| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
The Journal of Neurophysiology Vol. 84 No. 3 September 2000, pp. 1464-1474
Copyright ©2000 by the American Physiological Society
U.159 Institut National de la Santé et de la Recherche Medicale Centre Paul Broca, 75014 Paris, France
Lanneau, Christophe,
Stéphane Peineau,
Florence Petit,
Jacques Epelbaum, and
Robert Gardette.
Somatostatin Modulation of Excitatory Synaptic Transmission
Between Periventricular and Arcuate Hypothalamic Nuclei In
Vitro. J. Neurophysiol. 84: 1464-1474, 2000. Hypophysiotropic somatostatin (SRIF) and growth
hormone-releasing hormone (GHRH) neurons are primarily involved in the
neurohormonal control of growth hormone (GH) secretion. They are
located in periventricular (PEV) and arcuate (ARC) hypothalamic nuclei,
respectively, but their connectivity is not well defined. To better
understand the neuronal network involved in the control of GH
secretion, connections from PEV to ARC neurons were reconstructed in
vitro and neuronal phenotypes assessed by single-cell multiplex RT-PCR. Of 814 stimulated PEV neurons, monosynaptic responses were detected in
only 45 ARC neurons. Monosynaptic excitatory currents were detected in
29 ARC neurons and inhibitory currents in 16, indicating a 2/1 ratio
for excitatory versus inhibitory connections. Galanin (GAL), NPY,
pro-opiomelanocortin (POMC), and SRIF mRNAs were detected in
neurons from both nuclei but GHRH mRNA almost exclusively in ARC. Among
the five SRIF receptors, only sst1 and sst2 were expressed, in 94% of
ARC and 59% of PEV neurons, respectively. Of 128 theoritical combinations between neuropeptides and sst receptors, only 22 were
represented in PEV and 25 in ARC. For PEV neurons, neuropeptide phenotypes did not influence excitatory connections. However, the
occurrence of presynaptic sst receptors on GAL and SRIF PEV neurons
significantly increased their probability of connection to ARC neurons.
GHRH ARC neurons expressing sst2, but not sst1, receptors were always
connected with PEV neurons. Physiological responses to sst1 (CH-275) or
sst2 (Octreotide) agonists were always correlated with the detection of
respective sst mRNAs. In conclusion, 1) SRIF-modulated
excitatory transmission develops in vitro from PEV to ARC neurons,
2) ARC GHRH neurons bearing sst2 receptors appears directly
controlled by fast glutamatergic transmission from PEV neurons
simultaneously expressing one to four neuropeptides, 3) GHRH
neurons bearing sst1 receptors lack this control, and 4)
these results suggest that fast excitatory neurotransmission and
neuropeptide modulation can derive from a small subset of PEV
hypothalamic neurons targeted at ARC neuronal subpopulations.
This article has been cited by other articles:
|
|
 |
|
  Z. Peterfi, G. B. Makara, F. Obal Jr., and J. M. Krueger The anterolateral projections of the medial basal hypothalamus affect sleep Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2009; 296(4): R1228 - R1238. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. S. Farhy, C. Y. Bowers, and J. D. Veldhuis Model-projected mechanistic bases for sex differences in growth hormone regulation in humans Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2007; 292(4): R1577 - R1593. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Mano-Otagiri, T. Nemoto, A. Sekino, N. Yamauchi, Y. Shuto, H. Sugihara, S. Oikawa, and T. Shibasaki Growth Hormone-Releasing Hormone (GHRH) Neurons in the Arcuate Nucleus (Arc) of the Hypothalamus Are Decreased in Transgenic Rats Whose Expression of Ghrelin Receptor Is Attenuated: Evidence that Ghrelin Receptor Is Involved in the Up-Regulation of GHRH Expression in the Arc Endocrinology, September 1, 2006; 147(9): 4093 - 4103. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Momiyama and L. Zaborszky Somatostatin Presynaptically Inhibits Both GABA and Glutamate Release Onto Rat Basal Forebrain Cholinergic Neurons J Neurophysiol, August 1, 2006; 96(2): 686 - 694. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. S. Farhy and J. D. Veldhuis Deterministic construct of amplifying actions of ghrelin on pulsatile growth hormone secretion Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2005; 288(6): R1649 - R1663. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Balthasar, P.-F. Mery, C. B. Magoulas, K. E. Mathers, A. Martin, P. Mollard, and I. C. A. F. Robinson Growth Hormone-Releasing Hormone (GHRH) Neurons in GHRH-Enhanced Green Fluorescent Protein Transgenic Mice: A Ventral Hypothalamic Network Endocrinology, June 1, 2003; 144(6): 2728 - 2740. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Peineau, B. Potier, F. Petit, P. Dournaud, J. Epelbaum, and R. Gardette AMPA-sst2 somatostatin receptor interaction in rat hypothalamus requires activation of NMDA and/or metabotropic glutamate receptors and depends on intracellular calcium J. Physiol., January 1, 2003; 546(1): 101 - 117. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Obal Jr., J. Alt, P. Taishi, J. Gardi, and J. M. Krueger Sleep in mice with nonfunctional growth hormone-releasing hormone receptors Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2003; 284(1): R131 - R139. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
