Ontogeny of the behavioral effects of lysergic acid diethylamide in cats

In cats, the behavioral effects of LSD emerge around 21 days of age and reach adult levels by 35–40 days postpartum. Behaviors such as limb-flicking, abortive grooming, head-shakes, and investigatory responses appear at low frequency before 14 days, then increase rapidly. After an acute injection, effects last about 8 hours from their first appearance. Young kittens (21–42 days old) are resistant to developing tolerance with repeated doses. LSD can elicit behaviors like head-shakes and grooming earlier than they normally appear spontaneously, suggesting the neural and muscular systems for these behaviors develop before natural use.

Study at a glance

Abstract

AbstractThe ontogeny of the behavioral effects of lysergic acid diethylamide (LSD) was examined in cats between the ages of 4 and 112 days postpartum. The kittens showed little LSD‐induced behavioral change prior to 14 days of age. By the age of 21 days, however, the kittens exhibited many of the behavioral signs characteristic of LSD‐induced behaviors in adult cats. These behaviors include limbflicking, abortive grooming, head‐shakes, grooming, and investigatory responses. In general, these behaviors began at a low frequency of occurrence, then increased rapidly with advancing age, reaching adult values by approximately 35–40 days of age, and remained relatively constant through 112 days postpartum. The time course for the behavioral effects following an acute injection of LSD showed the adult pattern, i.e., persisting for approximately 8 hr post‐injection, from their earliest appearance during ontogeny. Young kittens (21–42 days of age) were resistant to the development of tolerance following repeated administration of the drug. LSD was capable of eliciting certain behaviors, such as head‐shakes and grooming, well in advance of the age at which they normally appear spontaneously. This indicates that the neuronal and musculature substrata are developed for the performance of these behaviors long before the kitten naturally employs them.