Neuroprotective effect of mivazerol, an alpha 2-agonist, after transient forebrain ischemia in rats.
BACKGROUND
We examined whether mivazerol, an alpha2-agonist, had neuroprotective effects after transient forebrain ischemia in rats.


METHODS
Male Sprague-Dawley rats, anesthetized with halothane, were assigned to one of four groups (n=10 each): control (C, normal saline) and mivazerol 10 microg/kg (M10), 20 microg/kg (M20) and 40 microg/kg (M40) groups. Thirty minutes after drug administration, forebrain ischemia was induced with hemorrhagic hypotension and bilateral carotid artery occlusion for 10 min, and then the brain was reperfused. The neurologic outcome was evaluated 24 h, 48 h and 7 days after ischemia, followed by histologic evaluation.


RESULTS
The survival rate during 7 days was significantly lower in group M40 than in groups M10 and M20 (P<0.05). The neurologic outcome was significantly better in groups M10 and M20 than in group M40 7 days after ischemia (P<0.05). The number of intact neurons in hippocampal CA1 was significantly greater in group M20 than in the other groups (P<0.05). Neuronal injury in the neocortex was significantly less in group M20 than in groups C and M40 (P<0.05).


CONCLUSIONS
Our results suggest that mivazerol, up to 20 microg/kg, provides neuroprotective effects, whereas 40 microg/kg may exaggerate neuronal injury after transient forebrain ischemia in rats.
Kimura
T
T
Department of Anesthesia and Intensive Care Medicine, Akita University School of Medicine, Akita, Japan. kimtetsu@doc.med.akita-u.ac.jp
Sato
M
M
Nishikawa
T
T
Tanaka
M
M
Tobe
Y
Y
Masaki
Y
Y
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000818:Animals; D001784:Blood Gas Analysis; D001786:Blood Glucose / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D004195:Disease Models, Animal; D006339:Heart Rate / Q000187:drug effects; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007093:Imidazoles / Q000494:pharmacology*; D002546:Ischemic Attack, Transient / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology; D008297:Male; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015996:Survival Rate; D013997:Time Factors
D000316:Adrenergic alpha-Agonists; D001786:Blood Glucose; D007093:Imidazoles; D018696:Neuroprotective Agents; C087969:mivazerol