Lysergic acid diethylamide (LSD), 2,5-dimethoxy-4-methylamphetamine (DOM), mescaline, and the non-hallucinogenic LSD analogue lisuride were administered directly into the brain's lateral ventricle (intracerebroventricular, ICV) or injected into the abdomen (intraperitoneal, IP) of rats, and their effects on a fixed-ratio 40 operant behavior were compared. ICV administration of LSD, DOM, and mescaline disrupted behavior more potently than IP administration, with mescaline showing a 30-fold greater potency via ICV (ED50 74 micrograms) than IP (ED50 2251 micrograms). Lisuride showed no difference in potency between routes (ED50 4 micrograms both), suggesting its non-hallucinogenic effects are mediated differently.
A single dose of psilocybin given to female rats increased levels of multiple immune factors in the blood, including IL-1β, TNF-α, MCP-1, IP-10, G-CSF, IFN-γ, IL-10, IL-13, and leptin, after 24 hours, with further increases after seven days. Most other measured immune modulators showed similar but statistically non-significant increases. The findings indicate that psilocybin induces a generalized activation of the immune system that can persist for at least a week, which may relate to its therapeutic mechanism. Further research is needed to connect these immune effects to clinical outcomes in humans.