“Pretreatment with phenoxybenzamine prevented the uptake of the guanidiniums by the spleen and, as a result, they were not subsequently released on nerve stimulation.”
“When phenoxybenzamine was added to the perfusate after administration of the guanidiniums , proportionately more norepinephrine was released than guanethidine or bethanidine, but a straight line relationship between the output of norepinephrine and the guanidiniums was still apparent.”