What is the Optimal Duration of Middle-Cerebral Artery Occlusion Consistently Resulting in Isolated Cortical Selective Neuronal Loss in the Spontaneously @entity101 XXXX ?

@entity101 @entity2806 @entity39 @entity2500 @entity2141 @entity854 @entity1188 @entity40 @entity35
INTRODUCTION AND OBJECTIVES: Selective neuronal loss (SNL) in the reperfused penumbra may impact clinical recovery and is thus important to investigate. Brief proximal @entity2500 ( @entity2500 ) results in predominantly striatal SNL, yet cortical damage is more relevant given its behavioral implications and that thrombolytic therapy mainly rescues the cortex. Distal temporary @entity2500 (tMCAo) does target the cortex, but the optimal occlusion duration that results in isolated SNL has not been determined. In the present study, we assessed different distal tMCAo durations looking for consistently pure SNL. METHODS: Microclip distal tMCAo (md-tMCAo) was performed in ~6-month old male spontaneously @entity101 @entity35 (SHRs). We previously reported that 45   min md-tMCAo in SHRs results in pan- @entity39 in the majority of subjects. Accordingly, three @entity2500 were investigated here in decremental succession, namely 30, 22, and 15   min (n   =   3, 3, and 7 subjects, respectively). Recanalization was confirmed by MR angiography just prior to brain collection at 28   days and T2-weighted MRI was obtained for characterization of @entity2806 . @entity2141 , OX42, and @entity40 immunohistochemistry appraised changes in neurons, microglia, and astrocytes, respectively. @entity2806 were categorized into three main types: (1) pan- @entity39 ; (2) partial @entity1188 ; and (3) SNL. RESULTS: Pan- @entity39 or partial @entity1188 was present in all 30   min and 22   min subjects, but not in the 15   min group (p   <   0.001), in which isolated cortical SNL was consistently present. MRI revealed @entity854 in all @entity35 with pan- @entity39 or partial @entity1188 , but no change in any 15   min subject. CONCLUSION: We found that 15   min distal @entity2500 consistently resulted in pure cortical SNL, whereas durations equal or longer than 22   min consistently resulted in @entity1188 . This model may be of use to study the pathophysiology of cortical SNL and its prevention by appropriate interventions.
