Role of glucocorticoids in an abnormal grooming behavior in cats with pontile or frontal neocortical lesions.

Cats with pontile or frontal neocortical lesions display a tactually elicited dissociation of appetitive and consummatory grooming behaviors. Systemic administration of glucocorticoids abolished the abnormal grooming behavior in cats with lesions, even when the stimulatory effect of glucocorticoids on serotonin metabolism was blocked by administration of p-chlorophenylalanine (PCPA). Microinjections of glucocorticoids into the superior colliculi also significantly decreased the abnormal grooming behavior. Adrenalectomized cats did not display the abnormal grooming behavior, but the abnormal behavior did occur in PCPA-treated adrenalectomized cats. Administration of either glucorticoids or 5-hydroxytryptophan abolished the abnormal behavior in PCPA-treated adrenalectomized cats. Thus, it appears that the pontile and frontal neocortical lesions produce deficits in both glucocorticoids and serotonin, and these deficits are necessary and sufficient conditions for inducing the abnormal grooming behavior.