title: Neural beta-adrenergic dilatation of the facial vein in man. Possible mechanism in emotional blushing.
abstract: Ring preparations of the superficial buccal segment of the human facial vein, taken from extirpated tissue in 12 patients during neck surgery, were studied in vitro. The vein developed a maintained intrinsic myogenic tone in response to passive stretch and was supplied with alpha- as well as beta-adrenoceptors, both of which could be influenced by transmural nerve stimulation (TNS) and noradrenaline. These unusual characteristics for a vein are basically similar to the ones described for the rabbit facial vein by Pegram, Bevan & Bevan (1976). In man there seemed to be an inter-individual difference with regard to the abundance of 'innervated' alpha- and beta-adrenoceptors. Facial vein specimens from some subjects thus responded with prompt and pronounced net dilatation to TNS with maximum at 4 Hz and those from others with net constriction with maximum at 16 Hz. The latter showed a reversal into neural beta-adrenergic dilatation after alpha-adrenergic blockade. The human external jugular vein was devoid of intrinsic tone and beta-adrenoceptors. It is tentatively proposed that a beta-adrenergic neuro-effector mechanism in superficial ramifications of the facial vein in man might be involved in the emotional blushing reaction.
mesh_terms: D000328:Adult; D000368:Aged; D001821:Blushing / Q000502:physiology*; D004558:Electric Stimulation; D005145:Face / Q000098:blood supply*; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000494:pharmacology; D010812:Physical Stimulation; D011941:Receptors, Adrenergic / Q000502:physiology*; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D014664:Vasodilation; D014680:Veins / Q000187:drug effects / Q000294:innervation
chemical_list: D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D007545:Isoproterenol; D009638:Norepinephrine