Synapse (New York, N.Y.)
November 1, 2025
Oliver H Miller, Nils Grabole, Isabelle Wells et al.
Low-dose ketamine is an efficacious antidepressant for treatment-resistant unipolar and bipolar depressed patients. Major depressive disorder patients receiving a single infusion report elevated mood within 2 h, and ketamine's antidepressant effects have been observed as long as 7 days posttreatment. In light of this remarkable observation, efforts have been undertaken to "reverse-translate"...
Synapse (New York, N.Y.)
March 1, 2025
Yang Wang, Jesper L. Kristensen, Kristi A. Kohlmeier
5 citations
Psychedelic compounds have gained renewed interest due to their rapid and long-lasting therapeutic effects on stress-related disorders. While the underlying mechanisms of therapeutic actions of psychedelic compounds are still unclear, these drugs are thought to modulate the activity of the serotonergic system, primarily through activating serotonin type 2A receptor (5-HT2AR) and studies have...
Synapse (New York, N.Y.)
2025
Yiru Dong, Chiye Aoki
2 citations
Anorexia nervosa (AN) is an eating disorder with the second highest mortality of all mental illnesses and high relapse rate, especially among adult females, yet with no accepted pharmacotherapy. A small number of studies have reported that adult females who struggled with severe and relapsing AN experienced sustained remission of the illness following ketamine infusions. Two other reports...
Synapse (New York, N.Y.)
July 1, 2024
Simone Larsen Bærentzen, Jakob Borup Thomsen, Majken Borup Thomsen et al.
1 citation
Major depressive disorder is one of the most prevalent mental health disorders, posing a global socioeconomic burden. Conventional antidepressant treatments have a slow onset of action, and 30% of patients show no clinically significant treatment response. The recently approved fast-acting antidepressant S-ketamine, an N-methyl-D-aspartate receptor antagonist, provides a new approach for...
Synapse (New York, N.Y.)
October 2011
Melanie Mueller, Jie Yuan, Concepcion Maldonado Adrian et al.
3,4-Methylenedioxymethamphetamine (MDMA)'s O-demethylenated metabolite, 3,4-dihydroxymethamphetamine (HHMA), has been hypothesized to serve as a precursor for the formation of toxic catechol-thioether metabolites (e.g., 5-N-acetylcystein-S-yl-HHMA) that mediate MDMA neurotoxicity. To further test this hypothesis, HHMA formation was blocked with dextromethorphan (DXM), which competitively...
Synapse (New York, N.Y.)
February 2011
Sherry M Zakhary, Diana Ayubcha, Farah Ansari et al.
Ketamine exerts powerful anesthetic, psychotic, and antidepressant effects in both healthy volunteers and clinically depressed patients. Although ketamine targets particular glutamate receptors, there is a dearth of evidence for additional, alternative molecular substrates for the behavioral actions of this N-methyl-D-aspartate (NMDA) receptor antagonist drug. Here, we provide behavioral and...
Synapse (New York, N.Y.)
August 1, 2009
Philip Seeman, Hong-Chang Guan, Hélène Hirbec
83 citations
Although it is commonly stated that phencyclidine is an antagonist at ionotropic glutamate receptors, there has been little measure of its potency on other receptors in brain tissue. Although we previously reported that phencyclidine stimulated cloned-dopamine D2Long and D2Short receptors, others reported that phencyclidine did not stimulate D2 receptors in homogenates of rat brain striatum....
Synapse (New York, N.Y.)
July 1, 2006
Juan Liu, Toshihito Suzuki, Tatsunori Seki et al.
Dysfunctional maturation of neural networks, particularly hippocampus-prefrontal networks, may be of particular interest in determining the pathophysiology of schizophrenia. Phencyclidine (PCP)-induced symptoms in humans appear to offer a more complete model of schizophrenia than do amphetamine-induced symptoms. This study investigated the effects of intermittent i.p. injections of PCP (7.5...
Synapse (New York, N.Y.)
December 15, 2005
Philip Seeman, Mercedes Lasaga
Although the psychotomimetic action of phencyclidine is often used to model a hypoglutamate theory of psychosis or schizophrenia, work also exists showing that phencyclidine has a significant affinity for the dopamine D2 receptor. The present study was done to determine whether phencyclidine has a direct functional dopamine-like action on cells. The effect of phencyclidine was tested on the...
Synapse (New York, N.Y.)
December 1, 2005
Matthew Schmidt, Mark S Schmidt, Eduardo R Butelman et al.
85 citations
Salvinorin A, a potent hallucinogen isolated from the leaves of Salvia divinorum, has gained popularity among adolescents in the USA. No detailed study of the pharmacokinetics has been conducted in vivo. The present study investigates the in vivo pharmacokinetics of salvinorin A (0.032 mg/kg, i.v. bolus) in rhesus monkeys (n=4, 2 male, 2 female). The elimination t(1/2) was rapid (56.6+/-24.8...
Synapse (New York, N.Y.)
July 2003
Christopher D Verrico, J David Jentsch, Robert H Roth
Long-term abuse of delta-9-tetrahydrocannabinol (THC), the major psychoactive constituent of marijuana, produces behavioral and metabolic signs of frontal cortical dysfunction in humans; these effects persist even after short-term abstinence. Based on a preliminary finding that repeated administration of THC to rats reduces basal frontal cortical dopamine turnover (Jentsch et al. [1998]...
Synapse (New York, N.Y.)
August 1996
X M Gao, C A Tamminga
Phencyclidine (PCP) is a psychotomimetic drug associated with acute and delayed mental effects in normal humans and psychosis exacerbation in already psychotic schizophrenic individuals. We have previously described a dose-sensitive, delayed action of PCP on regional cerebral metabolism in the rat which occurs over 48 hours and a late (24 hour) change in N-methyl-d-aspartate (NMDA) and kainate...
Synapse (New York, N.Y.)
April 1996
K Nishijima, A Kashiwa, A Hashimoto et al.
We have examined the effects of schizophrenomimetic drugs including phencyclidine (PCP) and methamphetamine (MAP) on cortical and striatal dopamine (DA) metabolism using an in vivo dialysis technique in the rat. An acute systemic injection of PCP (2.5-10 mg/kg, intraperitoneally (i.p.)) dramatically increased concentrations of DA, 3,4-dihydroxy-phenylacetic acid, and homovanillic acid in the...
Synapse (New York, N.Y.)
1994
C B Goodman, D N Thomas, A Pert et al.
[3H]TCP, an analog of the dissociative anesthetic phencyclidine (PCP), binds with high affinity to two sites in guinea pig brain membranes, one that is MK-801 sensitive and one that is not. The MK-801-sensitive site (PCP site 1) is associated with NMDA receptors, whereas the MK-801-insensitive site (PCP site 2) may be associated with biogenic amine transporters (BAT). Although several "BAT...
Synapse (New York, N.Y.)
August 1, 1991
H C Akunne, A A Reid, A Thurkauf et al.
Previous work demonstrated two high-affinity PCP binding sites in guinea pig brain labeled by [3H]TCP (1-(1-[2-thienyl]cyclohexyl)piperidine): site 1 (N-methyl-D-aspartate [NMDA]-associated) and site 2 (dopamine-reuptake complex associated). The present study examined brain membranes prepared from various species, including human, for the presence of site 2, defined as binding in the presence...
Synapse (New York, N.Y.)
January 1991
B L Strehler
The enigmatic nature of the experience of self-awareness is examined in the light of recent discoveries and, on this basis, combined with inferences derived introspectively from the experience of the phenomenon itself; a specific physical locus of this experience within the human brains is deduced-proposed. The fundamental premise in this work is that whereever conscious self-awareness is...