Meeting Abstract
Laboratories that research Drosophila melanogaster use carbon dioxide (CO2) on a daily basis to anesthetize flies for sorting and other work. However, CO2 has potential effects on a variety of physiological and behavioral mechanisms including respiratory and muscle physiology, and climbing and flight behavior. We have examined the effect of multiple levels of CO2 and varying exposure times on the subsequent recovery of motor function tested with both climbing and flight assays. We have found that with as little as five minutes exposure to 100% CO2 D. melanogaster exhibit motor deficits up to 16 hours after exposure. Any exposure length above five minutes produces behavioral effects on climbing that last for over 24 hours. Overall, there is a positive correlation between CO2 exposure length and recovery time. When given just one hour to recover after any length of exposure, climbing is reduced by 70-90% and flight by 40-60% as compared to control flies. This effect is not due to anoxia alone, but a CO2-specific mechanism as shown by a reduced impact of exposing D. melanogaster to just anoxia (100% nitrogen). Additionally, we have shown that exposure to as low as 65% CO2 (balanced with 20% oxygen and 15% nitrogen) affects the motor capability of D. melanogaster. Exposure of D. melanogaster to flow rates similar to that would be used in CO2-exposure pads in most laboratories reduces climbing ability by 35-75% depending on the flow rate. These results point to a strong impact of CO2 anesthesia on subsequent experimental tests in the lab indicating the importance of monitoring CO2 exposure levels, flow rate and length of exposure for any physiological or behavioral study.
