**5. Research envisaged in an embolic stroke model**

Martin Andersen, MD et al., studied the effects of the combination of cytidine-59-diphosphocholine (citicoline) and thrombolysis using the embolic stroke model in rodents. Their studies found that the combination of rtPA (Recombinant tissue plasminogen activator) and a low dose of citicoline reduces infarct size in this model. This study also recommends further investigation to check the potential effects of this combination in treating ischemic stroke [45].

Karsten Overgaard et al., studied the effect of delayed thrombolysis with recombinant tissue plasminogen activator in an embolic stroke model. Their study found that infarct volume was significantly reduced by thrombolytic therapy and improved clinical score up to 2 h CAIdelay of treatment. They also found that treatment after 4 hr. may also be beneficial. Thus, delay in treatment may significantly increase the infarct volume and thrombolytic therapy in this model induced recanalization. The most significant advantage of this model was a few hemorrhage complications were seen [46].

D Lekieffre et al., have evaluated the efficacy of eliprodil in combination with the thrombolytic agent, rt-PA, in a rat embolic stroke model. Embolic stroke was induced by intracarotid injection of an arterial blood clot. Their study found that the use of elirodil alone or in combination with a thrombolytic agent reduced the extent of brain damage and neurological deficits in the embolized rat model. This study also confirmed that combined therapy of cytoprotective agent and thrombolytic agent produced effective neuroprotection and would be a new approach to treating stroke in humans [47].

Tomas Sereghy et al., studied the effects of excitatory amino acid receptor antagonist dizocilpine and alteplase and a combination of both in the embolic stroke model. In this model, the carotid artery was embolized using fibrin rich clots. Their research found that treatment with alteplase and dizocilpine reduced infarct volume individually, but combined treatment showed more promising results when compared to individual treatment. Combination treatment significantly reduced neuropathological changes after embolic stroke, and this combination would be a new therapeutic approach in humans for deep brain infarcts [48].

Rasmussen RS et al., studied the effects of d -amphetamine (d -amph) and physical therapy separately and combined on gross motor performance, cognition and acceptable motor performance using the embolic model in rats. Their studies

found no significant change in infarct volume, and no significant changes were seen in the gross performance. These results conclude that d -amphetamine (d -amph) improved cognitive functions, and physical therapy improved motor coordination in the embolic stroke model [49].
