TY - JOUR

T1 - Chemosensory neurons in the mouthparts of the spiny lobsters Panulirus argus and Panulirus interruptus (Crustacea : Decapoda)

AU - Garm, Anders Lydik

AU - Shabani, Shkelzen

AU - Høeg, Jens Thorvald

AU - Derby, Charles D.

N1 - Keywords: Chemoreceptors; Chemical senses; Gustation; Electrophysiology; Adaptation

PY - 2005

Y1 - 2005

N2 - We studied electrophysiological properties of single chemosensory neurons in the mouthparts of the spiny lobsters Panulirus argus and Panulirus interruptus to complement our growing understanding of the behavioral roles of mouthparts of decapod crustaceans. Food mixtures and 13 single compounds were used to characterize the response specificity, sensitivity, and time course of individual neurons in the endopods of maxilliped 2 and 3. Additional chemoreceptors were found in the mandibular palp and basis of maxilliped 1 but they were not characterized. Neurons were broadly tuned, with the five most potent single compounds being ammonium, adenosine-5'-monophosphate, taurine, glutamate, and aspartate. Cluster analysis indicated that the neurons constitute a heterogeneous population that could be placed into seven groups linked according to their most excitatory compound. These neurons in the mouthparts had concentration-dependent responses, with thresholds between 10-7 and 10-4 M and without saturation even at 10-3 or 10-2 M. They also quickly adapted when exposed to their best compounds at 10-4 and 10-3 M. A comparison of the response properties of these neurons in the mouthparts with those of chemosensory neurons in other crustacean appendages shows that neurons in the mouthparts have relatively broad tuning biased toward detecting and resolving high concentrations. Based on these comparisons, we suggest a functional distinction among the chemosensors on the different appendages: long distance detection by the antennae, precise location and collection by the pereiopods, and detailed assessment of quality by the mouthparts.

AB - We studied electrophysiological properties of single chemosensory neurons in the mouthparts of the spiny lobsters Panulirus argus and Panulirus interruptus to complement our growing understanding of the behavioral roles of mouthparts of decapod crustaceans. Food mixtures and 13 single compounds were used to characterize the response specificity, sensitivity, and time course of individual neurons in the endopods of maxilliped 2 and 3. Additional chemoreceptors were found in the mandibular palp and basis of maxilliped 1 but they were not characterized. Neurons were broadly tuned, with the five most potent single compounds being ammonium, adenosine-5'-monophosphate, taurine, glutamate, and aspartate. Cluster analysis indicated that the neurons constitute a heterogeneous population that could be placed into seven groups linked according to their most excitatory compound. These neurons in the mouthparts had concentration-dependent responses, with thresholds between 10-7 and 10-4 M and without saturation even at 10-3 or 10-2 M. They also quickly adapted when exposed to their best compounds at 10-4 and 10-3 M. A comparison of the response properties of these neurons in the mouthparts with those of chemosensory neurons in other crustacean appendages shows that neurons in the mouthparts have relatively broad tuning biased toward detecting and resolving high concentrations. Based on these comparisons, we suggest a functional distinction among the chemosensors on the different appendages: long distance detection by the antennae, precise location and collection by the pereiopods, and detailed assessment of quality by the mouthparts.

U2 - 10.1016/j.jembe.2004.08.016

DO - 10.1016/j.jembe.2004.08.016

M3 - Journal article

VL - 314

SP - 175

EP - 186

JO - Journal of Experimental Marine Biology and Ecology

JF - Journal of Experimental Marine Biology and Ecology

SN - 0022-0981

IS - 2

ER -