Effect Of Artificial Cold Exposure On Ischemic Stroke And Prophylactic Effect Of Nimodipine On It

Objective:To study the effect of artificial cold exposure(ACE) on the ischemic stroke in carotid atherosclerotic rats, and the prophylactic effect of nimodipine on it .Methods:130 SD rats were randomly divided into normal group(10), sham operated group(10), and carotid atherosclerotic (CAS) group(110). Then the CAS group was further divided to three subgroups: non-ACE group, ACE group and nimodipine group. All the groups were subjected to ACE except non-ACE group. During the ACE nimodipine was administrated intragastrically to the rats in the nimodipine group and the same volume of NS in the ACE group. Then the change of the blood pressure and the blood serum of thrombomodulin (TM), p-selectin, endothelin-1 (ET-1) and nitric oxide (NO) was analyzed before and after ACE. And the incidence of ischemic stroke was observed.Results:â‘ The blood pressure pre-ACE of sham operated group and carotid atherosclerotic group were significantly higher than normal group(p<0.05). Three days after ACE, the blood pressure significantly increased in normal group, sham operated group and ACE group compared with non-ACE group(p<0.01). The blood pressure had no significant difference among the normal group, sham operated group and ACE group after ACE (p>0.05). The blood pressure post-ACE of the rats treated with nimodipine was decreased obviously.â‘¡The morbility of ischemic stroke after ACE was 0% in normal group, 0% in sham operated group, 0% in non-ACE group, 18.42% in ACE group, 10.81% in nimodipine group respectively. The morbility of ischemic stroke had no significant difference between ACE group and nimodipine group.â‘¢The serum concentration of sP-selectin, TM, ET-1 before ACE of normal group was lower than that of ACE group and nimodipine group. After ACE, the serum concentration of TM, ET-1 and NO increased in normal group. And the concentration of ET-1 and NO after ACE also significantly increased in the ACE group, which was significantly higher than that of nimodipine group.Conclusion:This study reveals that artificial cold exposure could increase the blood pressure and the morbility of ischemic stroke in carotid atherosclerotic rats. After ACE the endothelial functional disturbance was also aggravated. This effect of ACE on blood pressure and endothelial function might be attenuated by nimodipine.