Toxins latency period

Effects from exposure to toxins can appear within minutes or be delayed for days. The impacts from some toxins, especially cytotoxins, may occur within minutes but symptoms may not appear for hours. The route of exposure to the toxin can significantly change the latency period. 

Mouse Bioassay. When administered at 5 mg per mouse in 0.5 ml dose during the initial screening, the WSAP from G. toxicus caused death in all test mice within 120 minutes. The toxin had a latency period of approximately 30 minutes after which signs of toxicity were noticeable, and included in order of occurrance inactivity and piloerection followed by cyanosis of the tail and feet with concurrent hypothermia, vasodilation in the ears ( scarlet ears ), lacrimation, ptosis of the eye lid on the side of injection, ptosis of the abdomen (loss of muscular tone), asthenia, impairment of hind limb motor ability followed shortly by complete paralysis with the hind limbs extended posteriorly (complete prostration), and dyspnea (respiratory distress). Death occurred without convulsions and the eyes became cataracted just prior to or after death. 

Comparison of GT-3 and GT-4. Time dependent assays of the ether extracted GT-3 reported by Miller et al. (16) indicated that it had the same time course of action and irreversible effects as described for GT-4. When the ileal preparation was exposed to 10 ng/ml of GT-3 for 15 minutes a 50% inhibition from control response was observed. Upon contact with the preparation, the toxin caused a slow tonic contraction. Washing the segment with clean saline following the 15 minute exposure period caused a gradual relaxation of the preparation to near the base line levels observed in the control. However, when challenged by agonist at any time following the latency period, and irreversible loss of activity was evident. 

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