Effect of calcitonin gene-related peptide on delayed cerebral vasospasm after experimental subarachnoid hemorrhage in rabbits.
BACKGROUND
Calcitonin gene-related peptide (CGRP) is an intrinsic vasodilatory substance contained in perivascular nerve fibers of intracranial arteries. It is suggested that CGRP plays a role in cerebral vasospasm after subarachnoid hemorrhage (SAH).


METHODS
An experimental SAH was produced by intracisternal injection of arterial blood in rabbits. The animals were treated with intrathecal administration of CGRP solution 3 days after SAH. The degree of vasospasm and the effect of CGRP were evaluated angiographically by measuring the basilar artery diameter.


RESULTS
The basilar artery constricted to 73.0% of the pre-SAH values 3 days after SAH. Fifteen minutes after injection of 10(-10) mol/kg CGRP, the basilar artery dilated to 117.1% (n = 8), which was significantly larger than 67.1% in the vehicle group (n = 8) (p < 0.01). The significant vasodilatory effect of CGRP, compared with the vehicle group, lasted for 6 hours.


CONCLUSIONS
Intrathecal administration of CGRP has therapeutic potential for treating cerebral vasospasm.
Imaizumi
S
S
Department of Neurosurgery, Isawa Prefectural Hospital, Mizusawa, Japan.
Shimizu
H
H
Ahmad
I
I
Kaminuma
T
T
Tajima
M
M
Yoshimoto
T
T
D000818:Animals; D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D015740:Calcitonin Gene-Related Peptide / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D004195:Disease Models, Animal; D007278:Injections, Spinal; D002546:Ischemic Attack, Transient / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D011817:Rabbits; D011859:Radiography; D013345:Subarachnoid Hemorrhage / Q000150:complications*; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects*; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*
D014665:Vasodilator Agents; D015740:Calcitonin Gene-Related Peptide