Endocrine effects of chronic administration of psychoactive drugs to prepubertal male rats. II. LSD.

The endocrine effects of chronic D-lysergic acid diethylamide (LSD) administration to prepubertal animals were studied by injecting intraperitoneally three times a week for a month either 100 mug or 500 mug of the psychoactive drug per kilogram or the vehicle to groups of Sprague-Dawley male rats starting at 21 days of age. Animals injected with either dosage of LSD had smaller body weights than controls and tail length was significantly reduced in the high dosage group, plasma levels of growth hormone (GH) were decreased in the high dosage group, and pituitary levels in the low dosage group. Plasma levels and pituitary concentrations of luteinizing hormone and follicle stimulating hormone were not significantly modified by the drug. The low dosage of LSD decreased the brain levels of noradrenaline and increased those of dopamine, while the high dosage decreased those of 5-hydroxyindoleacetic acid. These data suggest that LSD, when administered chronically to developing animals, can inhibit body growth probably by altering the secretion of GH through modifications of its neuroendocrine control.