Effects of delta-aminolaevulinic acid administration on social behaviour in the laboratory mouse

Ethologic analysis has been used to study the behavioural effects following injection of delta-aminolaevulinic acid (ALA) in mice. After a dose level of 1.6 mmol ALA/kg, male and female mice showed periods of immobility and scanned less frequently than saline-injected controls. Exploration of the cage was significantly reduced in frequency in treated males, many elements of social and sexual investigation were reduced in treated females, and no elements of aggression were seen in treated males. Gait was abnormal and movement lethargic in animals showing the greatest degree of immobility. Righting reflexes and the response to stimuli of noise and touch remained normal. After a dose level of 0.8 mmol ALA/kg, no significant behavioural effects were detectable.