The influences of parenterally administered dimethyl sulfoxide on regional blood flow

Regional blood flow studies utilizing the fractional distribution of ��Rb were conducted on rats. This procedure, introduced by Sapirstein (118, 119, 120), is based on the premise that certain substances, after a single intravenous injection, will be distributed initially to the organs in proportion to their blood flow. The intravenous study was conducted on 60 white rats. They were equally divided into control and DMSO-treated groups, each of which was subdivide into 6 groups of 5 rats. Each rat was anesthetized with sodium pentobarbital and received approximately 4.5 million dpm of ��Rb injection administered directly into the femoral vain. Five minutes prior to ��Rb injection, the members of the experimental group had 0.5 gms/kg of pure DMSO injected into the contralateral vein. Subsequent to ��Rb administration the animals of both groups were sacrificed at 2, 5, 10, 30, 60 and 300 seconds. Thirty additional rats were divided into 6 groups and topically subjected to several concentrations of DMSO for 30 minutes. Following a 30 second exposure to ��Rb the animals were sacrificed and the sartorius muscles underneath the site of DMSO application were removed and assayed. ..