Published online by Cambridge University Press: 09 April 2001
To investigate the physiology and plasticity of mixed rod–cone ON-bipolar cells (Mb) in the goldfish retina, we established a slice preparation which allows us to optically monitor the synaptic activity of bipolar cell axon terminals. We used the styryl dye FM1-43 which is incorporated into active axon terminals due to synaptic vesicle cycling and thus reflects synaptic activity. Different activity states of the axon terminals were revealed when slices prepared from light-adapted retinae were incubated in the presence of FM1-43 under various conditions. Depolarizing high K+ Ringer (50 mM) and the gamma-butyric acid (GABA) antagonist bicuculline (100 μM) resulted in more than two-fold increase in the number of stained terminals compared to slices stained in normal Ringer. In contrast, GABA treatment (0.5 mM) reduced the frequency of stained terminals. Thus, in light-adapted retinal slices the synaptic activity of Mb axon terminals can be modulated towards higher and lower activity states. The fact that the GABA antagonist bicuculline had similar effects as stimulatory high K+ Ringer suggests that inhibitory control is an important component in the regulation of synaptic activity and transmitter release in Mb terminals.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.
To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.