[Adrenergic--sympathetic nervous apparatus of the cerebral arteries and its role in regulating cerebral circulation].

By means of fluorescence microscopy of catecholamines the authors studied the adrenergic innervation of cerebral arteries in mammals (dogs, cats, rabbits). It was demonstrated that the basis of a sympathic nervous apparatus of pial arteries in all animals is a well developed adrenergic plexus. In different calibre arteries of the pial membrane the nervous plexus differs significantly in its structure and degree of saturation of nerve fibers.

[Histochemical study of the vasomotor innervation of the internal carotid artery basin].

In the dog, the internal carotid artery and its branches were found to have a well developed nervous plexus with two kinds of nerve fibers: containing either active cholinesterase or catecholamines. In various segments of the basin, both the cholinergic and the adrenergic nerve fibers reveal structural and topographical differences depending on the structural and functional features of the vascular wall. The adrenergic and cholinergic nerve fibers are mainly situated in the adventitia of the internal carotid artery forming a terminal nervous plexus in deep portions, while in the vasa vasorum and in the siphon region they are terminated also in superficial layers of muscular coat.