterioles after an increase in the blood pressure induced by isometric exercise is significantly higher in macular than in peripheral arterioles. This may contribute to the differences in the distribution of retinal lesions observed in the macular area and the retinal periphery in retinal vascular disease.
Keywords: blood supply • protective mechanisms • retina