[Changes in adrenergic innervation of the choroid during aging].

Background: Aging causes loss of neurons and adrenergic nerve termination in various human organism systems and apparatus. The aim of this work is the observation of qualitative and quantitative differences in the orientation and density of the human choroid adrenergic innervation in relation to age.
Methods: The choroid specimens were taken from the corresponding sectors of the eyeballs of four patients aged between 70 and 75 years and patients aged between 40 and 45 years. The glyoxilic method of Furness and Costa (1975) was used.
Results: The location and orientation of the adrenergic fibres was similar in the adult and aged patients. However, the fibres are clearly fewer in number, less rich in varicosity and have reduced fluorescence. In the suprachoroid lamina thickness and in the vascular layer, the adrenergic synaptic contacts with the melanocytes are fewer in number, as are also the SIF-cells (small intensely fluorescent cells).
Conclusions: With age there is a significant reduction of the orthosympathetic innervation of the human choroid. This fact could explain some physiopathological aspects of the choroid circulation and blood flow and, therefore, play a part in ocular pression variations.