TY - JOUR
T1 - Reintroduction of the Rat for Experimental Subarachnoid Hemorrhage with Accelerated Clot Formation
T2 - A Low Mortality Model with Persistent Clots as a Precondition for Studies in Vasospasm
AU - Ehlert, Angelika
AU - Budde, Ulrich
AU - Middendorff, Ralf
AU - Manthei, Gerd
AU - Kemmling, Andre
AU - Tiemann, Bastian
PY - 2018/7/4
Y1 - 2018/7/4
N2 - Background Cerebral vasospasm as a delayed, possibly treatable sequel of subarachnoid hemorrhage (SAH) is a focus of experimental animal research. For this purpose, the rat is not a good model because of the difficulty creating a stable subarachnoid clot that persists > 1 to 2 days and could induce vasospasm. Only in rat models with a high mortality of ∼ 50% or more can SAH and its effects be investigated. Therefore, other animals than rodents are used for investigating the delayed effects of SAH. Only animal studies addressing the acute effects of SAH use rats. Objective We designed a model that allows intensive clot formation combined with low mortality to facilitate studies on the delayed effects of experimental SAH, for example, delayed vasospasm or other alterations of vessels. Methods After in vitro acceleration of the clotting process in the rats' blood by tissue factor and preliminary in vivo testing, we induced a SAH by injecting blood together with tissue factor in 22 rats. We analyzed clot expansion, length of clot persistence, chronic alterations, and histologic changes. Results The injection of blood supplemented by tissue factor led to persistent voluminous blood clots in the subarachnoid space close to the large arteries. Despite the pronounced SAH, all animals survived, allowing investigation of delayed SAH effects. All animals killed within the first 7 days after surgery had extensive clots; in some animals, the clots remained until postoperative day 12. During further clot degradation connective tissue appeared, possibly as a precursor of SAH-related late hydrocephalus. Conclusion The injection of blood together with tissue factor significantly improves SAH induction in the rat model. This rat model allows studying delayed SAH effects as found in humans.
AB - Background Cerebral vasospasm as a delayed, possibly treatable sequel of subarachnoid hemorrhage (SAH) is a focus of experimental animal research. For this purpose, the rat is not a good model because of the difficulty creating a stable subarachnoid clot that persists > 1 to 2 days and could induce vasospasm. Only in rat models with a high mortality of ∼ 50% or more can SAH and its effects be investigated. Therefore, other animals than rodents are used for investigating the delayed effects of SAH. Only animal studies addressing the acute effects of SAH use rats. Objective We designed a model that allows intensive clot formation combined with low mortality to facilitate studies on the delayed effects of experimental SAH, for example, delayed vasospasm or other alterations of vessels. Methods After in vitro acceleration of the clotting process in the rats' blood by tissue factor and preliminary in vivo testing, we induced a SAH by injecting blood together with tissue factor in 22 rats. We analyzed clot expansion, length of clot persistence, chronic alterations, and histologic changes. Results The injection of blood supplemented by tissue factor led to persistent voluminous blood clots in the subarachnoid space close to the large arteries. Despite the pronounced SAH, all animals survived, allowing investigation of delayed SAH effects. All animals killed within the first 7 days after surgery had extensive clots; in some animals, the clots remained until postoperative day 12. During further clot degradation connective tissue appeared, possibly as a precursor of SAH-related late hydrocephalus. Conclusion The injection of blood together with tissue factor significantly improves SAH induction in the rat model. This rat model allows studying delayed SAH effects as found in humans.
UR - http://www.scopus.com/inward/record.url?scp=85049597121&partnerID=8YFLogxK
U2 - 10.1055/s-0038-1641561
DO - 10.1055/s-0038-1641561
M3 - Journal articles
AN - SCOPUS:85049597121
VL - 79
SP - 424
EP - 433
JO - Journal of Neurological Surgery, Part A: Central European Neurosurgery
JF - Journal of Neurological Surgery, Part A: Central European Neurosurgery
SN - 2193-6315
IS - 5
ER -