The course of vasospasm following subarachnoid haemorrhage in rats

Abstract

The course of vasospasm following subarachnoid haemorrhage in rats was studied using vertebrobasilar angiography. Wistar and Sprague Dawley rats were compared with respect to vasospastic response after bleeding. A more pronounced vasospasm was found in Sprague Dawley rats. In order to avoid a possible toxic effect on the contrast medium, only one angiogram per animal was initially performed. However, a comparison with the results obtained in a separate series of non-challenged animals demonstrated a difficulty due to high variability in basilar artery size in the latter group. Therefore, vasospasm can be more readily shown if multiple angiograms are used in the same animal so that the vasospasm can be expressed as a percentage of the initial diameter of the basilar artery. It was found that multiple angiograms are well tolerated when non-ionic contrast media are used.

Hypothermia Reduces Acute Vasospasm Following SAH in Rats

“…As hypothermia decreases metabolism, if the latter was the case, a more pronounced hypoperfusion should be present in hypothermic animals. Additionally, several authors have demonstrated angiographic vasoconstriction 10 minutes following experimental SAH, which has been termed acute vasospasm and has been physiologically interpreted as an attempt to seal the rupture site [3,10]. In summary, current data as well as our results show, that SAH induces a potent vasoconstriction lasting several hours.…”

Time Course in the Development of Cerebral Vasospasm after Experimental Subarachnoid Hemorrhage: Clinical and Neuroradiological Assessment of the Rat Double Hemorrhage Model

“…The earlier deficits (on Day 2 and 3) may be an expression of the SAH resulting initially in a transient increased intracranial pressure and a reduced CBF (6,10,45,48,56). The neurological recovery of the rats seemed to be prevented by the development of delayed CVS.…”

“…The difficulty in angiographic investigations of rat cerebral arteries because of the small vessel size has been discussed previously and several techniques have been investigated (5,10,18,24,32,56). Selective catheterization of the VA (56) shows the highest resolution in imaging the BA (25,32) but contains a higher risk of cardiac abnormalities caused by the contrast medium usually after multiple angiographies (56).…”

Cerebral Artery Remodeling in Rodent Models of Subarachnoid Hemorrhage

“…Several previous studies used Sprague Dawley rats in SAH studies, while our study investigated Wistar rats. One study found vasospasm in male Sprague Dawley rats but not in Wistar rats following cisterna magna-injected blood-induced SAH [49]. This leaves the possibility that in the former strain of rats structural changes would also have been seen under the current protocol.…”