Chronic toxicity study of neosaxitoxin in rats.

Marine drugs (2014-09-27)
Ramiro J Zepeda, Manila Candiracci, Nicolas Lobos, Sebastian Lux, Hugo F Miranda

Neosaxitoxin (NeoSTX) is a specific reversible blocker of voltage gated sodium channels on excitable cells. In the last decade, it has been tested in a number of interesting clinical trials, however there is still little information available on mammalian toxicity. Rats were treated for 12 weeks with doses of 1, 3 or 6 μg/kg of subcutaneous NeoSTX. At weeks 12 and 17, animals were sacrificed and blood samples collected for hematological and biochemical analysis. Organs were harvested for weight determination and histopathological assessments. The lowest acute toxicity via the intraperitoneal (ip) route was (30.35 μg/kg) and there was no significant difference between intramuscular and subcutaneous routes (11.4 and 12.41 μg/kg). The NeoSTX adiministration did not produce lethality at week 12 and after five weeks of suspension. NeoSTX 6 μg/kg ip produced reductions (p < 0.05) in body weight and food intake, and increased blood level of total and direct bilirubin, GGT and SGOT at week 12; all of these were reversed in the recovery period. NeoSTX 1 and 3 μg/kg ip did not show significant changes with the control group. Histopathological presentations were normal in all groups. This study revealed that NeoSTX is safe in vivo, giving a reliable security margin for its use like a local anesthetic.

Product Number
Product Description

Nitric-14N acid solution, ~10 N in H2O, 99.99 atom % 14N
Nitric acid, 70%, purified by redistillation, ≥99.999% trace metals basis
Nitric acid concentrate, 0.1 M HNO3 in water (0.1N), eluent concentrate for IC
Nitric acid, ACS reagent, ≥90.0%
Nitric acid, red, fuming, HNO3 >90 %
Nitric acid, puriss. p.a., ≥65% (T)
Nitric acid, puriss. p.a., 65.0-67.0%
Nitric acid, puriss. p.a., reag. ISO, reag. Ph. Eur., for determinations with dithizone, ≥65%
Nitric acid, ACS reagent, 70%