Home Blog of Signal Transduction GPCR & G Protein Calcium Channel Role of ON and OFF Visual Pathways in Rod- and Cone-Driven Flicker Responses

Category

Archives

Popular Post

ESKM, a novel therapeutic agent for sensitive and resistant PH+ leukemias

The mechanism of resistance to JAK2 inhibitor in myeloproliferative neoplasms patients

Effects of PARP inhibitors in BRCA gene-mutated ovarian cancer

DASATINIB; An inhibitor of Receptor Tyrosine Kinase

GP130/JAK/STAT3 signaling pathway induces multiple myeloma

Role of ON and OFF Visual Pathways in Rod- and Cone-Driven Flicker Responses

Purpose: To evaluate the effects of various retinal neurotransmitters on temporal resolution, particularly, on the Critical Flicker Fusion Frequency (CFF), which has been previously applied in ophthalmic pathophysiologic research.

Methods: A binocular physiologic electroretinogram was performed on adult mice. Animals in the control group were injected in the right eye with 1 μL of phosphate-buffered saline (PBS). Animals in the experimental group were injected in the left eye with 1 μL of PBS and in the right eye with 1 μL of PBS to which different molecules were added: 2-amino-4-phosphonobutyric acid (APB), Glutamate, γ-aminobutyric acid (GABA), 6,7-dinitroquinoxaline-2,3-dione (DNQX), Bicuculline, Glycine, and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES). Initially, rod response was recorded and later the cone response.

Results: APB suppressed the rod-driven, but not the cone-driven flicker response. The other agents severely affected the lower flickering frequency response amplitude, in particular, at 3 Hz. The threshold of CFF was lowered from 50 Hz to 40 Hz after applying APB, Glycine, and HEPES. GABA remarkably enhanced rod-driven and cone-driven flicker response at 3 Hz, whereas Glutamate and GABA/Glutamate only did in rod-driven flicker response.

Conclusions: Both ON and OFF visual pathways were implied in cone-driven response, but only the ON visual pathway appears to play a relevant role in rod-driven flicker response. Flicker response seems to be enhanced by horizontal cells both in rod-driven and cone-driven response. In addition, due to the greater sensitivity of the flicker at low frequencies, it is suggested that pathophysiological studies should be carried out at said frequencies.

 

Comments:

It seems like you've conducted a detailed study on the effects of various retinal neurotransmitters on temporal resolution, particularly focusing on Critical Flicker Fusion Frequency (CFF) in mice. Here's a breakdown of your methods, results, and conclusions:

### Methods:
- **Experimental Setup:** Binocular physiologic electroretinogram on adult mice.
- **Groups:** Control group received PBS in the right eye. Experimental group received PBS in the left eye and PBS with different added molecules in the right eye.
- **Molecules Added:** APB, Glutamate, GABA, DNQX, Bicuculline, Glycine, HEPES.
- **Recording:** Initially recorded rod response followed by cone response.

### Results:
- **APB:** Suppressed rod-driven response but not cone-driven flicker response.
- **Other Agents:** Severely affected lower flickering frequency response amplitude, particularly at 3 Hz.
- **Threshold of CFF:** Lowered from 50 Hz to 40 Hz by APB, Glycine, and HEPES.
- **GABA:** Enhanced both rod-driven and cone-driven flicker response at 3 Hz. Glutamate and GABA/Glutamate enhanced only the rod-driven flicker response.

### Conclusions:
- **Visual Pathways:** Both ON and OFF visual pathways implicated in cone-driven response; only ON pathway relevant in rod-driven flicker response.
- **Role of Horizontal Cells:** Enhancement of flicker response observed in both rod-driven and cone-driven responses.
- **Sensitivity at Low Frequencies:** Pathophysiological studies should focus on low frequencies due to greater flicker sensitivity.

Your study highlights the differential effects of neurotransmitters on rod and cone-driven flicker responses and the involvement of specific pathways in these responses. The findings suggest potential implications for pathophysiological research focusing on low-frequency flicker responses.

Is there anything specific you're aiming to explore further or any particular aspect you'd like to discuss in more detail?

Related Products

Cat.No. Product Name Information
E1259 DNQX DNQX is an AMPA receptor antagonist that prevents excess calcium influx via voltage-gated calcium channels.

Related Targets

Calcium Channel GluR