Madagascar Hissing Cockroach hemolymph PO2, PCO2, and gas exchange parameters

This data set contains in vivo measurements of hemolymph PO2 and PCO2 made on Madagascar hissing cockroaches (Gromphadorhina portentosa) using implanted micro fiber optic sensors (optodes). In addition, rate of CO2 release, ventilation frequency, and durations of the tri-phasic discontinuous gas exchange cycle associated with these measurements are also recorded. All measurements were performed while the cockroaches were breathing either normoxic and normocapnic air, hypoxic air (10 kPa PO2), or hypercapnic air (2 kPa PCO2) at 22 ºC.

Methods
These data were collected and analyzed according to the materials and methods in the associated JEB article. Briefly, Madagascar hissing cockroaches (Gromphadorhina portentosa) were secured in a respirometry chamber with PCO2 and PO2 optodes implanted in their hemocoel. A reflection sensor beneath their abdomen recorded abdominal pumping movements. Cockroaches were exposed to normoxic normocapnia, hypoxic normocapnia, and normoxic hypercapnia. Roaches were exposed to these gas mixtures while intact and breathing continuously, and then decapitated which induced discontinuous gas exchange cycles (DGCs), before being exposed to the same gas mixtures as before. During these exposures, hemolymph PO2, PCO2, VCO2, and abdominal movements were recorded continuously. The summary data extracted form these data traces are presented here.