Opposite modulatory effects of substance P on GABA-and 5-HT-activated currents in the same sensory neurons / 生理学报
Acta Physiologica Sinica
;
(6): 703-707, 2004.
Article
in English
| WPRIM
| ID: wpr-352711
ABSTRACT
The modulation by substance P of gamma-aminobutyric acid (GABA)- and 5-hydroxytryptamine (5-HT)-activated currents (I(GABA) and I(5-HT)) was studied by using patch-clamp technique in rat trigeminal ganglion (TG) neurons. The majority of neurons examined responded to GABA and 5-HT with inward currents in the same cells (63.8%, 30/47). In 22 out of 30 neurons sensitive to both GABA and 5-HT, pretreatment with substance P (SP, 0.01 micromol/L) suppressed I(GABA) by (35.7 +/-6.1)% and enhanced I(5-HT) by (65.2 +/- 8.7)%. GR 82334, a potent and specific antagonist of NK1 tachykinin receptor, reversibly blocked the modulatory effects of SP. The SP modulation on I(GABA) and I(5-HT) was also abolished by intracellular dialysis of GDP-beta-S, a non-hydrolyzable GDP analog, or GF 109203X, a selective protein kinase C inhibitor. These results suggest that SP exerts opposite modulatory actions on GABA(A) receptor and 5-HT3 receptor activity of the same primary sensory neuron via the same intracellular signal transduction pathway.
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Pharmacology
/
Physiology
/
Serotonin Antagonists
/
Serotonin
/
Substance P
/
Trigeminal Ganglion
/
Rats, Sprague-Dawley
/
Patch-Clamp Techniques
/
GABA Antagonists
/
Gamma-Aminobutyric Acid
Limits:
Animals
Language:
English
Journal:
Acta Physiologica Sinica
Year:
2004
Type:
Article
Similar
MEDLINE
...
LILACS
LIS