Meeting Abstract
P2.75 Friday, Jan. 4 The effects of TPep, ACh, 5HT, and Dopamine on the Ciliary Transport Rate of a Chemosensory Organ in Tritonia diomedea TRUMAN , Gary A*; OHMES, Lucas B; CAIN, Shaun D; Eastern Oregon University; Eastern Oregon University; Eastern Oregon University trumang@eou.edu
The neural circuits that control behavior have been the focus of neuroethology for many years. Recently, it has become apparent that many multi-functional networks exist. One of these networks, the swim CPG of Tritonia diomedea, controls two very different modes of locomotion. When the network is configured to produce rhythmic output, the CPG recruits motoneurons that initiate swimming. In contrast, the tonic firing of a subset of CPG neurons initiates ciliary-based crawling, which is the primary mode of locomotion in this animal. One of the pathways used by the CPG to regulate crawling is through an excitiary monosyaptic coupling to a pair of cilio-motor giant neurons (Pd5 and Pd6). The CPG communicates with a third giant neuron (Pd7). Although this pathway is inhibitory, Pd7 shares many characteristics of Pd5 and P6. Based on the morphology of Pd7 and the known neurotransmitters produced by this cell (TPep and ACh), we hypothesize that Pd7 is involved in controlling the ventral ciliated surface of the lateral tip of the oral veil (here called Murray�s Organ), which is a primary sensory organ. Although this is a sensory organ, the cilia on the ventral surface are motor and likely serve to bring odors from the substrate to the olfactory receptors lining Murray�s Organ. In this study we tested the effect of known cilio-regulatory neurotransmitters on the transport rate of the motor cilia. Preliminary results indicate that both TPep and 5HT increase transport rate, while ACh and DA either slows transport rate or has no effect. This is consistent with our hypothesis that Pd7 is involved in the activity of cilia in Murray�s Organ. This would extend the function of the CPG to regulating the control of incoming sensory cues during both swimming and crawling.
