[Adrenergic innervation of the pial arteries of the human brain]

By means of glyoxylic acid adrenergic neural fibres have been studied in fetuses at the second part of pregnancy, in a 2-month-old boy, in a 18-year-old boy, in three men 30-, 34- and 40-year-old. According to the data of fluorescent microscopy, the fibres studied contain noradrenaline. In walls of the arteries 400 mkm and more in diameter there are double-layered adrenergic plexuses. In arteries of smaller diameter the adrenergic plexuses predominantly consist of longitudinal fibres. The adrenergic apparatus is situated within the external membrane; its development is more perfect in mature persons than in fetuses and in children before one year of age.