Corpus callosum: interactive effects of infantile handling and testosterone in the rat.
Previous research found that the corpus callosum of male rats is larger than that of females; handling rats in infancy enhances this sex difference; and female rat pups, when handled in infancy and given 1 injection of testosterone propionate (TP) on Day 4 of life, will have callosa as large as those of males. In 2 experiments, male pups were castrated on Day 1 or received sham surgery; female pups were injected with TP on Day 4 or received an oil injection. Litters were handled or nonhandled. The previous finding that females, when handled and given TP in infancy, have a larger callosum was confirmed; however, a TP effect when administered to nonhandled females was not found. Because handling is known to cause a corticosterone release, these findings were interpreted as evidence of a developmental interaction between adrenal and gonadal hormones at the cortical level.
Department of Psychology University of Connecticut Storrs, 06269-4154.
V H
VH
Denenberg
R H
RH
Fitch
L M
LM
Schrott
P E
PE
Cowell
N S
NS
Waters
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology; D003337:Corpus Callosum / Q000502:physiology*; D005260:Female; D006234:Handling, Psychological; D008297:Male; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D012733:Sex Differentiation / Q000502:physiology*; D013739:Testosterone / Q000502:physiology*
D013739:Testosterone