Prostaglandin E2 excites neurons of the nucleus tractus solitarius by activating cation channels.
Nucleus tractus solitarius (NTS) has a high density of prostaglandin E2 (PGE2)-binding sites. Action of PGE2 (10(-9)-10(-6) M) was tested on neurons in a NTS slice with patch-clamp recording under synaptic blockade. PGE2 raised the firing rate in approximately half of the neurons in cell-attached patch mode. In whole-cell current clamp, PGE2 depolarized membrane potential accompanied by an increase in firing rate. In whole-cell voltage clamp (-58 mV), PGE2 induced the inward current with an increase in conductance. The current was linearly related to voltage from -100 mV to -10 mV and suppressed between -10 mV and 20 mV. The current-voltage curve remained similar under low external Cl- or high internal Cl- conditions and after external Na+ was replaced by Cs+. It is concluded that PGE2 excites NTS neurons by activating cation conductance.
Matsumura
K
K
Subfemtomole Biorecognition Project, Research Development Corporation of Japan.
Watanabe
Y
Y
Onoe
H
H
Watanabe
Y
Y
Tanaka
S
S
Shiraki
T
T
Kobayashi
S
S
D000818:Animals; D002412:Cations / Q000378:metabolism; D015232:Dinoprostone / Q000494:pharmacology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D051381:Rats; D017552:Solitary Nucleus / Q000166:cytology / Q000187:drug effects*
D002412:Cations; D007473:Ion Channels; D015232:Dinoprostone