Pigs in which venous catheters were positioned for long-term use were injected i.v. with high doses of nicotine in physiol. saline. The LD50 was 2.656 mg/kg body weight. Clinical symptoms were mainly: forced respiration, muscular tremor to tetanoid spasms, cyanosis of the skin, salivation and sometimes vomiting. The degree and duration of symptoms were dose-dependent. Ecg changes in anaesthesized pigs following intravenous nicotine injections of 0.126 mg/kg and 0.378 mg/kg at 15 minutes' interval were immediately commencing disturbances of the heart rate in form of bradycardia and asystolia. After 5 sec we observed extrasystoles, tachycardia, sino-auricular block and AV-block of first and second degree as well as a number of T- and P-changes. Changes of the ecg were observed generally for 10 to 15 min, however, the T-wave remained sometimes negative or biphasic-preterminal negative for some hours.

Animals↗

PubMedDate not supplied

[Effect of nicotine in pigs (author's transl)].

18 pigs in which venous catheters were positioned for long-term use were injected with nicotine in physiological saline: group 1: 1 mg without anaesthesia; group 2: 1 mg/animal, Hypnodil-anaesthesia; group 3: 0.0143 mg/kg body weight, Hypnodil-anaesthesia. The dose of 1 mg is corresponding to that amount of nicotine contained in the main smoke of a commercially used cigarette. The dose of 0.143 mg/kg body weight is calculated per 1 kg body weight assuming that a man of 70 kg body weight resorbes the total amount of nicotine (1 mg) after maximum inhalation. Application of 1 mg induced the following alterations: sino-auricular block, AV-block of first and second degree, asystolia up to 2 seconds, short decrease in blood pressure and bradycardia as well as flattening and/or inversion and biphasic reaction of T. A longer lasting increase in blood pressure was observed in non-anaesthesized animals. Animals treated with 0.0143 mg/kg body weight showed AV-block of first degree with subsequent extrasystoles. Blood pressure, heart rate and T-wave showed no alterations. Decisive for the induction and extent of acute disturbances seems to be the dose of nicotine. Therefore, a decrease of the nicotine content seems to be indicated toward a "less harmful cigarette".

Animals↗