Gangliosides minimize behavioral deficits and enhance structural repair after brain injury

Injections of GM1‐gangliosides (30 mg/kg, i. p.) in adult rats were shown to reduce behavioral deficits after brain lesions. This was observed (1) after bilateral electrolytic lesions of the caudate nucleus in a learning task involving negative reinforcement; (2) following aspiration lesions of the mediofrontal cortex in a learning task involving positive reinforcement; and (3) when rotational behavior was assessed after amphetamine or apomorphine injections in animals with partial hemitransections of the nigro‐striato‐nigral fibers. A detailed anatomical analysis of the latter study, using a retrograde tract‐tracing dye wheat germ agglutininhorseradish peroxidase (WGA‐HRP), provided evidence for ganglioside‐stimulated, neuronal reorganization of connections to the caudate nucleus. Our findings support the notion that gangliosides reduce behavioral deficits following brain injury by preventing secondary neuronal degeneration and/or enhancing structural reorganization of remaining afferents, rather than by influencing denervation supersensitivity.