Submitted to: Society for Neuroscience Abstracts and Proceedings
Publication Type: Other
Publication Acceptance Date: 7/16/2002
Publication Date: 11/2/2002
Citation: Rabin, B.M., Shukitt-Hale, B., Joseph, J.A., Buhler, L.L., Jenkins, D.G., and Eggleston, A.M. Interaction between heavy particle irradiation and age in the disruption of fixed - ratio operant responding in rats. Soc. Neurosci. Abs. 2002, 28, 889.11. Interpretive Summary:
Technical Abstract: Exposing rats to heavy particle irradiation (56Fe) produces a disruption in the functioning of the dopaminergic system and in the behaviors that are mediated by the dopaminergic this system. To some extent the neurochemical and behavioral deficits observed following exposure to 56Fe particles are similar to those that are observed in aged rats. Research by other investigators has shown that rats with 6-OHDA lesions of the striatum have difficulty in responding on a fixed-ratio bar pressing task and that, for rats with partial lesions of the striatum, the deficit becomes more severe as a function of age. The present experiment was designed to determine whether or not similar behavioral effects were observed following exposure to heavy particles and possible interaction with age. Two-month old rats were exposed to 0, 1.0, 1.5, or 2.0 Gy 56Fe particles (1 GeV/n) using the Alternating Gradient Synchrotron at Brookhaven National Laboratory. After exposure the rats were returned to UMBC and trained in a fixed ratio level pressing task (FR-1 to FR-35). When tested 3 months following irradiation, only the rats exposed to 2.0 Gy showed a significant deficit in responding at the higher ratios ( FR-25). When tested 8 months following irradiation, the rats given the lower doses of irradiation, also showed deficits in responding at the higher ratios? what about lower ratios. These results indicate that there is an interaction between the age of the rat and the dose of 56Fe particle irradiation in producing a disruption of dopamine-mediated fixed-ratio lever pressing task.