Danish Headache Study
The Effect of Circulating Adenosine on Cerebral Haemodynamics and Headache Generation in Healthy Subjects
Background and Purpose
Adenosine is anogenous neurotransmitter that is released from the brain during hypoxia and relaxes isolated human cerebral arteries. Many cerebral artery dilators cause migraine attacks. However, the effect of intravenous adenosine on headache and cerebral artery diameter has not previously been investigated in man and reports regarding the effect of intravenous adenosine on cerebral blood flow are conflicting.
Methods
Twelve healthy participants received adenosine 80, 120 µg kg-1 min-1 and placebo intravenously for 20 min, in a double-blind, three-way, crossover, randomised design. Headache was rated on a verbal scale (0-10). Regional cerebral blood flow (rCBF) with 133Xe inhalation and single-photon emission computed tomography (SPECT) and MCA flow velocity (VMCA) with transcranial Doppler, were measured in direct sequence.
Baseline Values ± SD
| Placebo | Adenosine 80 µg kg-1 min-1 | Adenosine 120 µg kg-1 min-1 | |
|---|---|---|---|
| Baseline values for middle cerebral artery flow velocity (VMCA),-tidal partial pressure of CO2 (PetCO2), blood pressure (BP) and other variables before the infusion of placebo, adenosine 80 µg kg-1 min-1 or 120 µg kg-1 min -1 | |||
| VMCA (cm s-1) | 73 ± 8 | 72 ± 9 | 70 ± 8 |
| Temporal art diameter (mm) | 1.43 ± 0.34 | 1.43 ± 0.34 | 1.43 ± 0.33 |
| PetCO2 (mmHg) | 37.7 ± 1.0 | 38.6 ± 0.9 | 37.9 ± 0.8 |
| BP, systolic (mmHg) | 117 ± 19 | 118 ± 8 | 118 ± 15 |
| BP, diastolic (mmHg) | 67 ± 17 | 68 ± 12 | 66 ± 12 |
| Heart rate (min-1)59 | 59 ± 8 | 58 ± 7 | 58 ± 11 |
| Plasma adenosine (µM) | 0.64 ± 0.75 | 0.96 ± 1.28 | 0.66 ± 0.65 |
