Dark-induced supersensitivity of dopamine D-1 and D-2 receptors in rat retina.
Light deprivation of rat retina leads to a rapid (within 6 h) development of a state of supersensitivity (upregulation) of dopamine D-1 receptors (positively coupled to adenylate cyclase), which are essentially involved in the modulation by light of the electrical activity and communication between horizontal cells. In contrast, the supersensitivity of D-2 receptors (negatively coupled to cAMP generating system) appears to develop only after 2 days (better after 4 days) of dark adaptation, although these receptors are linked to multiple light-dependent retinal functions. These results suggest the existence of different mechanisms of sensory adaptation for these two subtypes of dopamine receptors.
Nowak
J Z
JZ
Department of Biogenic Amines, Polish Academy of Sciences, Lodz.
Sek
B
B
Schorderet
M
M
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism*; D003624:Darkness; D004298:Dopamine / Q000494:pharmacology*; D008027:Light; D008297:Male; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D012160:Retina / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D013469:Sulpiride / Q000494:pharmacology*
D011506:Proteins; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D005576:Colforsin; D013469:Sulpiride; D000242:Cyclic AMP; D015056:1-Methyl-3-isobutylxanthine; D004298:Dopamine