Journal Article
Título | Evidence that olfactory sensitivities to calcium and sodium are mediated by different mechanisms in the goldfish Carassius auratus. |
Publication Type | Journal Article |
Authors | Hubbard, PC, Canario, AVM |
Year of Publication | 2007 |
Journal | Neurosci Lett |
Volume | 414 |
Questão | 1 |
Date Published | 2007 Feb 27 |
Pagination | 90-3 |
ISSN | 0304-3940 |
Palavras-chave | Action Potentials, Animals, Calcium, Dose-Response Relationship, Drug, Electroencephalography, Goldfish, Neurons, Afferent, Olfactory Bulb, Olfactory Mucosa, Olfactory Nerve, Sensory Thresholds, Smell, Sodium |
Abstract | The current study investigated whether the olfactory sensitivity to Ca2+ and Na+ is mediated by the same mechanism in the goldfish, a freshwater teleost. The olfactory responses, as assessed by recording the electro-encephalogram (EEG) from the olfactory bulb, to changes in external [Ca2+] and to [Na+] were recorded in the absence and presence of increasing concentrations of the other ion. Low concentrations of Na+ (0-1.0mM) had no significant effects on the olfactory response to changes in [Ca2+] in terms of EC50, Imax or Hill co-efficient (n=8). A relatively high concentration of Na+ (10mM) significantly reduced the Imax and increased the EC50. One hundred millimolars Na+ reduced the olfactory response to Ca2+ to undetectable levels. Conversely, low concentrations of Ca2+ (0.1 and 1.0mM) significantly attenuated the olfactory response to changes in environmental [Na+], reducing the amplitude of response and increasing the threshold of detection (n=7). However, a high concentration of Ca2+ (10mM) failed to attenuate the olfactory response to Na+ completely. Taken together, these results suggest that, at normal environmental concentrations of these ions, Ca2+ and Na+ are detected by distinct and separate cellular mechanisms. However, there seems to be a degree of overlap between the two mechanisms. The exact mechanisms involved, and their biological roles, remain to be established. |
DOI | 10.1016/j.neulet.2006.12.007 |
Sapientia | |
Alternate Journal | Neurosci. Lett. |
PubMed ID | 17196333 |