Changes in the properties of the modulatory cerebral giant cells contribute to aging in the feeding system of Lymnaea


Patel, B., Arundell, Martin, Allen, M., Gard, P., Ohare, D., Parker, K. and Yeoman, M. (2006) Changes in the properties of the modulatory cerebral giant cells contribute to aging in the feeding system of Lymnaea. Neurobiology of Aging, 27, (12), 1892-1901. (doi:10.1016/j.neurobiolaging.2005.09.041).

Download

Full text not available from this repository.

Description/Abstract

This study examined whether electrophysiological changes in the endogenous properties and connectivity of the modulatory serotonergic cerebral giant cells (CGCs) contributed to the age-related changes in feeding behavior of the pond snail, Lymnaea. With increasing age there was a decrease in spontaneous CGC firing rates and decreased excitability of the CGCs to both chemosensory stimulation (0.05M sucrose applied to the lips) and direct intracellular current injection. These changes could be accounted for by a decrease in the input resistance of the neuron and an increase in the amplitude and the duration of the after-hyperpolarization. Decreases were also seen in the % of CGC pairs that were electrically coupled causing asynchronous firing. Together these changes would tend to reduce the ability of the CGCs to gate and control the frequency of the feeding behavior. Part of the ability of the CGCs to gate and frequency control the feeding network is to provide a background level of excitation to the feeding motor neurons. Recordings from B1 and B4 motor neurons showed an age-related hyperpolarization of the resting membrane potential consistent with a deficit in CGC function. Increases were seen in the strength of the evoked CGC→B1 connection, however, this increase failed to compensate for the deficits in CGC excitability. In summary, age-related changes in the properties of the CGCs were consistent with them contributing to the age-related changes in feeding behavior seen in Lymnaea.

Item Type: Article
ISSNs: 0197-4580 (print)
Keywords: neuronal aging, serotonin, feeding system, modulation, mollusk
Divisions: University Structure - Pre August 2011 > School of Biological Sciences
ePrint ID: 155863
Date Deposited: 22 Jun 2010 12:04
Last Modified: 27 Mar 2014 19:13
URI: http://eprints.soton.ac.uk/id/eprint/155863

Actions (login required)

View Item View Item