Meeting Abstract

P2.121  Thursday, Jan. 5  Sensory Motor Integration of Gill Lateral Cilia in the Bivalve Mollusc, Crassostrea virginica AKANDE, P.*; BANDAOGO, Z.; CARROLL, M.A.; CATAPANE, E.J.; Medgar Evers College, Brooklyn, NY; Medgar Evers College, Brooklyn, NY; Medgar Evers College, Brooklyn, NY; Medgar Evers College, Brooklyn, NY patrickbkaka@yahoo.com

Gill lateral cilia of Crassostrea virginica are controlled by serotonergic-dopaminergic innervation from their ganglia. Most bivalves that have been studied also have lateral cilia which respond to serotonin and dopamine indicating a neuro or endocrine mechanism. While the motor aspects of this control have been studied over the years, the sensory side has not and there is limited information available about sensory inputs beyond that of temperature and salinity changes. We examined effects of sensory cues on beating rates of lateral cilia of gill of C. virginica. Cilia beating rates were measured in whole animal preparations. Irritating the mantle rim by brushing with a metal probe caused a 70% drop in beating rates lasting at least 15 min. Shining a light on mantle rim decreased beating by 50%. Applying crab extract reduced beating rates to zero. When the branchial nerve, was cut the crab extract did not have any effect on the cilia. When the cerebrovisceral connective was cut the basal cilia rate was lower than controls and the crab extract was effective in slowing beating rate. Since the mantle rim is a major site of sensory cells in the animal, we excised the rim from the animals and applied crab extract. The absence of the mantle rim prevented the crab extract from affecting beating rates. The study shows a sensory-motor integration of the beating of the lateral cilia which involves the sensory rim of the mantle, and the visceral and cerebral ganglia. It appears the animals may be interpreting the sensory cues as hostile. In their natural environment, they would then close their shells and reduce water pumping rates with a corresponding drop in cilia beating rates.