Leucine as an in vitro precursor to lipids in rat sciatic nerve

Lipids ◽  
1979 ◽  
Vol 14 (2) ◽  
pp. 127-131 ◽  
Author(s):  
Lewis W. Stillway ◽  
Dorothy A. Weigand ◽  
Maria G. Buse
Keyword(s):  
Sciatic Nerve ◽  
Rat Sciatic Nerve

scholarly journals E8002 Inhibits Peripheral Nerve Adhesion by Enhancing Fibrinolysis of l-Ascorbic Acid in a Rat Sciatic Nerve Model

2020 ◽  
Vol 21 (11) ◽  
pp. 3972
Author(s):  
Kiyoshi Kikuchi ◽  
Kentaro Setoyama ◽  
Seiya Takada ◽  
Shotaro Otsuka ◽  
Kazuki Nakanishi ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Sciatic Nerve ◽  
Peripheral Nerve ◽  
In Vitro Study ◽  
Scar Tissue ◽  
Tissue Type ◽  
Rat Sciatic Nerve ◽  
Peripheral Nerve Surgery ◽  
Nerve Surgery

Perineural adhesions leading to neuropathy are one of the most undesirable consequences of peripheral nerve surgery. However, there are currently no widely used compounds with anti-adhesive effects in the field of peripheral nerve surgery. E8002 is a novel, anti-adhesive, multi-layer membrane that contains L-ascorbic acid (AA). Here, we investigated the effect and mechanism of E8002 in a rat sciatic nerve adhesion model. A total of 21 rats were used. Six weeks after surgery, macroscopic adhesion scores were significantly lower in the E8002 group (adhesion procedure followed by nerve wrapping with E8002) compared to the E8002 AA(−) group (adhesion procedure followed by nerve wrapping with the E8002 membrane excluding AA) and adhesion group (adhesion procedure but no treatment). Correspondingly, a microscopic examination revealed prominent scar tissue in the E8002 AA(−) and adhesion groups. Furthermore, an in vitro study using human blood samples showed that AA enhanced tissue-type, plasminogen activator-mediated fibrinolysis. Altogether, these results suggest that E8002 may exert an anti-adhesive action via AA and the regulation of fibrinolysis.

N -Phenylethyl Amitriptyline in Rat Sciatic Nerve Blockade

2002 ◽  
Vol 96 (6) ◽  
pp. 1435-1442 ◽  
Author(s):  
Peter Gerner ◽  
Mustafa Mujtaba ◽  
Mohammed Khan ◽  
Yukari Sudoh ◽  
Kamen Vlassakov ◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Sciatic Nerve ◽  
Therapeutic Range ◽  
Local Anesthetic ◽  
Na Channel ◽  
Patch Clamp Technique ◽  
Rat Sciatic Nerve ◽  
Nerve Model

Background The antidepressant amitriptyline is commonly used orally for the treatment of chronic pain, particularly neuropathic pain, which is thought to be caused by high-frequency ectopic discharge. Among its many properties, amitriptyline is a potent Na(+) channel blocker in vitro, has local anesthetic properties in vivo, and confers additional blockade at high stimulus-discharge rates (use-dependent blockade). As with other drug modifications, adding a phenylethyl group to obtain a permanently charged quaternary ammonium derivative may improve these advantageous properties. Methods The electrophysiologic properties of N-phenylethyl amitriptyline were assessed in cultured neuronal GH(3) cells with the whole cell mode of the patch clamp technique, and the therapeutic range and toxicity were evaluated in the rat sciatic nerve model. Results In vitro, N-phenylethyl amitriptyline at 10 microm elicits a greater block of Na(+) channels than amitriptyline (resting block of approximately 90% vs. approximately 15%). This derivative also retains the attribute of amitriptyline in evoking high-degree use-dependent blockade during repetitive pulses. In vivo, duration to full recovery of nociception in the sciatic nerve model was 1,932 +/- 72 min for N-phenylethyl amitriptyline at 2.5 mm (n = 7) versus 72 +/- 3 min for lidocaine at 37 mm (n = 4; mean +/- SEM). However, there was evidence of neurotoxicity at 5 mm. Conclusion N-phenylethyl amitriptyline appears to have a narrow therapeutic range but is much more potent than lidocaine, providing a block duration several times longer than any clinically used local anesthetic. Further work in animal models of neuropathic pain will assess the potential use of this drug.

ESSENTIAL OIL OF CROTON NEPETAEFOLIUS AND ITS MAIN CONSTITUENT, 1,8-CINEOLE, BLOCK EXCITABILITY OF RAT SCIATIC NERVE IN VITRO

2006 ◽  
Vol 33 (12) ◽  
pp. 1158-1163 ◽  
Author(s):  
PM Lima-Accioly ◽  
PR Lavor-Porto ◽  
FS Cavalcante ◽  
PJC Magalhães ◽  
S Lahlou ◽  
...  
Keyword(s):  
Sciatic Nerve ◽  
Essential Oil ◽  
Main Constituent ◽  
Rat Sciatic Nerve

scholarly journals Effects of collagen membranes enriched with in vitro-differentiated N1E-115 cells on rat sciatic nerve regeneration after end-to-end repair

2010 ◽  
Vol 7 (1) ◽  
pp. 7 ◽  
Author(s):  
Sandra Amado ◽  
Jorge M Rodrigues ◽  
Ana L Luís ◽  
Paulo AS Armada-da-Silva ◽  
Márcia Vieira ◽  
...  
Keyword(s):  
Sciatic Nerve ◽  
Nerve Regeneration ◽  
Rat Sciatic Nerve ◽  
End To End ◽  
Collagen Membranes ◽  
Sciatic Nerve Regeneration

Ischemic neurophysiological changes of rat sciatic nerve in vitro

2002 ◽  
Vol 9 (1) ◽  
pp. 7-11 ◽  
Author(s):  
Mitsuaki Shioyama ◽  
Mikihiro Kihara ◽  
Mitsuo Takahashi
Keyword(s):  
Sciatic Nerve ◽  
Rat Sciatic Nerve

scholarly journals Functional and Physical Outcomes following Use of a Flexible CO2Laser Fiber and Bipolar Electrocautery in Close Proximity to the Rat Sciatic Nerve with Correlation to an In Vitro Thermal Profile Model

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
A. M. Robinson ◽  
A. J. Fishman ◽  
B. R. Bendok ◽  
C.-P. Richter
Keyword(s):  
Sciatic Nerve ◽  
Nerve Damage ◽  
Heating Zone ◽  
Physical Damage ◽  
Rat Sciatic Nerve ◽  
Close Proximity ◽  
Minimal Damage ◽  
Vitro Model ◽  
Heating Profiles

This study compared functional and physical collateral damage to a nerve when operating a Codman MALIS Bipolar Electrosurgical System CMC-III or a CO2laser coupled to a laser, with correlation to an in vitro model of heating profiles created by the devices in thermochromic ink agarose. Functional damage of the rat sciatic nerve after operating the MALIS or CO2laser at various power settings and proximities to the nerve was measured by electrically evoked nerve action potentials, and histology of the nerve was used to assess physical damage. Thermochromic ink dissolved in agarose was used to model the spatial and temporal profile of the collateral heating zone of the electrosurgical system and the laser ablation cone. We found that this laser can be operated at 2 W directly above the nerve with minimal damage, while power settings of 5 W and 10 W resulted in acute functional and physical nerve damage, correlating with the maximal heating cone in the thermochromic ink model. MALIS settings up to 40 (11 W) did not result in major functional or physical nerve damage until the nerve was between the forceps tips, correlating with the hottest zone, localized discretely between the tips.

Potency of Bupivacaine Stereoisomers Tested  In Vitro and  In Vivo

2000 ◽  
Vol 93 (3) ◽  
pp. 744-755 ◽  
Author(s):  
Marina Vladimirov ◽  
Carla Nau ◽  
Wai Man Mok ◽  
Gary Strichartz
Keyword(s):  
Sciatic Nerve ◽  
Nerve Block ◽  
Local Anesthetics ◽  
Neuroendocrine Cells ◽  
Primary Role ◽  
Na Channels ◽  
Rat Sciatic Nerve ◽  
Na Currents

Background Chiral local anesthetics, such as ropivacaine and levobupivacaine, have the potential advantage over racemic mixtures in showing reduced toxic side effects. However, these S-(levo, or "-")isomers also have reportedly lower potency than their optical antipode, possibly resulting in no advantage in therapeutic index. Potency for local anesthetics inhibiting Na+ channels or action potentials depends on the pattern of membrane potential and so also does the stereopotency ratio. Here the authors have quantitated the stereopotencies of R-, S-, and racemic bupivacaine, comparing several in vitro assays of neuronal Na+ channels with those from in vivo functional nerve block, to establish relative potencies and to understand better the role of different modes of channel inhibition in overall functional anesthesia. Methods The binding of bupivacaine to Na+ channels was assessed indirectly by its antagonism of [3H]-batrachotoxin binding to rat brain synaptosomes. Inhibition of Na+ currents by bupivacaine was directly assayed in voltage-clamped GH-3 neuroendocrine cells. Neurobehavioral functions were disrupted by bupivacaine percutaneously injected (0.1 ml; 0.0625-1.0%) at the rat sciatic nerve and semiquantitatively assayed. Concentration-dependent actions of R-, S-, and racemic bupivacaine were compared for their magnitude and duration of action. Results Competitive batrachotoxin displacement has a stereopotency ratio of R:S = 3:1. Inhibition of Na+ currents with different prepulse potentials shows that S > R potency when the membrane is hyperpolarized, and R > S potency when it is depolarized from normal resting values. Functional deficits assayed in vivo usually demonstrate no consistent enantioselectivity and only a modest stereopotency (R:S = 1.2-1.3) for peak analgesia achieved at the lowest doses. Other functions display no significant stereopotency in either the degree, the duration, or their product (area under the curve) at any dose. Conclusion Although the in vitro actions of bupivacaine showed stereoselectivity ratios of 1.3-3:1 (R:S), in vivo nerve block at clinically used concentrations showed much smaller ratios for peak effect and no significant enantioselectivity for duration. A primary role for the blockade of resting rather than open or inactivated Na+ channels may explain the modest stereoselectivity in vivo, although stereoselective factors controlling local disposition cannot be ruled out. Levo-(S-)bupivacaine is effectively equipotent to R- or racemic bupivacaine in vivo for rat sciatic nerve block.

Sign in / Sign up

Export Citation Format

Share Document