Section 5
Chapter 4,755

Antennal proprioception in the rock lobster palinurus vulgaris anatomy and physiology of a bi articular chordotonal organ

Rossi Durand, C.; Vedel, J.P.

Journal of Comparative Physiology A Sensory Neural and Behavioral Physiology 145(4): 505-516


Accession: 004754611

Download citation:  

In the antennae of the rock lobster, P. vulgaris, proprioception of the 2 distal joints (J2-J3) is ensured by a single mechanoreceptor, the J2-J3 chordotonal organ (CO J2-J3). The CO J2-J3 is formed by a large connective tissue sheet spanning both joints. On the sheet, 3 groups of sensory cells can be distinguished: a proximal group g1, a medial group g2 and a distal group g3. Because of the triple cuticular insertion of the sheet, CO J2-J3 length is affected differently by J2 and J3 movements. Micrometric observations showed that g1 region length changes reuslt mainly from J2 movements, g3 region from J3 movements and g2 region from both J2 and J3 movements. Electrophysiological study revealed 2 kinds of sensory afferent: sensory neurons exclusively sensitive to joint positions (static sensitivity) and sensory neurons exclusively sensitive to joint movements (dynamic sensitivity), the latter neurons responding to only 1 movement direction (extension or flexion) of the joints. Each kind of sensory neuron can be subdivided into different categories according to its sensitivity to J2 and J3 position and movement: the monoarticular neurons encoding the position or movement of only 1 joint, J2 or J3, or the biarticular neurons, sensitive either to the positions or to the moements of both joints. Some respond to position changes of J2 and J3 in the same direction (homo-directional neurons); some respond to position changes of J2 and J3 in opposite directions; i.e., J2 flexion-J3 extension (hetero-directional neurons). The origin of the different modalities of sensory responses is interpreted according to the localization of the sensory neurons on the CO J2-J3 sheet. CO J2-J3 sensory information is compared with that observed in other chordotonal organs and its role in controlling joint position and movement is discussed.

PDF emailed within 1 workday: $29.90