Cryoanethesia on postnatal day 1, but not day 10, affects adult behavior and cortical morphology in rats.
Hypothermia was used to induce anesthesia in infant rats on postnatal days 1 or 10. In adulthood measures of spatial learning and activity were taken before the brains were harvested for measurement of cortical thickness and dendritic arborization in layer III pyramidal cells in parietal cortex. Cryoanethesia on day 1, but not day 10, produced a small, but statistically significant, impairment in learning a spatial navigation task as well as a reduction in cortical thickness and dendritic arborization. This study confirms that cryoanesthesia is not a benign treatment in newborn pups but appears to be without effect in older animals. It is important that all studies using cryoanesthesia have sham control animals exposed to the same degree of hypothermia.
Kolb
B
B
Department of Psychology and Neuroscience, University of Lethbridge, Lethbridge, Alberta, T1K 3M4 Canada. kolb@uleth.ca
Cioe
J
J
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001522:Behavior, Animal; D002540:Cerebral Cortex / Q000166:cytology / Q000254:growth & development* / Q000502:physiology*; D003712:Dendrites / Q000502:physiology; D007036:Hypothermia, Induced / Q000009:adverse effects*; D018782:Maze Learning; D009043:Motor Activity; D009929:Organ Size; D051381:Rats; D020318:Rats, Long-Evans