To determine the suitability of halothane anesthesia for studies of sympathetic control of the endocrine pancreas in dogs, we assessed the effect of halothane anesthesia (0.8% inspired concentration) on the sympathetic response to central neuroglucopenia. In dogs anesthetized with halothane, intravenous administration of the neuroglucopenic agent, 2-deoxy-d-glucose (2-DG; 100 mg/kg), produced increases of both systemic plasma epinephrine (EPI; Δ = 269 ± 86 pg/ml, P < 0.025) and norepinephrine (NE; Δ = 157 ± 55 pg/ml, P < 0.025) equivalent to those previously observed in conscious dogs. Measurement of plasma NE kinetics revealed that the plasma NE response to 2-DG during halothane was due to an increase in the rate of NE appearance that was identical to that of conscious dogs, rather than to an impairment of NE clearance. In contrast, 2-DG at this dose did not increase plasma EPI or NE levels in dogs anesthetized with pentobarbital sodium (30 mg/kg). Plasma glucose increased modestly after 2-DG (100 mg/kg) in both conscious and halothane-anesthetized dogs but not in the pentobarbital-anesthetized dogs. Although 2-DG at a threefold higher dose (300 mg/kg) caused plasma EPI, NE, and glucose (Δ = 12 ± 3 mg/dl, P < 0.001) to increase in pentobarbital-anesthetized dogs, the responses to this higher dose of 2-DG were all significantly larger in halothane-anesthetized dogs (Δ of plasma glucose = 30 ± 8 mg/dl, P < 0.005; P < 0.0025 vs. pentobarbital). The catecholamine data demonstrate that halothane is a more suitable anesthetic than pentobarbital for use in experiments studying reflex neuroglucopenic activation of the sympathetic nervous system. The glucose data suggest that certain metabolic responses secondary to sympathetic activation are also preserved in halothane-anesthetized animals.
|Original language||English (US)|
|Journal||American Journal of Physiology - Endocrinology and Metabolism|
|State||Published - 1987|
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