The effect of 6-hydroxydopamine-induced hepatic sympathectomy on the early hyperglycemic response to surgical trauma under anesthesia.

A single intraportal injection of 6-OH-DA (50mg/kg) in rats results in a functional hepatic sympathectomy 6 days following the injection. Laparotomy and mild abdominal exploration under pentobarbital anesthesia resulted in elevated plasma glucose levels within 15 minutes as a result of activation of the sympathetic nerves to the liver and adrenal gland discharge. The hyperglycemic response to trauma was reduced by fasting. The hyperglycemic response was examined in untreated rats, 6-OH-DA pretreated rats, bilaterally adrenalectomized rats, and a group which had received 6-OH-DA pretreatment as well as bilateral adrenalectomy. In non-fasted rats the presence of intact sympathetic nerves or intact adrenals was sufficient to produce the hyperglycemia. To prevent the response both nerves and adrenals must be deactivated. The hepatic nerves are primarily responsible for the early hyperglycemic response to trauma in fasted rats while in fed animals the adrenals and hepatic nerves play a more equal role.