title: Failure to demonstrate a vasoconstrictive effect of vasopressin on the internal carotid and middle cerebral arteries: a transcranial ultrasound Doppler study.
abstract: Vasopressin (AVP) was infused into four healthy human volunteers to explore by Doppler ultrasound the vasoconstrictive action of AVP on the internal carotid (ICA) and the medial cerebral artery (MCA, transcranial Doppler technique). Although AVP levels rose to 74.2 pg/ml (+/- 13 pg, SEM) no significant changes of flow velocity were observed in the ICA as well as the MCA. There was no effect on the pulsatility index of the MCA velocity profile indicating that peripheral vascular resistance remained unchanged during AVP infusion. These results do not support an effect of AVP at high physiological levels on the vascular diameters of the ICA, MCA and cerebral arteriolar system in humans.
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects; D002343:Carotid Artery, Internal / Q000187:drug effects*; D002536:Cerebral Arteries / Q000187:drug effects*; D006801:Humans; D008297:Male; D012212:Rheology; D014661:Vasoconstriction / Q000187:drug effects*; D014667:Vasopressins / Q000494:pharmacology*
chemical_list: D014667:Vasopressins