Measurement of Regional Blood Flow in the Golden Hamster 1

Abstract

The cheek pouch of the golden hamster (Mesocricatus auratus) has been used extensively in both microcirculatory studies and tissue transplant experimentation (cf. 1). Data on the blood flow to various tissues and particularly the cheek pouch and cremaster muscle would be valuable in the interpretation of many types of experiments, but these data are not available. The purpose of this study was to obtain relative blood flow measurements in the hamster. In addition, we have measured the cardiac output by a simplified indicator dilution method.

Methods. Animals were 90–120 g, male golden hamsters obtained from Chickline Animal Supply. Five hamsters were anesthetized with 60 mg/kg pentobarbital, ip. Rectal temperature was measured with a Yellow Springs Instruments telethermometer and was maintained at 38° with an external heat lamp. A carotid artery and femoral vein were cannulated with polyethylene tubing and the cannulae were passed into the aorta and inferior vena cava, respectively.

Regional blood flows, as fraction of total cardiac output, were measured with the Sapirstein cardiac-output fractionation technique using ⁸⁶Rb as the indicator (2). At zero time, 0.1 ml of isotonic ⁸⁶Rb (10 μCi/ml) was injected into the femoral cannula and at 45 sec the animal was killed with 1 ml of 3 M KC1 injected into the femoral venous cannula.

Tissue samples were obtained from the cheek pouch, cremaster, gastrocnemius muscle, ventricles and diaphragm and were weighed and digested in 0.5–1.0 ml of nitric acid at 80°. Arterial blood samples were hemolyzed with distilled water. All samples were diluted to a final volume of 2 ml with distilled water before counting. ⁸⁶Rb activity was determined in a Baird-Atomic well scintillation counter. Fractions of cardiac output per gram wet weight of tissue were calculated from the ratios of counts per gram in tissue to total counts injected.