 |
The Journal of Neuroscience, March 2, 2005, 25(9):2285-2294; doi:10.1523/JNEUROSCI.3877-04.2005
Previous Article | Next Article 
Development/Plasticity/Repair
Neurosteroid-Induced Plasticity of Immature Synapses via Retrograde Modulation of Presynaptic NMDA Receptors
Manuel Mameli,
Mario Carta,
L. Donald Partridge, and
C. Fernando Valenzuela
Department of Neurosciences, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 87131
Neurosteroids are produced de novo in neuronal and glial cells, which begin to express steroidogenic enzymes early in development. Studies suggest that neurosteroids may play important roles in neuronal circuit maturation via autocrine and/or paracrine actions. However, the mechanism of action of these agents is not fully understood. We report here that the excitatory neurosteroid pregnenolone sulfate induces a long-lasting strengthening of AMPA receptor-mediated synaptic transmission in rat hippocampal neurons during a restricted developmental period. Using the acute hippocampal slice preparation and patch-clamp electrophysiological techniques, we found that pregnenolone sulfate increases the frequency of AMPA-mediated miniature excitatory postsynaptic currents in CA1 pyramidal neurons. This effect could not be observed in slices from rats older than postnatal day 5. The mechanism of action of pregnenolone sulfate involved a short-term increase in the probability of glutamate release, and this effect is likely mediated by presynaptic NMDA receptors containing the NR2D subunit, which is transiently expressed in the hippocampus. The increase in glutamate release triggered a long-term enhancement of AMPA receptor function that requires activation of postsynaptic NMDA receptors containing NR2B subunits. Importantly, synaptic strengthening could also be triggered by postsynaptic neuron depolarization, and an anti-pregnenolone sulfate antibody scavenger blocked this effect. This finding indicates that a pregnenolone sulfate-like neurosteroid is a previously unrecognized retrograde messenger that is released in an activity-dependent manner during development.
Key words: steroid; neurotransmitter; release; channel; presynaptic; plasticity
Received Sep 17, 2004;
revised January 18, 2005;
accepted January 20, 2005.
This article has been cited by other articles:

|
 |

|
 |
 
P. Inquimbert, J.-L. Rodeau, and R. Schlichter
Regional Differences in the Decay Kinetics of GABAA Receptor-Mediated Miniature IPSCs in the Dorsal Horn of the Rat Spinal Cord Are Determined by Mitochondrial Transport of Cholesterol
J. Neurosci.,
March 26, 2008;
28(13):
3427 - 3437.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. J. Brasier and D. E. Feldman
Synapse-Specific Expression of Functional Presynaptic NMDA Receptors in Rat Somatosensory Cortex
J. Neurosci.,
February 27, 2008;
28(9):
2199 - 2211.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. Corlew, Y. Wang, H. Ghermazien, A. Erisir, and B. D. Philpot
Developmental Switch in the Contribution of Presynaptic and Postsynaptic NMDA Receptors to Long-Term Depression
J. Neurosci.,
September 12, 2007;
27(37):
9835 - 9845.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Chen, Y. Miyamoto, K. Furuya, N. Mori, and M. Sokabe
PREGS Induces LTP in the Hippocampal Dentate Gyrus of Adult Rats Via the Tyrosine Phosphorylation International Cooperative Research CREB Signaling
J Neurophysiol,
September 1, 2007;
98(3):
1538 - 1548.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Makani and M. Chesler
Endogenous Alkaline Transients Boost Postsynaptic NMDA Receptor Responses in Hippocampal CA1 Pyramidal Neurons
J. Neurosci.,
July 11, 2007;
27(28):
7438 - 7446.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. R. B. Schiess, C. S. Scullin, and L. D. Partridge
Neurosteroid-induced enhancement of short-term facilitation involves a component downstream from presynaptic calcium in hippocampal slices
J. Physiol.,
November 1, 2006;
576(3):
833 - 847.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. J. Ebner, D. I. Corol, H. Havlikova, J. W. Honour, and J. P. Fry
Identification of Neuroactive Steroids and Their Precursors and Metabolites in Adult Male Rat Brain
Endocrinology,
January 1, 2006;
147(1):
179 - 190.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Chen and M. Sokabe
Presynaptic Modulation of Synaptic Transmission by Pregnenolone Sulfate as Studied by Optical Recordings
J Neurophysiol,
December 1, 2005;
94(6):
4131 - 4144.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Mameli, P. A. Zamudio, M. Carta, and C. F. Valenzuela
Developmentally Regulated Actions of Alcohol on Hippocampal Glutamatergic Transmission
J. Neurosci.,
August 31, 2005;
25(35):
8027 - 8036.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|