Dopamine beta-hydroxylase inhibition reveals a selective influence of endotoxin on catecholamine content of rat tissues.

Endotoxin is known to affect sympathetic nervous system (SNS) activity. However, it is unknown whether selective activation occurs in different tissues. The present work assessed SNS activity in several tissues of endotoxin-treated rats by measuring the accumulation of dopamine following dopamine beta-hydroxylase inhibition with disulfiram. Twenty-four hours following endotoxin injection (1 mg/kg), body weight and food intake were significantly reduced. The weight of spleen and liver was significantly greater in endotoxin-injected rats compared to either control animals or rats pair-fed the same quantity of food ingested by the endotoxin-treated rats. Norepinephrine (NE) content of heart, liver, and brown adipose tissue (BAT) was significantly lower in endotoxin-injected animals, but it was unchanged in spleen and gastrocnemius muscle. Endotoxin caused a significant elevation in the dopamine content of heart, liver, BAT, and gastrocnemius muscle, whereas it had no effect on spleen. The results suggest that SNS activity is increased in heart, liver, BAT, and gastrocnemius muscle 26 h after endotoxin injection.