Meeting Abstract

P2.149  Monday, Jan. 5  EFFECT OF EXERCISE AND ENVIRONMENT ON THE AUTONOMIC RESPONSE IN CRAYFISH, PROCAMBARUS CLARKII COOPER, Robin L.*; BIERBOWER, Sonya M.; Univ of KY; Univ of KY RLCOOP1@email.uky.edu

The effects of exercise have mainly been studied in vertebrates. Unfortunately, less work has focused on the varied group of organisms, invertebrates, which have more diverse collections of mechanisms to handle physiological problems associated with locomotion. Crayfish are freshwater crustaceans that reside mostly in water, exit for various reasons (i.e. food, mates, burrowing) and do gas exchange by pulling water over the gills. During periods of stress and physical exercise, crayfish exhibit typical fight or flight responses since they show a sympathetic-like response which appears to increase excitability to sustain physical activity. To meet the increase in oxygen demand due to exercise, a response in both cardiac (heart rate, HR) and respiratory (ventilation, VR) systems are required. Typically, both HR and VR increase in an effort to increase oxygen delivery to target tissues, especially muscles used for locomotion. Crayfish were exercised at normal walking speeds for two, fifteen minute periods. In addition, crayfish were exercised in two environments, aerated (normal) and nitrogen-saturated (oxygen-deficient). The purpose of this study is to examine the effect of intermittent periods of exercise in normal and low-oxygen environments on the HR and VR of crayfish since very few studies focus on the whole animal autonomic response. Preliminary results suggest increases in both HR/VR during the first and second periods of exercise. Crayfish returned close to baseline levels during the first recovery period in both environmental conditions, whereas VR levels remained elevated in the nitrogen-saturated environment during the second recovery period (after the second period of exercise).