INVESTIGADORES
FAILLACE Maria paula
artículos
Título:
Daily variations in cyclic GMP, Guanylate Cyclase and Phosphodiesterase in the golden hamster retina.
Autor/es:
8. FAILLACE MP, KELLER SARMIENTO MI, ROSENSTEIN RE
Revista:
VISION RESEARCH
Editorial:
Elsevier
Referencias:
Año: 1996 vol. 36 p. 1365 - 1369
ISSN:
0042-6989
Resumen:
Daily variations in cGMP, guanylate cyclase and phosphodiesterase
activity in golden hamster retina were studied. Cyclic GMP content
exhibited significant variations throughout the 24-hr cycle with
maximal values during the dark phase. In order to establish the
relative participation of nucleotide synthesis and breakdown during a
24-hr cycle, guanylate cyclase and phosphodiesterase activity were
measured in hamsters killed at eight intervals. Guanylate cyclase
activity increased at night, peaking at 22.00 hr. Phosphodiesterase
activity did not change significantly throughout the light-dark cycle.
Light exposure during the night inhibited the nocturnal increase in
cGMP content and guanylate cyclase activity, while phosphodiesterase
remained unchanged. From these results, it might be presumed that in
response to continuous (in a range of hr) light or dark stimuli, the
retina would process the photic signal in a different way from that in
the short term (in a range of msec).