M. Baroncini, C. Allet, D. Leroy, J. Beauvillain, J. Francke et al., Morphological Evidence for Direct Interaction Between Gonadotrophin-Releasing Hormone Neurones and Astroglial Cells in the Human Hypothalamus, Journal of Neuroendocrinology, vol.34, issue.9, pp.691-702, 2007.
DOI : 10.1007/BF01474540

URL : https://hal.archives-ouvertes.fr/inserm-00363976

L. Barros, O. Porras, and C. Bittner, Why glucose transport in the brain matters for PET, Trends in Neurosciences, vol.28, issue.3, pp.117-119, 2005.
DOI : 10.1016/j.tins.2005.01.002

S. De-seranno, X. Anglemont-de-tassigny, C. Estrella, A. Loyens, S. Kasparov et al., Role of Estradiol in the Dynamic Control of Tanycyte Plasticity Mediated by Vascular Endothelial Cells in the Median Eminence, Endocrinology, vol.151, issue.4, 2010.
DOI : 10.1210/en.2009-0870

URL : https://hal.archives-ouvertes.fr/inserm-00487088

Q. Gao, . Mg, Y. Nie, Y. Rao, C. Choi et al., Anorectic estrogen mimics leptin's effect on the rewiring of melanocortin cells and Stat3 signaling in obese animals, Nature Medicine, vol.26, issue.1, pp.89-94, 2007.
DOI : 10.1038/nm1525

L. Garcia-segura, J. Chowen, M. Duenas, I. Torres-aleman, and F. Naftolin, Gonadal steroids as promoters of neuro-glial plasticity, Psychoneuroendocrinology, vol.19, issue.5-7, pp.445-453, 1994.
DOI : 10.1016/0306-4530(94)90031-0

G. Hatton, FUNCTION-RELATED PLASTICITY IN HYPOTHALAMUS, Annual Review of Neuroscience, vol.20, issue.1, pp.375-397, 1997.
DOI : 10.1146/annurev.neuro.20.1.375

D. Hemrika, E. Slaats, J. Kennedy, T. De-vries-robles-korsen, and J. Schoemaker, Pulsatile luteinizing hormone patterns in long term oral contraceptive users, J Clin Endocrinol Metab, vol.77, pp.420-426, 1993.

A. Herbison, Physiology of the Gonadotropin-Releasing Hormone Neuronal Network, Neill JD, pp.1415-1482, 2006.
DOI : 10.1016/B978-012515400-0/50033-6

J. Hotchkiss and E. Knobil, The menstrual cycle and its neuroendocrine control, Second Edition, 1994.

J. King and R. Letourneau, Luteinizing hormone-releasing hormone terminals in the median eminence of rats undergo dramatic changes after gonadectomy, as revealed by electron microscopic image analysis, Endocrinology, vol.134, pp.1340-1351, 1994.

L. Bihan and D. , Looking into the functional architecture of the brain with diffusion MRI, Nature Reviews Neuroscience, vol.4, issue.6, pp.469-480, 2003.
DOI : 10.1038/nrn1119

URL : https://hal.archives-ouvertes.fr/hal-00349696

L. Bihan and D. , The ???wet mind???: water and functional neuroimaging, Physics in Medicine and Biology, vol.52, issue.7, pp.57-90, 2007.
DOI : 10.1088/0031-9155/52/7/R02

URL : https://hal.archives-ouvertes.fr/hal-00349653

J. Liu and Y. Ss, Induction of midcycle gonadotropin surge by ovarian steroids in women: a critical evaluation, J Clin Endocrinol Metab, vol.57, pp.797-802, 1983.

L. Manganas, X. Zhang, Y. Li, R. Hazel, S. Smith et al., Magnetic Resonance Spectroscopy Identifies Neural Progenitor Cells in the Live Human Brain, Science, vol.318, issue.5852, pp.980-985, 2007.
DOI : 10.1126/science.1147851

A. Nehlig and J. Coles, Cellular pathways of energy metabolism in the brain: Is glucose used by neurons or astrocytes?, Glia, vol.6, issue.12, pp.1238-1250, 2007.
DOI : 10.1002/glia.20376

URL : https://hal.archives-ouvertes.fr/inserm-00381748

D. Norris, T. Niendorf, and D. Leibfritz, Healthy and infarcted brain tissues studied at short diffusion times: The origins of apparent restriction and the reduction in apparent diffusion coefficient, NMR in Biomedicine, vol.91, issue.7, pp.304-310, 1994.
DOI : 10.1002/nbm.1940070703

S. Ojeda, Y. Ma, B. Lee, and V. Prevot, Glia-to-neuron signaling and the neuroendocrine control of female puberty, Annals of Medicine, vol.298, issue.319, pp.197-223, 2000.
DOI : 10.1006/dbio.1996.0212

S. Oliet, R. Piet, and D. Poulain, Control of Glutamate Clearance and Synaptic Efficacy by Glial Coverage of Neurons, Science, vol.292, issue.5518, pp.923-926, 2001.
DOI : 10.1126/science.1059162

URL : https://hal.archives-ouvertes.fr/inserm-00000059

W. Ottowitz, D. Dougherty, A. Fischman, and J. Hall, -Glucose Positron Emission Tomography Demonstration of Estrogen Negative and Positive Feedback on Luteinizing Hormone Secretion in Women, The Journal of Clinical Endocrinology & Metabolism, vol.93, issue.8, pp.3208-3214, 2008.
DOI : 10.1210/jc.2008-0203

A. Panatier, D. Theodosis, J. Mothet, B. Touquet, L. Pollegioni et al., Glia-Derived d-Serine Controls NMDA Receptor Activity and Synaptic Memory, Cell, vol.125, issue.4, pp.775-784, 2006.
DOI : 10.1016/j.cell.2006.02.051

URL : https://hal.archives-ouvertes.fr/inserm-00078312

R. Piet, L. Vargova, E. Sykova, D. Poulain, and S. Oliet, Physiological contribution of the astrocytic environment of neurons to intersynaptic crosstalk, Proceedings of the National Academy of Sciences, vol.101, issue.7, pp.2151-2155, 2004.
DOI : 10.1073/pnas.0308408100

URL : https://hal.archives-ouvertes.fr/inserm-00000063

V. Prevot, B. Dehouck, P. Poulain, J. Beauvillain, V. Buee-scherrer et al., Neuronal???glial???endothelial interactions and cell plasticity in the postnatal hypothalamus: Implications for the neuroendocrine control of reproduction, Psychoneuroendocrinology, vol.32, pp.46-51, 2007.
DOI : 10.1016/j.psyneuen.2007.03.018

V. Prevot, D. Croix, S. Bouret, S. Dutoit, G. Tramu et al., Definitive evidence for the existence of morphological plasticity in the external zone of the median eminence during the rat estrous cycle: implication of neuro-glio-endothelial interactions in gonadotropin-releasing hormone release, Neuroscience, vol.94, issue.3, pp.809-819, 1999.
DOI : 10.1016/S0306-4522(99)00383-8

B. Ross and S. Bluml, Magnetic resonance spectroscopy of the human brain, The Anatomical Record, vol.8, issue.2, pp.54-84, 2001.
DOI : 10.1002/ar.1058

R. Simerly, Wired on hormones: endocrine regulation of hypothalamic development, Current Opinion in Neurobiology, vol.15, issue.1, pp.81-85, 2005.
DOI : 10.1016/j.conb.2005.01.013

A. Taylor, H. Whitney, J. Hall, K. Martin, W. Crowley et al., Midcycle levels of sex steroids are sufficient to recreate the follicle-stimulating hormone but not the luteinizing hormone midcycle surge: evidence for the contribution of other ovarian factors to the surge in normal women., The Journal of Clinical Endocrinology & Metabolism, vol.80, issue.5, pp.1541-1547, 1995.
DOI : 10.1210/jcem.80.5.7744998

D. Theodosis, D. Poulain, and S. Oliet, Activity-Dependent Structural and Functional Plasticity of Astrocyte-Neuron Interactions, Physiological Reviews, vol.88, issue.3, pp.983-1008, 2008.
DOI : 10.1152/physrev.00036.2007

J. Urenjak, S. Williams, D. Gadian, and M. Noble, Proton nuclear magnetic resonance spectroscopy unambiguously identifies different neural cell types, J Neurosci, vol.13, pp.981-989, 1993.

L. Vanhamme, A. Van-den-boogaart, and S. Van-huffel, Improved Method for Accurate and Efficient Quantification of MRS Data with Use of Prior Knowledge, Journal of Magnetic Resonance, vol.129, issue.1, pp.35-43, 1997.
DOI : 10.1006/jmre.1997.1244

J. Witkin, M. Ferin, S. Popilskis, and A. Silverman, Effects of Gonadal Steroids on the Ultrastructure of GnRH Neurons in the Rhesus Monkey: Synaptic Input and Glial Apposition*, Endocrinology, vol.129, issue.2, pp.1083-1092, 1991.
DOI : 10.1210/endo-129-2-1083

T. Yamamura, K. Hirunagi, S. Ebihara, and T. Yoshimura, Seasonal Morphological Changes in the Neuro-Glial Interaction between Gonadotropin-Releasing Hormone Nerve Terminals and Glial Endfeet in Japanese Quail, Endocrinology, vol.145, issue.9, pp.4264-4267, 2004.
DOI : 10.1210/en.2004-0366

/. Cho and . Naa, and d13 of their oral contraception cycle (n = 10), and in men (n = 10) in the hypothalamus and thalamus, respectively. P values were obtained from Student paired t-tests and ANOVA for d-2 vs