The effect of adrenalectomy and corticosterone on homotypic collateral sprouting of serotonergic fibers in hippocampus.
Lesioning of serotonergic (5-HT) fibers using 5,7-dihydroxytryptamine (5,7-DHT) in one of the two median raphe-hippocampal pathways induced homotypic sprouting from the other. We have utilized this model with the horseradish peroxidase (HRP) tracing technique to test the effects of an adrenal corticosteroid-corticosterone on homotypic sprouting in female adult rats. Removal of the adrenal glands does not interfere with the 5,7-DHT destruction of 5-HT fibers observed at 3 days. However, the animals without circulating adrenal steroids do not show the increase of the HRP-labeled cells normally seen 21 days after the 5,7-DHT lesions. Furthermore, s.c. implantation of corticosterone pellets was able to completely restore homotypic sprouting of 5-HT fibers in the hippocampus.
D015116:5,7-Dihydroxytryptamine / Q000494:pharmacology; D000305:Adrenal Cortex Hormones / Q000502:physiology; D000315:Adrenalectomy; D000818:Animals; D003345:Corticosterone / Q000494:pharmacology*; D005260:Female; D006624:Hippocampus / Q000187:drug effects*; D009473:Neuronal Plasticity / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000502:physiology*
D000305:Adrenal Cortex Hormones; D015116:5,7-Dihydroxytryptamine; D012701:Serotonin; D003345:Corticosterone