Related Experiment Videos
Zinc modulates the electro-olfactogram of the frog
T Ishimaru1, T Tsukatani, T Miwa
1Department of Otorhinolaryngology, School of Medicine, Kanazawa University, 13-1, Takara-machi, Kanazawa, Japan. ishimar@orl.m.kanazawa-u.ac.jp
Auris, Nasus, Larynx
|May 16, 2000
Summary
Zinc ions (Zn2+) attenuate electro-olfactograms (EOGs) in frog olfactory mucosa. This suggests zinc acts as a modulator in olfactory reception by potentially blocking cAMP-dependent channels.
Area of Science:
- Neuroscience
- Sensory Biology
- Biochemistry
Background:
- Zinc is implicated in olfaction, but its precise role remains unclear.
- High concentrations of zinc in olfactory mucosa suggest a potential neuromodulatory function, similar to its role in the hippocampus.
- Investigating the acute effects of zinc on olfactory mucosa is crucial for understanding its contribution to smell.
Purpose of the Study:
- To elucidate the acute effects of zinc ions (Zn2+) on olfactory mucosa function.
- To determine if Zn2+ modulates olfactory responses by recording electro-olfactograms (EOGs).
Main Methods:
- Isolated bullfrog olfactory mucosa was used for EOG recordings.
- The effects of 25 microM ZnSO4 on EOGs were assessed.
- Stimulants tested included odorants (n-amyl acetate, menthone) and cAMP pathway activators (forskolin, IBMX).
Main Results:
- Zn2+ (25 microM) significantly attenuated EOGs elicited by odorants, forskolin, and IBMX.
- Attenuation ratios ranged from 0.48 to 0.68, indicating a broad inhibitory effect.
- The observed attenuations were reversible, suggesting a dynamic interaction with olfactory cells.
Conclusions:
- Micromolar concentrations of Zn2+ attenuate frog olfactory EOGs.
- Zn2+ likely acts as a modulator in olfactory reception.
- Results suggest Zn2+ may block cAMP-dependent transduction channels in olfactory cells.