Cerebral vasoreactivity in Andeans and headache at sea level.
Headache is common in Cerro de Pasco (CP), Peru (altitude 4338 m) and was present in all patients with chronic mountain sickness (CMS) in CP reported here. Forty-seven percent of inhabitants report headache. Twenty-four percent of men have migraine with aura, with an average of 65 attacks a year. We assessed vasoreactivity of the cerebral vessels to CO2 by rebreathing and to NO by the administration of isosorbite dinitrate (IDN), a nitric oxide (NO) donor, using transcranial Doppler ultrasound in the middle cerebral artery (MCA) in natives of CP, some of whom suffered from CMS. We repeated the measurements in Lima (altitude 150 m) in the same subjects within 24 h of arrival. Vasodilatation in the middle cerebral artery supply territory in response to CO2 and NO, both physiologic vasodilators, is defective in Andean natives at altitude and in the same subjects at sea level. Incapacitating migraine can occur with impaired cerebral vasoreactivity to physiologic vasodilators. We propose that susceptibility to migraine might depend in part on gene expression with consequent alterations of endothelial function.
Appenzeller
O
O
NMHEMC Research Foundation, Otto Appenzeller, 361, Big Horn Ridge Drive NE, Albuquerque, NM 87122-1424, USA. ottoarun12@aol.com
Passino
C
C
Roach
R
R
Gamboa
J
J
Gamboa
A
A
Bernardi
L
L
Bonfichi
M
M
Malcovati
L
L
D000531:Altitude; D000532:Altitude Sickness / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D002245:Carbon Dioxide / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000502:physiology*; D002908:Chronic Disease; D006801:Humans; D008297:Male; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000502:physiology; D020325:Migraine with Aura / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D009569:Nitric Oxide / Q000378:metabolism; D010568:Peru; D017585:Ultrasonography, Doppler, Transcranial
D002245:Carbon Dioxide; D009569:Nitric Oxide