Pharmacodynamics and Pharmacokinetics of Lidocaine in a Rodent Model of Diabetic Neuropathy.

Anesthesiology

From the Department of Anesthesiology and Laboratory of Experimental Anesthesiology and Intensive Care (LEICA) (W.t.H., M.W.H., J.H., S.P., P.L.); Department of Nuclear Medicine (K.d.B., H.J.V.), Cardiology (A.O.V., H.L.T.), Anatomy, Embryology and Physiology (A.O.V.), and Neurology (C.V.), Academic Medical Center University of Amsterdam, Amsterdam, The Netherlands; Department of Anesthesiology and Intensive Care Medicine, Trauma Hospital, Graz, Austria (M.R.); Department of Anesthesiology, University of Heidelberg, Heidelberg, Germany (S.P.) and Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts (P.L.).

Published: March 2018

Background: Clinical and experimental data show that peripheral nerve blocks last longer in the presence of diabetic neuropathy. This may occur because diabetic nerve fibers are more sensitive to local anesthetics or because the local anesthetic concentration decreases more slowly in the diabetic nerve. The aim of this study was to investigate both hypotheses in a rodent model of neuropathy secondary to type 2 diabetes.

Methods: We performed a series of sciatic nerve block experiments in 25 Zucker Diabetic Fatty rats aged 20 weeks with a neuropathy component confirmed by neurophysiology and control rats. We determined in vivo the minimum local anesthetic dose of lidocaine for sciatic nerve block. To investigate the pharmacokinetic hypothesis, we determined concentrations of radiolabeled (C) lidocaine up to 90 min after administration. Last, dorsal root ganglia were excised for patch clamp measurements of sodium channel activity.

Results: First, in vivo minimum local anesthetic dose of lidocaine for sciatic nerve motor block was significantly lower in diabetic (0.9%) as compared to control rats (1.4%). Second, at 60 min after nerve block, intraneural lidocaine was higher in the diabetic animals. Third, single cell measurements showed a lower inhibitory concentration of lidocaine for blocking sodium currents in neuropathic as compared to control neurons.

Conclusions: We demonstrate increased sensitivity of the diabetic neuropathic nerve toward local anesthetics, and prolonged residence time of local anesthetics in the diabetic neuropathic nerve. In this rodent model of neuropathy, both pharmacodynamic and pharmacokinetic mechanisms contribute to prolonged nerve block duration.

Download full-text PDF

Source
http://dx.doi.org/10.1097/ALN.0000000000002035DOI Listing

Publication Analysis

Top Keywords

nerve block
16
rodent model
12
local anesthetics
12
local anesthetic
12
sciatic nerve
12
nerve
10
diabetic
9
diabetic neuropathy
8
diabetic nerve
8
model neuropathy
8

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!