Cargando…
Estrus cyclicity of spinogenesis: underlying mechanisms
Hippocampal spine density varies with the estrus cycle. The cyclic change in estradiol levels in serum was hypothesized to underlie this phenomenon, since treatment of ovariectomized animals with estradiol induced an increase in spine density in hippocampal dendrites of rats, as compared to ovariect...
Autores principales: | , , , , |
---|---|
Formato: | Texto |
Lenguaje: | English |
Publicado: |
Springer Vienna
2009
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3085745/ https://www.ncbi.nlm.nih.gov/pubmed/19730783 http://dx.doi.org/10.1007/s00702-009-0294-x |
_version_ | 1782202650398294016 |
---|---|
author | Prange-Kiel, Janine Fester, Lars Zhou, Lepu Jarry, Hubertus Rune, Gabriele M. |
author_facet | Prange-Kiel, Janine Fester, Lars Zhou, Lepu Jarry, Hubertus Rune, Gabriele M. |
author_sort | Prange-Kiel, Janine |
collection | PubMed |
description | Hippocampal spine density varies with the estrus cycle. The cyclic change in estradiol levels in serum was hypothesized to underlie this phenomenon, since treatment of ovariectomized animals with estradiol induced an increase in spine density in hippocampal dendrites of rats, as compared to ovariectomized controls. In contrast, application of estradiol to hippocampal slice cultures did not promote spinogenesis. In addressing this discrepancy, we found that hippocampal neurons themselves are capable of synthesizing estradiol de novo. Estradiol synthesis can be suppressed by aromatase inhibitors and by knock-down of Steroid Acute Regulatory Protein (StAR) and enhanced by substrates of steroidogenesis. Expression of estrogen receptors (ERs) and synaptic proteins, synaptogenesis, and long-term potentiation (LTP) correlated positively with aromatase activity in hippocampal cultures without any difference between genders. All effects due to inhibition of aromatase activity were rescued by application of estradiol to the cultures. Most importantly, gonadotropin-releasing hormone (GnRH) increased estradiol synthesis dose-dependently via an aromatase-mediated mechanism and consistently increased spine synapse density and spinophilin expression. As a consequence, our data suggest that cyclic fluctuations in spine synapse density result from pulsative release of GnRH from the hypothalamus and its effect on hippocampal estradiol synthesis, rather than from varying levels of serum estradiol. This hypothesis is further supported by higher GnRH receptor (GnRH-R) density in the hippocampus than in the cortex and hypothalamus and the specificity of estrus cyclicity of spinogenesis in the hippocampus, as compared to the cortex. |
format | Text |
id | pubmed-3085745 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2009 |
publisher | Springer Vienna |
record_format | MEDLINE/PubMed |
spelling | pubmed-30857452011-06-06 Estrus cyclicity of spinogenesis: underlying mechanisms Prange-Kiel, Janine Fester, Lars Zhou, Lepu Jarry, Hubertus Rune, Gabriele M. J Neural Transm Basic Neurosciences, Genetics and Immunology - Original Article Hippocampal spine density varies with the estrus cycle. The cyclic change in estradiol levels in serum was hypothesized to underlie this phenomenon, since treatment of ovariectomized animals with estradiol induced an increase in spine density in hippocampal dendrites of rats, as compared to ovariectomized controls. In contrast, application of estradiol to hippocampal slice cultures did not promote spinogenesis. In addressing this discrepancy, we found that hippocampal neurons themselves are capable of synthesizing estradiol de novo. Estradiol synthesis can be suppressed by aromatase inhibitors and by knock-down of Steroid Acute Regulatory Protein (StAR) and enhanced by substrates of steroidogenesis. Expression of estrogen receptors (ERs) and synaptic proteins, synaptogenesis, and long-term potentiation (LTP) correlated positively with aromatase activity in hippocampal cultures without any difference between genders. All effects due to inhibition of aromatase activity were rescued by application of estradiol to the cultures. Most importantly, gonadotropin-releasing hormone (GnRH) increased estradiol synthesis dose-dependently via an aromatase-mediated mechanism and consistently increased spine synapse density and spinophilin expression. As a consequence, our data suggest that cyclic fluctuations in spine synapse density result from pulsative release of GnRH from the hypothalamus and its effect on hippocampal estradiol synthesis, rather than from varying levels of serum estradiol. This hypothesis is further supported by higher GnRH receptor (GnRH-R) density in the hippocampus than in the cortex and hypothalamus and the specificity of estrus cyclicity of spinogenesis in the hippocampus, as compared to the cortex. Springer Vienna 2009-09-04 2009-11 /pmc/articles/PMC3085745/ /pubmed/19730783 http://dx.doi.org/10.1007/s00702-009-0294-x Text en © Springer-Verlag 2009 |
spellingShingle | Basic Neurosciences, Genetics and Immunology - Original Article Prange-Kiel, Janine Fester, Lars Zhou, Lepu Jarry, Hubertus Rune, Gabriele M. Estrus cyclicity of spinogenesis: underlying mechanisms |
title | Estrus cyclicity of spinogenesis: underlying mechanisms |
title_full | Estrus cyclicity of spinogenesis: underlying mechanisms |
title_fullStr | Estrus cyclicity of spinogenesis: underlying mechanisms |
title_full_unstemmed | Estrus cyclicity of spinogenesis: underlying mechanisms |
title_short | Estrus cyclicity of spinogenesis: underlying mechanisms |
title_sort | estrus cyclicity of spinogenesis: underlying mechanisms |
topic | Basic Neurosciences, Genetics and Immunology - Original Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3085745/ https://www.ncbi.nlm.nih.gov/pubmed/19730783 http://dx.doi.org/10.1007/s00702-009-0294-x |
work_keys_str_mv | AT prangekieljanine estruscyclicityofspinogenesisunderlyingmechanisms AT festerlars estruscyclicityofspinogenesisunderlyingmechanisms AT zhoulepu estruscyclicityofspinogenesisunderlyingmechanisms AT jarryhubertus estruscyclicityofspinogenesisunderlyingmechanisms AT runegabrielem estruscyclicityofspinogenesisunderlyingmechanisms |