Adrenal steroids regulate postnatal development of the rat dentate gyrus: I. Effects of glucocorticoids on cell death
- 15 November 1991
- journal article
- research article
- Published by Wiley in Journal of Comparative Neurology
- Vol. 313 (3), 479-485
- https://doi.org/10.1002/cne.903130308
Abstract
The rat dentate gyrus undergoes a period of naturally occurring cell death during the first postnatal week. In the adult rat, removal of circulating adrenal steroids by adrenalectomy is followed by massive death in the granule cell layer, thus raising the possibility that developmental cell death results from low levels of these hormones. Interestingly, the first two postnatal weeks of life in the rat, termed the stress hyporesponsive period, are characterized by very low levels of adrenal steroids. In order to determine whether low levels of adrenal steroids enable developmental cell death to occur in the dentate gyrus, we examined the density of pyknotic and healthy cells in the dentate gyrus of rat pups which received one of the following treatments: (1) injections of the endogenous rat glucocorticoid corticosterone during the first postnatal week, or (2) adrenalectomy at the time when glucocorticoid levels normally rise. Quantitative analysis of the density of pyknotic cells in the granule cell layers revealed significant decreases with corticosterone treatment by the end of the first postnatal week. In these same brains, treatment with corticosterone resulted in a substantial increase in the density of pyknotic cells in the hilus. Adrenalectomy resulted in a significant increase in the density of pyknotic cells in the granule cell layer as well as in the hilus. Despite the dramatic alterations in the density of pyknotic cells with both increases and decreases in glucocorticoid levels, the density of healthy cells remained the same. These observations suggest that glucocorticoids regulate several processes, possibly including neurogenesis and migration, in addition to cell death.Keywords
This publication has 22 references indexed in Scilit:
- Ontogeny of mineralocorticoid (type 1) receptors in brain and pituitary: an in vivo autoradiographical studyDevelopmental Brain Research, 1990
- Ontogeny of the Type 2 glucocorticoid receptor in discrete rat brain regions: an immunocytochemical studyDevelopmental Brain Research, 1988
- Stimulation of the receptor has a trophic effect on differentiating cerebellar granule cellsNeuroscience Letters, 1988
- Three‐dimensional structure of astrocytes in the rat dentate gyrusJournal of Comparative Neurology, 1986
- Maturation of the adrenocortical stress response: Neuroendocrine control mechanisms and the stress hyporesponsive periodBrain Research Reviews, 1986
- Neuronal death in the development of the vertebrate nervous systemTrends in Neurosciences, 1985
- Regressive Events in NeurogenesisScience, 1984
- Cell death in the mammalian visual system during normal development: I. Retinal ganglion cellsJournal of Comparative Neurology, 1982
- Development of the hippocampal region in the rat I. Neurogenesis examined with 3H‐thymidine autoradiographyJournal of Comparative Neurology, 1980
- An autoradiographic study of the time of origin and the pattern of granule cell migration in the dentate gyrus of the ratJournal of Comparative Neurology, 1975