Abstract
Transmitter release from photoreceptors is decreased by light, resulting in a conductance increase in depolarizing bipolar cells. Addition of exogenous cGMP through a patch pipette to depolarizing bipolar cells from slices of dark-adapted tiger salamander retina resulted in an enhancement of the light response. This enhancement was blocked by GTP-γ-S and dipyridamole, an inhibitor of phosphodiesterase. GTP-γ-S and dipyridamole also blocked responses to exogenously applied 2-amino-4-phosphonobutyrate (APB), the glutamate agonist selective for this receptor. These data support the hypothesis that the postsynaptic receptor is linked via a G protein to a phosphodiesterase. The binding of glutamate or APB to the receptor suppresses a cGMP-activated current by increasing the rate of cyclic nucleotide hydrolysis.
Original language | English (US) |
---|---|
Pages (from-to) | 677-683 |
Number of pages | 7 |
Journal | Neuron |
Volume | 7 |
Issue number | 4 |
DOIs | |
State | Published - Oct 1991 |
Externally published | Yes |
ASJC Scopus subject areas
- General Neuroscience