PMID- 18480251
OWN - NLM
STAT- MEDLINE
DCOM- 20080624
LR  - 20211020
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 105
IP  - 20
DP  - 2008 May 20
TI  - Estradiol modulation of phenylephrine-induced excitatory responses in 
      ventromedial hypothalamic neurons of female rats.
PG  - 7333-8
LID - 10.1073/pnas.0802760105 [doi]
AB  - Estrogens act within the ventromedial nucleus of the hypothalamus (VMN) to 
      facilitate lordosis behavior. Estradiol treatment in vivo induces 
      alpha(1b)-adrenoreceptor mRNA and increases the density of 
      alpha(1B)-adrenoreceptor binding in the hypothalamus. Activation of hypothalamic 
      alpha(1)-adrenoceptors also facilitates estrogen-dependent lordosis. To 
      investigate the cellular mechanisms of adrenergic effects on VMN neurons, 
      whole-cell patch-clamp recordings were carried out on hypothalamic slices from 
      control and estradiol-treated female rats. In control slices, bath application of 
      the alpha(1)-agonist phenylephrine (PHE; 10 microM) depolarized 10 of 25 neurons 
      (40%), hyperpolarized three neurons (12%), and had no effect on 12 neurons (48%). 
      The depolarization was associated with decreased membrane conductance, and this 
      current had a reversal potential close to the K(+) equilibrium potential. The 
      alpha(1b)-receptor antagonist chloroethylclonidine (10 microM) blocked the 
      depolarization produced by PHE in all cells. From estradiol-treated rats, 
      significantly more neurons in slices depolarized (71%) and fewer neurons showed 
      no response (17%) to PHE. PHE-induced depolarizations were significantly 
      attenuated with 4-aminopyridine (5 mM) but unaffected by tetraethylammonium 
      chloride (20 mM) or blockers of Na(+) and Ca(2+) channels. These data indicate 
      that alpha(1)-adrenoceptors depolarize VMN neurons by reducing membrane 
      conductance for K(+). Estradiol amplifies alpha(1b)-adrenergic signaling by 
      increasing the proportion of VMN neurons that respond to stimulation of 
      alpha(1b)-adrenergic receptors, which is expected in turn to promote lordosis.
FAU - Lee, Anna W
AU  - Lee AW
AD  - Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY 
      10065, USA. leeaw@rockefeller.edu
FAU - Kyrozis, Andreas
AU  - Kyrozis A
FAU - Chevaleyre, Vivien
AU  - Chevaleyre V
FAU - Kow, Lee-Ming
AU  - Kow LM
FAU - Devidze, Nino
AU  - Devidze N
FAU - Zhang, Qiuyu
AU  - Zhang Q
FAU - Etgen, Anne M
AU  - Etgen AM
FAU - Pfaff, Donald W
AU  - Pfaff DW
LA  - eng
GR  - HD05751/HD/NICHD NIH HHS/United States
GR  - R37 HD005751/HD/NICHD NIH HHS/United States
GR  - MH38273/MH/NIMH NIH HHS/United States
GR  - R37 MH041414/MH/NIMH NIH HHS/United States
GR  - R01 MH038273/MH/NIMH NIH HHS/United States
GR  - R37 MH41414/MH/NIMH NIH HHS/United States
GR  - R01 HD005751/HD/NICHD NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
DEP - 20080514
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Estrogens)
RN  - 0 (Potassium Channels)
RN  - 1WS297W6MV (Phenylephrine)
RN  - 4TI98Z838E (Estradiol)
RN  - 66-40-0 (Tetraethylammonium)
RN  - BH3B64OKL9 (4-Aminopyridine)
RN  - X4W3ENH1CV (Norepinephrine)
SB  - IM
MH  - 4-Aminopyridine/chemistry
MH  - Animals
MH  - Electrophysiology/methods
MH  - Estradiol/*pharmacology
MH  - Estrogens/metabolism
MH  - Female
MH  - Hypothalamus/*pathology
MH  - Neurons/metabolism
MH  - Norepinephrine/*pharmacology
MH  - Patch-Clamp Techniques
MH  - Phenylephrine/*pharmacology
MH  - Potassium Channels/chemistry
MH  - Rats
MH  - Tetraethylammonium/chemistry
MH  - Ventromedial Hypothalamic Nucleus/*pathology
PMC - PMC2438250
COIS- The authors declare no conflict of interest.
EDAT- 2008/05/16 09:00
MHDA- 2008/06/25 09:00
PMCR- 2008/11/20
CRDT- 2008/05/16 09:00
PHST- 2008/05/16 09:00 [pubmed]
PHST- 2008/06/25 09:00 [medline]
PHST- 2008/05/16 09:00 [entrez]
PHST- 2008/11/20 00:00 [pmc-release]
AID - 0802760105 [pii]
AID - 0367 [pii]
AID - 10.1073/pnas.0802760105 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 2008 May 20;105(20):7333-8. doi: 
      10.1073/pnas.0802760105. Epub 2008 May 14.