Effects of 4-Aminopyridine on Saxitoxin Intoxication

Abstract

Effects of 4-aminopyridine (4-AP) on neurotoxicity induced by saxitoxin (STX) are investigated in this study. In vitro, twitch tension evoked by nerve stimulation was depressed by STX (1.35 nM) in rat phrenic nerve-diaphragm preparations, and this inhibition was antagonized by 4-AP (0.1 mM). In addition, 4-AP (0.1 mM) restored the firing of membrane action potentials that were suppressed or even abolished by 0.334 nM STX in frog sartorius muscles. In vivo studies showed that 4-AP (0.3 mg/kg, iv) significantly reversed the respiratory rate, tidal volume, and blood pressure to normal values in anesthetized STX-toxicosis rats. Furthermore, 4-AP (0.75-6 mg/kg, ip) not only prolonged the survival time but also decreased the mortality of mice (71-43%) at a normally lethal dose (30 micrograms/kg, ip) of STX. The results suggest that 4-AP may be useful as an antidote for STX intoxication.

Tetrodotoxin: Chemistry, Toxicity, Source, Distribution and Detection

“…Several treatments for TTX poisoning have been discussed earlier in the text ( Section 7.6 ). Interestingly, 4-aminopyridine was observed to reverse the effect of saxitoxin and tetrodotoxin in mice without any side effects such as seizure or convulsions [ 231 , 232 ]. The optimal 4-AP dose was determined as 2 mg/kg (im) [ 232 ].…”

Quantitation of Saxitoxin in Human Urine Using Immunocapture Extraction and LC–MS

“…While PSPs can be lethal due to respiratory failure, the symptoms are generally mild and include paralysis, gastrointestinal issues, muscle weakness, and tingling or numbness of the mouth and extremities. Other than supportive care, few treatments are available for PSP [5][6][7]. The direct testing of patient samples for STX is the only way to truly confirm PSP toxin exposure, while also helping to avoid misdiagnosis of paralysis due to conditions with similar symptomology [8].…”

Adverse stimulation of 4-nonylphenol in abnormal reproductive organs of female chickens

“…Similar to other effective non-ionic surfactant, NP carries properties that induce endocrine disruption, consequently interfering with various hormonal physiological functions. Numerous reports have suggested that NP might have adverse effects on the reproductive function [ 11 , 12 , 13 , 14 , 15 ]. In male offspring, a slower maturation of the gonadotrophic system is caused by chronic exposure to NP [ 16 , 17 , 18 ].…”