Adenosine inhibits a GABAB receptor-mediated hyperpolarizing postsynaptic potential in neurons of rat septal nuclei.
Intracellular recordings were made from neurons of rat dorsolateral septal nucleus (DLSN), in vitro. Adenosine and 2-chloroadenosine (1-500 microM) hyperpolarized DLSN neurons and blocked the excitatory postsynaptic potential (EPSP) and the late hyperpolarizing potential (LHP) in the presence of bicuculline. Adenosine did not depress the glutamate-induced potential. Bath-application of adenosine depressed the baclofen-induced potential in 60% of the neurons. Adenosine also inhibited the LHP in the remaining 40% of neurons, while it did not depress the baclofen-induced potential in these neurons. These results indicate that adenosine inhibits the EPSP pre-synaptically whereas it inhibits the LHP both pre- and postsynaptically in rat septal nuclei.
Hasuo
H
H
Department of Physiology, Kurume University School of Medicine, Japan.
Shoji
S
S
Akasu
T
T
Gallagher
J P
JP
D000241:Adenosine / Q000502:physiology*; D000818:Animals; D005071:Evoked Potentials / Q000502:physiology; D066298:In Vitro Techniques; D009474:Neurons / Q000502:physiology*; D051381:Rats; D011963:Receptors, GABA-A / Q000502:physiology*; D012686:Septal Nuclei / Q000502:physiology*
D011963:Receptors, GABA-A; D000241:Adenosine