Quantitative changes of the capillary bed in aging human skin.
The present study focuses on the quantitative changes of the capillary bed in aging human skin. Forty-five skin samples were excised from the anterior thoracic region of cadavers of caucasian origin in the age range 33-82 years. The immunohistochemical method with anti-human CD34 was used for the detection of the capillary endothelium. Morphometric analysis was done by Vision Assistant software. The capillary bed was quantified by two parameters: capillary area (CA) and intercapillary distance (ID) in 6 age groups. Results revealed no quantitative changes of the capillary bed up to the age of 60 years. In the papillary dermis a significant reduction of the capillary area was seen in the 7th, 8th and 9th decennium. A considerable decrease, by 33%, was determined in the 7th decennium. During the 8th and 9th decennium the capillary area was reduced by a further 19% and 13%. In total from the 4th till the 9th decennium, the capillary bed in the papillary dermis was diminished by 65%. The intercapillary distance in the papillary dermis singnificantly increased during the 8th decennium. On the basis of the mutual evaluation of both the observed parameters, CA and ICD, the authors supposed that the reduction of the capillary bed in the papillary dermis during the 7th decennium was probably caused only by the shortening of the capillary loops, which copied flattened dermal papillae, and during the 8th decennium also by the decreased number of the capillary loops. In the reticular dermis the capillary bed remained unchanged.