Tuning of chemoreceptor cells of the second antenna of the American lobster (Homarus americanus) with a comparison of four of its other chemoreceptor organs |
| |
Authors: | Rainer Voigt Jelle Atema |
| |
Institution: | 1. Boston University Marine Program, Marine Biological Laboratory, 02543, Woods Hole, MA, USA
|
| |
Abstract: | 1. |
We determined the spectral tuning properties of 47 chemoreceptor cells of the antenna of Homarus americanus to amino acids and other compounds. Tests with 17 single compounds at 10-4
M showed 40 of 47 cells responded best to hydroxyproline, 4 cells to taurine and 3 cells to betaine. Mean tuning breadth (H-metric) doubled with 10 fold increase in concentration.
| 2. |
In hydroxyproline-best cells the mean threshold for hydroxyproline (Hyp) was found between 10-7
M and 10-8
M. An equimolar mixture of the 17 compounds generated a shallower stimulus-response function with thresholds similar to Hyp function (mixture suppression). Hyp-best cells were relatively narrowly tuned, often with arginine or leucine as second best stimuli.
| 3. |
Thus, physiologically the second antenna of H. americanus is a major chemoreceptor organ. It is more than any of the 5 chemoreceptor organs studied so far dominated by a single best-cell type (Hyp). Receptor cell composition of antennae resembles that of antennules more than legs or maxillipeds. Hyp-best cells in antennae and lateral antennules have similar tuning spectra.
| 4. |
Our cell tuning studies argue for independent receptors for all amino acids tested. We conclude that diversity of receptor cell tuning is created by cell-specific blends of receptors. At the organ level, differences in organ tuning result from different blends of receptor cells.
|
|
| |
Keywords: | Lobster Antenna Chemoreceptor organs Amino acids Concentration dependent tuning |
本文献已被 SpringerLink 等数据库收录! |
|