TY - JOUR
T1 - Cerebral haemodynamic response or excitability is not affected by sildenafil
AU - Kruuse, Christina
AU - Hansen, Adam E
AU - Larsson, Henrik B W
AU - Lauritzen, Martin
AU - Rostrup, Egill
PY - 2009/4
Y1 - 2009/4
N2 - Sildenafil (Viagra), a cyclic guanosine monophosphate-degrading phosphodiesterase 5 inhibitor, induces headache and migraine. Such headache induction may be caused by an increased neuronal excitability, as no concurrent effect on cerebral arteries is found. In 13 healthy females (23+/-3 years, 70.3+/-6.6 kg), the effect of sildenafil on a visual (reversing checkerboard) and a hypercapnic (6% CO2 inhalation) response was evaluated using functional magnetic resonance imaging (fMRI, 3 T MR scanner). On separate occasions, visual-evoked potential (VEP) measurements (latency (P100) and maximal amplitude) were performed. The measurements were applied at baseline and at both 1 and 2 h after ingestion of 100 mg of sildenafil. Blood pressure, heart rate and side effects, including headache, were obtained. Headache was induced in all but one subject on both study days. Sildenafil did not affect VEP amplitude or latency (P100). The fMRI response to visual stimulation or hypercapnia was unchanged by sildenafil. In conclusion, sildenafil induces mild headache without potentiating a neuronal or local cerebrovascular visual response or a global cerebrovascular hypercapnic response. The implication is that sildenafil-induced headache does not include a general lowering of threshold for a neuronal or cerebrovascular response, and that sildenafil does not modulate the hypercapnic response in healthy subjects.
AB - Sildenafil (Viagra), a cyclic guanosine monophosphate-degrading phosphodiesterase 5 inhibitor, induces headache and migraine. Such headache induction may be caused by an increased neuronal excitability, as no concurrent effect on cerebral arteries is found. In 13 healthy females (23+/-3 years, 70.3+/-6.6 kg), the effect of sildenafil on a visual (reversing checkerboard) and a hypercapnic (6% CO2 inhalation) response was evaluated using functional magnetic resonance imaging (fMRI, 3 T MR scanner). On separate occasions, visual-evoked potential (VEP) measurements (latency (P100) and maximal amplitude) were performed. The measurements were applied at baseline and at both 1 and 2 h after ingestion of 100 mg of sildenafil. Blood pressure, heart rate and side effects, including headache, were obtained. Headache was induced in all but one subject on both study days. Sildenafil did not affect VEP amplitude or latency (P100). The fMRI response to visual stimulation or hypercapnia was unchanged by sildenafil. In conclusion, sildenafil induces mild headache without potentiating a neuronal or local cerebrovascular visual response or a global cerebrovascular hypercapnic response. The implication is that sildenafil-induced headache does not include a general lowering of threshold for a neuronal or cerebrovascular response, and that sildenafil does not modulate the hypercapnic response in healthy subjects.
KW - Adult
KW - Cerebrovascular Circulation/drug effects
KW - Evoked Potentials, Visual
KW - Female
KW - Headache/chemically induced
KW - Hemodynamics/drug effects
KW - Humans
KW - Hypercapnia
KW - Magnetic Resonance Imaging
KW - Photic Stimulation
KW - Piperazines/adverse effects
KW - Purines/adverse effects
KW - Sildenafil Citrate
KW - Sulfones/adverse effects
KW - Young Adult
U2 - 10.1038/jcbfm.2009.10
DO - 10.1038/jcbfm.2009.10
M3 - Journal article
C2 - 19209179
SN - 0271-678X
VL - 29
SP - 830
EP - 839
JO - Journal of Cerebral Blood Flow and Metabolism
JF - Journal of Cerebral Blood Flow and Metabolism
IS - 4
ER -