The fast-growing Broiler chicken strain Ross 308 was used in this study. Fertile eggs were incubated in isobaric hypoxia (14 % O₂), while another group of eggs incubated in normoxia (21 % O₂) served as a control. The eggs were allowed to hatch in the same conditions they were incubated in, and after hatching the chickens from both groups were reared in normoxic conditions for 5 weeks.

The whole hearts of the embryos were sampled on the nineteenth day of incubation, and the left ventricles of the juveniles were sampled 35 days post hatching. These tissue samples were homogenized, and the protein extracts were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The separated proteins were then transferred by semi-dry electroblotting to polyvinylidene difluoride (PVDF) membranes, and probed using antibodies for inhibitory Gα proteins or stimulatory Gα proteins. The treated membranes were visualized using a charged couple device (CCD), and the relative amount of Gα proteins calculated as a percentage of an internal standard loaded with every experimental run.