caa a22 4500 477113001 CHVBK 20180405111615.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF01744506 doi (NATIONALLICENCE)springer-10.1007/BF01744506 Effect of clot removal on cerebrovascular contraction after subarachnoid hemorrhage in the monkey: Pharmacological study [Elektronische Daten] [Tsutomu Tsuji, David Cook, Bryce Weir, Yuji Handa] Summary: Clot removal at early surgery has been reported to be clinically effective for the prevention of cerebral vasospasm following subarachnoid hemorrhage (SAH) due to rupture of an intracranial aneurysm. We examined the most efficacious timing of mechanical clot removal on pharmacological responses in a monkey SAH model. Cynomolgus monkeys (Macaca fascicularis) were randomized into five groups: sham-operated, clot removal in which the clot was removed 48, 72, or 96h after SAH, and clot groups. An autologous blood clot was placed around the bilateral major cerebral arteries after craniectomy to mimic the hemorrhage. Seven days after the SAH, proximal and successively distal parts of the middle cerebral arteries were cut into rings for isometric tension measurement. The contractile responses to potassium chloride, 5-hydroxytryptamine, norepinephrine, adenosine triphosphate, prostaglandin F2α, and hemoglobin were greater in the proximal parts than in the distal parts in each group. Compared with the sham-operated group, the responses of the clot-removal and clot groups to the drugs were progressively attenuated. The maximum responses to 5-hydroxytryptamine in the proximal parts and to adenosine triphosphate in the distal parts started to decrease, significantly, in the clot-removal group 48h after SAH, while most of the responses to the other agonists began to decrease in the clot-removal groups later than 72h after SAH. These results suggest that the attenuation of cerebrovascular contractile responses 7 days after SAH is pharmacologically inevitable, even if the clot is removed as early as 48h after the SAH. Clot removal may thus be recommended within 48h after SAH to ameliorate the severity of cerebral vasospasm following SAH. Springer-Verlag, 1996 Vascular contraction nationallicence Clot removal nationallicence Subarachnoid hemorrhage nationallicence Cerebral vasospasm nationallicence Tsuji Tsutomu Department of Neurosurgery, Shinshu University School of Medicine, 3-1-1 Asahi, 390, Matsumoto, Japan aut Cook David Department of Pharmacology, Faculty of Medicine, University of Alberta, T6G 2B7, Edmonton, Alberta, Canada aut Weir Bryce Section of Neurosurgery, The University of Chicago Medical Center, 60637, Chicago, IL, USA aut Handa Yuji Department of Neurosurgery, Fukui Medical School, 910-11, Matsuoka, Fukui, Japan aut Heart and Vessels Springer-Verlag 11/2(1996-03-01), 69-79 0910-8327 11:2<69 1996 11 380 https://doi.org/10.1007/BF01744506 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01744506 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tsuji Tsutomu Department of Neurosurgery, Shinshu University School of Medicine, 3-1-1 Asahi, 390, Matsumoto, Japan aut NATIONALLICENCE 700 1- Cook David Department of Pharmacology, Faculty of Medicine, University of Alberta, T6G 2B7, Edmonton, Alberta, Canada aut NATIONALLICENCE 700 1- Weir Bryce Section of Neurosurgery, The University of Chicago Medical Center, 60637, Chicago, IL, USA aut NATIONALLICENCE 700 1- Handa Yuji Department of Neurosurgery, Fukui Medical School, 910-11, Matsuoka, Fukui, Japan aut NATIONALLICENCE 773 0- Heart and Vessels Springer-Verlag 11/2(1996-03-01), 69-79 0910-8327 11:2<69 1996 11 380 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer