| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Division of Neurobiology, Department of Cell and Molecular Biology
3 Neuroscience Program, Tulane University, New Orleans, LA 70118, USA
2 Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
Exogenous cannabinoids have been shown to significantly alter neuroendocrine output, presaging the emergence of endogenous cannabinoids as important signalling molecules in the neuroendocrine control of homeostatic and reproductive functions, including the stress response, energy metabolism and gonadal regulation. We showed recently that magnocellular and parvocellular neuroendocrine cells of the hypothalamic paraventricular nucleus and supraoptic nucleus (SON) respond to glucocorticoids by releasing endocannabinoids as retrograde messengers to modulate the synaptic release of glutamate. Here we show directly for the first time that both of the main endocannabinoids, anandamide (AEA) and 2-arachidonoyl glycerol (2-AG), are released in an activity-dependent fashion from the soma/dendrites of SON magnocellular neurones and suppress synaptic glutamate release and postsynaptic spiking. Cannabinoid reuptake blockade increases activity-dependent endocannabinoid levels in the region of the SON, and results in the inhibition of synaptically driven spiking activity in magnocellular neurones. Together, these findings demonstrate an activity-dependent release of AEA and 2-AG that leads to the suppression of glutamate release and that is capable of shaping spiking activity in magnocellular neurones. This activity-dependent regulation of excitatory synaptic input by endocannabinoids may play a role in determining spiking patterns characteristic of magnocellular neurones under stimulated conditions.
(Received 25 August 2005;
accepted after revision 14 October 2005;
first published online 20 October 2005)
Corresponding author J. G. Tasker: Department of Cell and Molecular Biology, 2000 Percival Stern Hall, Tulane University, New Orleans, LA 70118-5698, USA. Email: tasker{at}tulane.edu
This article has been cited by other articles:
|
|
 |
|
  A.H. Taylor, C. Ang, S.C. Bell, and J.C. Konje The role of the endocannabinoid system in gametogenesis, implantation and early pregnancy Hum. Reprod. Update, September 1, 2007; 13(5): 501 - 513. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. J. Denver Endocannabinoids Link Rapid, Membrane-Mediated Corticosteroid Actions to Behavior Endocrinology, February 1, 2007; 148(2): 490 - 492. [Full Text] [PDF]
|
|
|
|
|
|
J. G. Tasker, S. Di, and R. Malcher-Lopes Rapid Glucocorticoid Signaling via Membrane-Associated Receptors Endocrinology, December 1, 2006; 147(12): 5549 - 5556. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Pacher, S. Batkai, and G. Kunos The Endocannabinoid System as an Emerging Target of Pharmacotherapy Pharmacol. Rev., September 1, 2006; 58(3): 389 - 462. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. E. Armstrong and G. I. Hatton The puzzle of pulsatile oxytocin secretion during lactation: some new pieces Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2006; 291(1): R26 - R28. [Full Text] [PDF]
|
|
|
|
 |
|
 R. Malcher-Lopes, S. Di, V. S. Marcheselli, F.-J. Weng, C. T. Stuart, N. G. Bazan, and J. G. Tasker Opposing crosstalk between leptin and glucocorticoids rapidly modulates synaptic excitation via endocannabinoid release. J. Neurosci., June 14, 2006; 26(24): 6643 - 6650. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
