Functional integration of fetal cortical grafts into the afferent pathway of the rat somatosensory cortex (SmI).
The somatosensory area of fetal (E15-16) Sprague-Dawley rat neocortex was implanted into the barrel receptor area of adult first somatosensory cortex (SmI) to determine if it could be integrated into the host vibrissa-cortical pathway. Functional integration was tested 3-6 months later using the 2-deoxyglucose [44,45] (2-dg) method for estimation of glucose utilization. A variety of control grafts (cerebellum in SmI cortex, neocortex outside the host SmI cortex and appropriately placed neocortex in non-stimulated hosts) all had uniform 2-dg uptake (70 +/- 10 mumol/100 g/min) throughout each graft which averaged 42% less than non-stimulated host SmI cortex (121 +/- 6 mumol/100 g/min; p less than 0.001) but was 3-fold greater than white matter (24.8 +/- 3.1 mumol/100 g/min; p less than 0.001). In appropriately placed neocortical grafts, vibrissal stimulation produced 125% greater average 2-dg uptake (157 +/- 19 mumol/100 g/min) than control grafts (p less than 0.01). Such appropriately placed and stimulated neocortical grafts also contained focal areas of increased 2-dg uptake which were 43% greater than average graft uptake. These data suggest that fetal neocortical grafts were functionally integrated into the physiologically relevant afferent pathways of adult host brains.
Neurology Service, Veterans Administration Medical Center, East Orange, NJ 07019.
B E
BE
Levin
A
A
Dunn-Meynell
A F
AF
Sved
D000344:Afferent Pathways / Q000166:cytology / Q000502:physiology*; D000818:Animals; D001921:Brain / Q000378:metabolism; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism / Q000637:transplantation*; D003847:Deoxyglucose / Q000378:metabolism; D005333:Fetus; D008297:Male; D009928:Organ Specificity; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D013003:Somatosensory Cortex / Q000166:cytology / Q000502:physiology*
D003847:Deoxyglucose