PMID- 9875364
OWN - NLM
STAT- MEDLINE
DCOM- 19990114
LR  - 20191210
IS  - 0953-816X (Print)
IS  - 0953-816X (Linking)
VI  - 10
IP  - 12
DP  - 1998 Dec
TI  - Different regions of the periaqueductal grey are involved differently in the 
      expression and conditioned inhibition of fear-potentiated startle.
PG  - 3876-84
AB  - The fear-potentiated startle paradigm is a useful model for investigating the 
      neural systems underlying the mediation and modulation of fear and anxiety. A 
      series of previous studies showed that the periaqueductal grey is involved in the 
      expression and inhibition of fear-potentiated startle, but it was uncertain 
      whether the different columns of the periaqueductal grey play different roles. In 
      the present study, picrotoxin, a GABAA (gamma-aminobutyric acid) chloride-channel 
      blocker, was injected into the dorsal, lateral and ventrolateral columns of the 
      periaqueductal grey in order to examine the effects of neural disinhibition on 
      expression and conditioned inhibition of fear-potentiated startle. Picrotoxin 
      injections into the lateral periaqueductal grey increase potentiation of the 
      startle response by conditioned fear, injections into the ventrolateral 
      periaqueductal grey block fear-potentiated startle. Picrotoxin injections into 
      the dorsal periaqueductal grey decreased conditioned inhibition but did not 
      affect expression of fear-potentiated startle. The baseline startle amplitude was 
      not influenced by picrotoxin injections into the different columns of the 
      periaqueductal grey. Picrotoxin injections into neighbouring brain areas did not 
      have any effect on baseline startle amplitude nor did they have an effect on 
      expression or conditioned inhibition of fear-potentiated startle. Based on the 
      present results, the possible pathways underlying the expression and conditioned 
      inhibition of fear-potentiated startle in rats are discussed.
FAU - Fendt, M
AU  - Fendt M
AD  - Universitat Tubingen, Germany. markus.fendt@uni-tuebingen.de
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - France
TA  - Eur J Neurosci
JT  - The European journal of neuroscience
JID - 8918110
RN  - 0 (Chloride Channels)
RN  - 0 (GABA Antagonists)
RN  - 0 (GABA-A Receptor Antagonists)
RN  - 124-87-8 (Picrotoxin)
SB  - IM
MH  - Animals
MH  - Chloride Channels/antagonists & inhibitors
MH  - Conditioning, Psychological/drug effects/*physiology
MH  - *Fear
MH  - GABA Antagonists/pharmacology
MH  - GABA-A Receptor Antagonists
MH  - Male
MH  - Neural Inhibition/drug effects/*physiology
MH  - Periaqueductal Gray/chemistry/*physiology
MH  - Picrotoxin/pharmacology
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Reflex, Startle/drug effects/*physiology
EDAT- 1999/01/06 00:00
MHDA- 1999/01/06 00:01
CRDT- 1999/01/06 00:00
PHST- 1999/01/06 00:00 [pubmed]
PHST- 1999/01/06 00:01 [medline]
PHST- 1999/01/06 00:00 [entrez]
AID - 10.1046/j.1460-9568.1998.00395.x [doi]
PST - ppublish
SO  - Eur J Neurosci. 1998 Dec;10(12):3876-84. doi: 10.1046/j.1460-9568.1998.00395.x.