Abstract
The pharmacological actions of BB-K8, a new semisynthetic aminoglycoside antibiotic in which 1-NH of kanamycin was replaced with 4-amino-2-hydroxybutyric acid, were investigated.
Summary of pharmacological actions and minimal effective doses (MED) of BB-K 8 were as follows: fall on blood pressure of the rabbit (20mg/kg), bradycardia on ECG of the rabbit (50mg/kg), inhibition on excised guinea-pig atrium (2×10-4g/ml), inhibition on excised frog heart (10-8g/ml), acceleration on permeability of rabbit abdominal skin vessels (100mcg), stimulation (2×10-4g/ml) and inhibition (5×10-4g/ml) on excised rabbit intestine, inhibition on excised tracheal muscle of the guinea-pig (10-8 g/ml) and inhibition on excised rat uterus (5×10-4g/ml for nonpregnant uterus and 10-4g/ml for pregnant uterus). No effect on respiration of the rabbit, on excised rabbit ear vessels or on excised guinea-pig intestine was observed at doses up to 80mg/kg, 10-1g/ml and 2×10-8g/ml, respectively.
Its actions were similar to other aminoglycoside antibiotics and MED were larger in general. These MED also were much larger than minimum inhibitory concentrations and maximum blood levels in clinical uses. Therefore, it is concluded that BB-K8 is one of the antibiotics with less pharmacological actions.
