Embryotoxicity of solanine and aspirin in mice

Anencephaly occurs more frequently in Ireland than in most other parts of the world (Coffey & Jessop, 1957; Elwood & Warnock, 1969), and the observed seasonal variation in incidence (Edwards, 1958; Leck, 1966; Elwood & MacKenzie, 1971) suggests that environmental factors may be of some importance. Renwick (1972) proposed that this malformation might be associated with maternal exposure to a potato teratogen ofunspecified nature. The teratogen appeared to be more concentrated in certain varieties of potato, particularly in overwintered tubers that are partly blighted or injured. Solanine is an alkaloid found in greater concentration in potatoes which have been exposed to light (Liljemark & Widoff, 1960), stored for long periods or injured (Gull & Isenberg, 1960), and there are varietal differences in solanine levels (Liljemark & Widoff, 1960). Gastrointestinal illness in man has been associated with ingestion of potatoes containing 25 mg solanine/kg (Wilson, 1959), and has also been shown to be toxic to mice, rats and rabbits when administered parenterally (Nishie, Gumbmann & Keyl, 1971). This study was therefore designed to investigate the effects of solanine on pregnancy in mice when given alone, and also in combination with aspirin because aspirin ingestion is one of the commonest forms of self-medication, and may have a potentiating effect. Adult ASH/CS1 mice weighing 24\m=.\05 \m=+-\ 6 (S.D.) g were allowed free access to food and water. Females were paired monogamously with males for 4 nights and then randomly allocated to one of 9 groups (Table 1 ). The first night of pairing was designated as Day 1. All substances were given intraperitoneally; the saline (0\m=.\9%) in a volume equivalent to that of the treated animals, i.e. about 1 ml/mouse. Commercially extracted solanine (Aldrich Chemical Co., Inc., Milwaukee, U.S.A.) was prepared in a saline solution in a concentration of 0\m=.\5 mg/ml. The dosage of soluble aspirin (B.P.; 10 mg/ml) was 20% lower than that for the LD50 given by Barnes & Eltherington (1964). All the mice were killed on Day 17 and the numbers of live and resorbing fetuses were determined. The results are shown in Table 1.