Pharmacological alterations after clot removal in monkey chronic cerebral vasospasm.
An autologous blood clot was placed bilaterally around cerebral arteries in the basal subarachnoid space to mimic subarachoid haemorrhage (SAH). Cynomolgus monkeys were randomised into five groups: sham operated groups, clot removal group at 48, 72 or 96 h after. SAH and clot group. The proximal parts of the middle cerebral arteries were cut into rings for isometric tension measurements at 7 days after SAH. Potassium chloride, 5-hydroxytryptamine (5-HT), norepinephrine (NE), adenosine triphosphate (ATP), prostaglandin F(2alpha) (PGF(2alpha)) and haemoglobin all induced dosed-dependent contractions. There was a progressive attenution of the contractions in response to the agonists in the clot removal and the clot groups, which reached statistical significance at 48 h after SAH in the case of 5-HT, and at 72 h in the cases of NE, ATP and PGF(2alpha) as compared with the sham operated group. These pharmacological results suggest that clot removal should within the first two days after SAH to prevnt cerebral vasospasm.
Tsuji
T
T
Department of Neurosurgery, Shinshu University, Matsumoto, Japan.
Cook
D A
DA
Weir
B K
BK
Handa
Y
Y