Mori T, Nagata K, Ishida T, Nikaido H, Kobayashi E, Sasaki T, Ohami H, Kirino T
Division of Pathology, Institute of Gerontology, Nippon Medical School, Kanagawa, Japan.
J Vet Med Sci. 1994 Jun;56(3):535-40. doi: 10.1292/jvms.56.535.
To demonstrate the possible role of foreign-body reaction to extravasated blood in provoking chronic cerebral vasospasm, talc (crystallized hydrous magnesium silicate) was injected as a non-biologic foreign material into the canine-cisterna cerebellomedullaris, and pathologic changes were followed. Angiographically, this cisternal talc injection induced delayed and prolonged constriction of the basilar artery, without any evidence of so-called early phase cerebral vasospasm that should occur shortly after an insult. Pathologically, around the spastic artery in the subarachnoid space with talc injection, the appearance of a moderate cellular migration coincided with cerebral vasoconstriction, which took place 2 days after the talc injection. In the spastic basilar arterial wall, marked constrictive and degenerative changes including myonecrosis and subintimal proliferation were induced by cisternal talc injection as early as on day 2, and the changes were progressive with time. These pathologic changes were extremely analogous to those of the human autopsy cases with chronic cerebral vasospasm (chronic VS) but more prominent than those observed in the experimental autologous blood-induced model. The present study demonstrated that a foreign-body reaction to talc alone could induce chronic VS in the absence of extravasated blood. Thus, it is possible to consider that inflammatory reactions to extravasated autologous blood in subarachnoid hemorrhage may give rise to chronic VS.
为了证明异物对渗出血液的反应在引发慢性脑血管痉挛中可能起到的作用，将滑石粉（结晶水合硅酸镁）作为一种非生物性异物注入犬小脑延髓池，并观察其病理变化。血管造影显示，这种小脑延髓池内注射滑石粉可导致基底动脉延迟和持续收缩，没有任何证据表明在损伤后不久会出现所谓的早期脑血管痉挛。病理检查发现，在注射滑石粉后的蛛网膜下腔中，痉挛动脉周围在注射滑石粉2天后出现中等程度的细胞迁移，同时伴有脑血管收缩。在痉挛的基底动脉壁上，早在第2天，小脑延髓池内注射滑石粉就可诱导明显的收缩性和退行性改变，包括肌坏死和内膜下增殖，且这些改变随时间进展。这些病理变化与慢性脑血管痉挛（慢性VS）的人类尸检病例极为相似，但比在实验性自体血诱导模型中观察到的更为明显。本研究表明，仅对滑石粉的异物反应在没有血液渗出的情况下也可诱导慢性VS。因此，可以认为蛛网膜下腔出血时对渗出的自体血的炎症反应可能会导致慢性VS。
