Long-term potentiation in the visual cortex requires both nitric oxide receptor guanylyl cyclases.
The role of nitric oxide (NO)/cGMP signaling in long-term potentiation (LTP) has been a lingering matter of debate. Within the cascade, the NO receptor guanylyl cyclase (GC), the cGMP-forming enzyme that is stimulated by NO, plays a key role. Two isoforms of GC (alpha2-GC, alpha1-GC) exist. To evaluate their contribution to synaptic plasticity, we analyzed knock-out mice lacking either one of the GC isoforms. We found that LTP induced in the visual cortex is NO dependent in the wild-type mice, absent in either of the GC isoform-deficient mice, and restored with application of a cGMP analog in both strains. The requirement of both NO receptor GCs for LTP indicates the existence of two distinct NO/cGMP-mediated pathways, which have to work in concert for expression of LTP.
Haghikia
Arash
A
Faculty of Medicine, Institute of Physiology, Department of Neurophysiology, Ruhr-University Bochum, D-44780 Bochum, Germany.
Mergia
Evanthia
E
Friebe
Andreas
A
Eysel
Ulf T
UT
Koesling
Doris
D
Mittmann
Thomas
T
D000818:Animals; D005260:Female; D006162:Guanylate Cyclase / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D007527:Isoenzymes / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D017774:Long-Term Potentiation / Q000235:genetics / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009569:Nitric Oxide / Q000378:metabolism* / Q000502:physiology; D018160:Receptors, Cytoplasmic and Nuclear / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D000071756:Soluble Guanylyl Cyclase; D014793:Visual Cortex / Q000201:enzymology*
D007527:Isoenzymes; D018160:Receptors, Cytoplasmic and Nuclear; D009569:Nitric Oxide; D006162:Guanylate Cyclase; D000071756:Soluble Guanylyl Cyclase