Nerve conduction and ATP concentrations in sciatic-tibial and medial plantar nerves of hens given phenyl saligenin phosphate.
To assess the relationship of nerve conduction and adenosine triphosphate (ATP) status in organophosphorus-induced delayed neuropathy (OPIDN), we evaluated both in adult hen peripheral nerves following exposure to a single 2.5 mg/kg dose of phenyl saligenin phosphate (PSP). ATP concentrations were determined at days 2, 4, 7, and 14 post-dosing, from five segments (n = 5 per group) representing the entire length of the sciatic-tibial and medial plantar nerve. Initial effects of PSP dosing were seen in the most distal segment at day 2, when a transient ATP concentration increase (388 +/- 79 pmol/ml/mg versus control value of 215 +/- 23, P < 0.05) was noted. Subsequently, ATP concentration in this distal segment returned to normal. In the most proximal nerve segment, ATP concentrations were decreased on day 7, and further decreased on day 14 post-dosing (P < 0.05). Changes in ATP concentration and nerve conduction velocity begin at post-dosing day 2, and were found prior to development of clinical neuropathy and axonopathic lesions. These results suggest that alterations in sciatic-tibial and medial plantar nerve conduction associated with sciatic-tibial and medial plantar nerve ATP concentration are early events in the development of OPIDN.
Massicotte
C
C
Laboratory for Neurotoxicity Studies, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg 24061-0442, USA.
Barber
D S
DS
Jortner
B S
BS
Ehrich
M
M
D000200:Action Potentials / Q000187:drug effects; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002645:Chickens / Q000378:metabolism*; D004594:Electrophysiology; D005260:Female; D005528:Foot / Q000294:innervation*; D007306:Insecticides / Q000633:toxicity*; D009431:Neural Conduction / Q000187:drug effects*; D020258:Neurotoxicity Syndromes / Q000378:metabolism*; D009943:Organophosphorus Compounds / Q000633:toxicity*; D012584:Sciatic Nerve / Q000187:drug effects* / Q000378:metabolism*; D013979:Tibial Nerve / Q000187:drug effects* / Q000378:metabolism*; D013997:Time Factors
D007306:Insecticides; D009943:Organophosphorus Compounds; C046357:phenylsaligenin cyclic phosphate; D000255:Adenosine Triphosphate