PMID- 24313753
OWN - NLM
STAT- MEDLINE
DCOM- 20150110
LR  - 20140116
IS  - 1365-2826 (Electronic)
IS  - 0953-8194 (Linking)
VI  - 26
IP  - 1
DP  - 2014 Jan
TI  - Attenuated benzodiazepine-sensitive tonic GABAA currents of supraoptic 
      magnocellular neuroendocrine cells in 24-h water-deprived rats.
PG  - 26-34
LID - 10.1111/jne.12123 [doi]
AB  - In supraoptic nucleus (SON) magnocellular neurosecretory cells (MNCs), gamma-GABA, 
      via activation of GABAA receptors (GABAA Rs), mediates persistent tonic 
      inhibitory currents (Itonic ), as well as conventional inhibitory postsynaptic 
      currents (IPSCs, Iphasic ). In the present study, we examined the functional 
      significance of Itonic in SON MNCs challenged by 24-h water deprivation (24WD). 
      Although the main characteristics of spontaneous IPSCs were similar in 24WD 
      compared to euhydrated (EU) rats, Itonic , measured by bicuculline (BIC)-induced 
      Iholding shifts, was significantly smaller in 24WD compared to EU rats (P < 
      0.05). Propofol and diazepam prolonged IPSC decay time to a similar extent in 
      both groups but induced less Itonic in 24WD compared to EU rats, suggesting a 
      selective decrease in GABAA receptors mediating Itonic over Iphasic in 24WD rats. 
      THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol), a preferential delta subunit 
      agonist, and L-655,708, a GABAA receptor alpha5 subunit selective 
      imidazobenzodiazepine, caused a significantly smaller inward and outward shift in 
      Iholding , respectively, in 24WD compared to EU rats (P < 0.05 in both cases), 
      suggesting an overall decrease in the alpha5 subunit-containing GABAA Rs and the delta 
      subunit-containing receptors mediating Itonic in 24WD animals. Consistent with a 
      decrease in 24WD Itonic , bath application of GABA induced significantly less 
      inhibition of the neuronal firing activity in 24WD compared to EU SON MNCs (P < 
      0.05). Taken together, the results of the present study indicate a selective 
      decrease in GABAA Rs functions mediating Itonic as opposed to those mediating 
      Iphasic in SON MNCs, demonstrating the functional significance of Itonic with 
      respect to increasing neuronal excitability and hormone secretion in 24WD rats.
CI  - (c) 2014 British Society for Neuroendocrinology.
FAU - Pandit, S
AU  - Pandit S
AD  - Department of Physiology, School of Medicine, Brain Research Institute, Chungnam 
      National University, Jung-gu, Daejeon, Korea.
FAU - Song, J G
AU  - Song JG
FAU - Kim, Y J
AU  - Kim YJ
FAU - Jeong, J A
AU  - Jeong JA
FAU - Jo, J Y
AU  - Jo JY
FAU - Lee, G S
AU  - Lee GS
FAU - Kim, H-W
AU  - Kim HW
FAU - Jeon, B H
AU  - Jeon BH
FAU - Lee, J U
AU  - Lee JU
FAU - Park, J B
AU  - Park JB
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Neuroendocrinol
JT  - Journal of neuroendocrinology
JID - 8913461
RN  - 0 (GABA Agonists)
RN  - 0 (GABA-A Receptor Antagonists)
RN  - 0 (Hypnotics and Sedatives)
RN  - 0 (Imidazoles)
RN  - 0 (Isoxazoles)
RN  - 0 (L 655,708)
RN  - 0 (Protein Subunits)
RN  - 0 (Receptors, GABA-A)
RN  - 56-12-2 (gamma-Aminobutyric Acid)
RN  - K1M5RVL18S (gaboxadol)
RN  - Q3JTX2Q7TU (Diazepam)
RN  - Y37615DVKC (Bicuculline)
RN  - YI7VU623SF (Propofol)
SB  - IM
MH  - Animals
MH  - Bicuculline/pharmacology
MH  - Diazepam/pharmacology
MH  - GABA Agonists/pharmacology
MH  - GABA-A Receptor Antagonists/pharmacology
MH  - Hypnotics and Sedatives/pharmacology
MH  - Imidazoles/pharmacology
MH  - Inhibitory Postsynaptic Potentials/drug effects/*physiology
MH  - Isoxazoles/pharmacology
MH  - Male
MH  - Neuroendocrine Cells/drug effects/*physiology
MH  - Propofol/pharmacology
MH  - Protein Subunits/drug effects/physiology
MH  - Rats
MH  - Receptors, GABA-A/*physiology
MH  - Supraoptic Nucleus/*cytology/drug effects/*physiology
MH  - Water Deprivation/*physiology
MH  - gamma-Aminobutyric Acid/pharmacology
OTO - NOTNLM
OT  - oxytocin
OT  - supraoptic nucleus
OT  - tonic GABAA current
OT  - vasopressin
OT  - water deprivation
EDAT- 2013/12/10 06:00
MHDA- 2015/01/13 06:00
CRDT- 2013/12/10 06:00
PHST- 2013/04/30 00:00 [received]
PHST- 2013/11/05 00:00 [revised]
PHST- 2013/12/01 00:00 [accepted]
PHST- 2013/12/10 06:00 [entrez]
PHST- 2013/12/10 06:00 [pubmed]
PHST- 2015/01/13 06:00 [medline]
AID - 10.1111/jne.12123 [doi]
PST - ppublish
SO  - J Neuroendocrinol. 2014 Jan;26(1):26-34. doi: 10.1111/jne.12123.