Increased circulating plasma volume following phenoxybenzamine (Dibenzyline)

Abstract

Dibenzyline (phenoxybenzamine hydrochloride; N-phenoxyisopropyl-N-benzyl-ß-chloroethylamine hydrochloride) produced a marked increase in the circulating plasma volume (T-1824) in the normothermic chick. It prevented most of the reduction in plasma volume which usually occurs during induced hypothermia. Calculated red cell mass was unaffected. Pentolinium and tetraethylammonium had no effects on either the plasma or cell volumes in normal or hypothermic chicks. Discriminatory sequestration of plasma and blood cells in different vascular beds is suggested, perhaps via neurogenic mechanisms.