[Minocycline reduces hyperpolarization-activated current in rat substantia gelatinosa neurons].
OBJECTIVE
To investigate the effect of minocycline on hyperpolarization-activated current (Ih) in the substantia gelatinosa (SG) neurons in rat spinal dorsal horn.


METHODS
In vitro spinal cord transverse slices were prepared from 3-5-week-old male Sprague-Dawley rats. Using whole-cell patch clamp technique, Ih currents were recorded before and after bath application of minocycline (1-300 µmol/L) to the SG neurons.


RESULTS
Ih currents were observed in nearly 50% of the recorded neurons, and were blocked by Ih blocker CsCl and ZD7288. Minocycline rapidly and reversibly reduced the amplitude of Ih and decreased the current density in a concentration-dependent manner with an IC50 of 34 µmol/L.


CONCLUSIONS
Minocycline suppresses the excitability of SG neurons through inhibiting the amplitude and current density of Ih and thereby contributes to pain modulation.
Department of Pain Clinic, First Affiliated Hospital of Nanchang University, Nanchang 330006, China. E-mail: zhumengye0403@163.com.
Mengye
M
Zhu
Nana
N
Liu
Sicong
S
Peng
Lingchao
L
Li
Daying
D
Zhang
Tao
T
Liu
D000818:Animals; D008297:Male; D008911:Minocycline / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects*; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D013376:Substantia Gelatinosa / Q000166:cytology*
D008911:Minocycline