Age related structural changes in human basilar artery
Keywords: basilar artery, collagen fibers, media thickness, smooth muscle cells
AbstractThe basilar artery is the most important artery in the posterior cerebral circulation. In the cases of stroke due to acute basilar artery occlusion the mortality rate is significantly higher if compared to all the stroke cases. Arterial wall stiffening is characteristic of ageing arteries and in many investigations arterial wall stiffening is related to the loss of the elastic component in the arterial wall during ageing. In arterial stiffening the changes in the collagen content and the number of smooth muscle cells (SMC) may also play a role. Basilar arteries were obtained within 24 hours postmortem from 89 human cadavers (44 male and 45 female). From the middle part of the basilar arteries histological slides were performed and area of collagen fibers, the number of smooth muscle cells and the thickness of the media were measured. The morphometric analysis revealed the increase of collagen network area with the age. Analysing age-related changes in the number of SMC in male and female basilar artery media, we determined that in both genders the number of SMC in the media decreased. Changes in SMC number in both genders had a strong negative correlation with the age (r=–0.93 in the male group and r=–0.95 in the female group, respectively). In the analysis of the media thickness in different gender and age groups, its thickening was determined. The correlation with the age was of medium strength both in the male (r=0.36) and female (r=0.4) group. In all the cases this correlation was statistically significant (p<0.05). Our morphometric findings that revealed the increased collagen area together with the decrease of the SMC number might be responsible for the stiffening of the basilar artery in aging and contribute to the development of atherosclerosis and arterial hypertension.