Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Cyclic GMP diffusion coefficient in rod photoreceptor outer segments

Y Koutalos1, K Nakatani, K W Yau

  • 1Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.

Biophysical Journal
|January 1, 1995
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Fine needle biopsy guided by contrast-enhanced harmonic versus conventional endoscopic ultrasound with macroscopic on-site evaluation for solid pancreatic lesions: abridged secondary publication.

Hong Kong medical journal = Xianggang yi xue za zhi·2026
Same author

When qualitative data contradict quantitative data: diabetes distress in the Chinese-Canadian community.

Diabetic medicine : a journal of the British Diabetic Association·2019
Same author

Intravenous Administration of Tacrolimus Stabilizes Control of Blood Concentration Regardless of CYP3A5 Polymorphism in Living Donor Liver Transplantation: Comparison of Intravenous Infusion and Oral Administration in Early Postoperative Period.

Transplantation proceedings·2018
Same author

Fluorescence turn-on hairpin-probe PCR.

Chemical communications (Cambridge, England)·2017
Same author

Emergency femoral hernia repair: 13-year retrospective comparison of the three classical open surgical approaches.

Hernia : the journal of hernias and abdominal wall surgery·2016
Same author

A 2,7-diamino-1,4,8-triazanaphthalene derivative selectively binds to cytosine bulge DNA only at a weakly acidic pH.

Organic & biomolecular chemistry·2016
Same journal

Anisotropic unbinding and location-dependent hovering of a kinesin motor head over microtubule.

Biophysical journal·2026
Same journal

Kinesin-5/Cut7 C-terminal tail phosphorylation influence on motor regulation through multi-scale molecular modeling.

Biophysical journal·2026
Same journal

Dynamic conformations of fluorophores on self-labeling protein tags.

Biophysical journal·2026
Same journal

Different actions of RyR2 open and closed channel block explained by a multiscale Ca<sup>2+</sup> release model.

Biophysical journal·2026
Same journal

Membrane Environment Sets the Functional pK<sub>a</sub> of Ionizable Lipids.

Biophysical journal·2026
Same journal

Distinguishable spreading dynamics in microbial communities.

Biophysical journal·2026
See all related articles

Cyclic GMP (cGMP) diffusion in retinal rod cells is slower than expected, impacting light response. This study measured cGMP diffusion coefficients in bullfrog and tiger salamander rods, revealing slower rates crucial for understanding phototransduction.

Area of Science:

  • Vision science
  • Cellular physiology
  • Biophysics

Background:

  • Cyclic GMP (cGMP) is a key intracellular messenger in retinal rod phototransduction.
  • The diffusion of cGMP within the rod outer segment influences the cell's light response.

Purpose of the Study:

  • To measure the cGMP diffusion coefficient in rod outer segments.
  • To understand the contribution of cGMP diffusion to phototransduction.

Main Methods:

  • Utilized truncated rod outer segment preparations from bullfrog and tiger salamander.
  • Measured cGMP diffusion by analyzing cGMP-elicited currents after step changes in bath cGMP concentration.
  • Inhibited cGMP hydrolysis with IBMX to simplify diffusion analysis.

Main Results:

Related Experiment Videos

  • Obtained cGMP diffusion coefficients of ~70 x 10^-8 cm^2/s for bullfrog rods and ~60 x 10^-8 cm^2/s for tiger salamander rods.
  • These values are 6-7 times lower than those in aqueous solution.
  • Diffusion coefficient remained consistent across high and low cGMP concentrations, indicating minimal buffering effects.

Conclusions:

  • cGMP diffuses significantly slower within rod outer segments than in free solution.
  • This reduced diffusion rate is a critical factor in the kinetics of phototransduction.
  • The findings provide essential quantitative data for models of visual signaling.