[The mechanism on hyperpolarization of membrane potential induced by adenosine in frog melanotrophs].
It has been previously shown that the activation of A1 adenosine receptors in frog melanotroph induced a hyperpolarization accompanied by blockage of spontaneous action potentials. In the present report, we explored mechanisms underlying the above phenomenon using the patch-clamp technique in whole-cell and cell-attached configuration. The result showed that adenosine could increase the opening of non-voltage-activated potassium channels leading to hyperpolarization, but an inward cation current activated by hyperpolarizing pulse was not involved.
Mei
Y A
YA
Department of Physiology and Biophysics, Li Ren Laboratory, Fudan University, Shanghai 200433.
Vaudry
H
H
Cazin
L
L
D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000378:metabolism / Q000502:physiology*; D008564:Membrane Potentials; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000187:drug effects*; D011898:Ranidae; D018047:Receptors, Purinergic P1 / Q000378:metabolism
D015221:Potassium Channels; D018047:Receptors, Purinergic P1; D009074:Melanocyte-Stimulating Hormones; D000241:Adenosine