Variation of rat serum biochemical values following decapitation or anesthesia with ether, halothane or Innovar-VetR: rapid Innovar-VetR-induced hyperuricemia and hyperglycemia.

True reference values (TRV) should ultimately be determined in blood from inactive, unstimulated rats but in practice, acceptable reference values (ARV) may be established using blood from decapitated or anesthetized animals if one is cognizant of variations associated with blood sampling procedures. Data reported here illustrate some variations in serum biochemical values following decapitation or anesthesia. Decapitation does not provide serum in which ARV for sodium, potassium or lactate dehydrogenase can be found but ARV can be determined for glucose, insulin and several other parameters. It is suggested that both TRV and ARV for serum electrolytes be determined using serum from cannulated rats. All three anesthetics raised glucose levels and ether and halothane increased alkaline phosphatase activity. Both halothane and Innovar-VetR decreased insulin:glucose ratios suggesting inhibition of insulin release from the pancreas. Innovar-VetR also produced hypoxia due to severe respiratory depression and bradycardia as well as hyperuricemia, hyperglycemia and hyperphosphatemia. Techniques most likely to provide ARV should be of the shortest possible duration, afford least respiratory and cardiovascular suppression and minimize stimulation of the sympathetic nervous system.