Endothelin-1-Induced Focal Cerebral Ischemia in the Growth Hormone/IGF-1 Deficient Lewis Dwarf Rat

This study was designed to assess whether GH/IGF-1-deficiency influences the outcome of cerebral ischemia. We found that endothelin-1-induced middle cerebral artery occlusion resulted in a modest but nonsignificant decrease in cerebral infarct size in GH/IGF-1 deficient dw/dw rats compared with control heterozygous littermates and dw/dw rats with early-life GH treatment. Expression of endothelin receptors and endothelin-1-induced constriction of the middle cerebral arteries were similar in the three experimental groups. Interestingly, dw/dw rats exhibited reduced brain edema and less astrocytic infiltration compared with their heterozygous littermates and this effect was reversed by GH-treatment. Because reactive astrocytes are critical for the regulation of poststroke inflammatory processes, maintenance of the blood–brain barrier and neural repair, further studies are warranted to determine the long-term functional consequences of decreased astrocytic activation in GH/IGF-1 deficient animals after cerebral ischemia.

Source: Journals of Gerontology Series A: Biological Sciences and Medical Sciences - October 9, 2014 Category: Geriatrics Authors: Yan, H., Mitschelen, M., Toth, P., Ashpole, N. M., Farley, J. A., Hodges, E. L., Warrington, J. P., Han, S., Fung, K.-M., Csiszar, A., Ungvari, Z., Sonntag, W. E. Tags: Original Article Source Type: research