Subcutaneous and muscle blood flow during dopamine infusion in man

Abstract

Subcutaneous fat tissue and skeletal-muscle blood flow was measured in six male volunteers using the local ¹³³Xe-washout method. Measurements were obtained before and during intravenous dopamine infusion in non-pressor (1 μg kg^-1 min^-1) and pressor infusion rates (3-6 μg kg^-1 min^-1). During non-pressor infusion rate the systolic and diastolic arterial pressure and heart rate remained unchanged. When pressor dose dopamine was infused the systolic and mean arterial pressures increased significantly, whereas the diastolic pressure and the heart rate were left unchanged. The blood flow increased progressively from control values in both subcutis (control: 2.9±0.2, non-pressor: 5.0±1.6, pressor: 9.1±0.4 ml min^-1 100 g^-1, mean±SEM) and in skeletal muscle (control: 1.2±0.2, non-pressor: 1.510.2, pressor: 1.9±0.4ml min¹100g^-1,mean±SEM) and was significantly different from baseline values at any dopamine infusion rate. Side-effects were observed only at pressor dose infusion. It is concluded that dopamine in humans seems to possess vasodilatoric properties in subcutaneous fat tissue, and in skeletal muscles.

Key Words:

• dopamine receptors
• regulation of peripheral circulation
• tissue perfusion
• ¹³³Xe-washout method