Physiology & behavior
January 1, 1987
T Archer, E Arweström, B G Minor et al.
32 citations
In rats and mice, two drugs that activate serotonin receptors (8-OH-DPAT and 5-MeODMT) reliably produced pain relief in three different tests (tail-flick, hot-plate, and shock-titration). However, when the animals were pretreated with a toxin that destroys noradrenaline neurons (DSP4) given systemically, or with 6-hydroxydopamine injected directly into the spinal cord, the pain-relieving effects of both drugs were eliminated. In the tail-flick test, 8-OH-DPAT actually caused increased pain sensitivity after spinal cord noradrenaline depletion. Biochemical measurements confirmed that the toxins severely reduced noradrenaline in the spinal cord. The findings suggest that the pain relief from these serotonin drugs depends on intact noradrenaline nerve endings in the spinal cord, pointing to a critical interaction between noradrenaline and serotonin systems in spinal pain processing.
Physiology & behavior
May 3, 2011
David M Compton, Kerri L Dietrich, Melissa C Selinger et al.
21 citations
The recreational hallucinogen 5-MeO-DIPT (Foxy or Methoxy Foxy) impairs cognitive flexibility in rats when administered during adolescence. Rats given repeated injections of 5 or 20 mg/kg of the drug during one of two adolescent periods were later tested as adults on spatial memory and nonspatial tasks. Drug-treated rats performed as well as controls on spatial navigation to a fixed goal, but were markedly inferior when the goal moved to a new location and on a response learning task, indicating reduced ability to adapt to changing demands. The drug also reduced serotonin activity in the forebrain, similar to MDMA, suggesting it compromises serotonergic systems.
Physiology & behavior
October 1, 2024
Jasmine Shakir, Megan Pedicini, Brianna C Bullock et al.
5 citations
A single dose of psilocybin increased body weight in both male and female mice during the days immediately after treatment, without affecting how much they ate or drank. The weight gain was accompanied by increased lean and water mass in males, with a similar trend in females. Blocking the 5-HT2A/2C receptor with ketanserin did not prevent this effect. Blood tests showed elevated creatine kinase, aspartate aminotransferase, and chloride in treated mice. These results begin to clarify how psilocybin may influence body weight and metabolism, which is important for its safe use in clinical and non-clinical settings.
Physiology & behavior
September 1, 2025
Yiru Dong, Sebastian Goodwin-Groen, Jessie Ma et al.
4 citations
Repeated exposure to the activity-based anorexia (ABA) animal model, which mimics key features of anorexia nervosa such as starvation-induced hyperactivity and severe weight loss, can build resilience against relapse through synaptic changes. Sub-anesthetic ketamine given during mid-adolescence enhances this resilience. At medial prefrontal cortex synapses, ketamine increases GluN2B-containing NMDA receptors and the F-actin binding protein drebrin at excitatory synapses on pyramidal cells and GABA-interneurons. These molecular changes occur near 15 days post-injection during relapse in late adolescence. Ketamine treatment in late adolescence also reduces ABA relapse in adulthood, though less effectively. Wheel running promotes inhibitory GABAergic synapse formation on hippocampal pyramidal cells, and ketamine augments this inhibition, suppressing starvation-evoked hyperactivity and increasing food consumption and weight gain.