There are defined hypothalamic functions in the genesis of thirst, but little is known of the cortical processes subserving consciousness of thirst notwithstanding the medical disorders that occur in psychiatric illness, addiction, and the attested decline of thirst with aging. In 10 adult males, positron emission tomography scans were made (i) during genesis of moderate thirst by infusion of...
Nagel has argued that the ‘mind-body’ problem, as traditionally conceived, is insoluble. His challenge to philosophers is to devise a metaphysical scheme that incorporates materialist concepts in describing first person experience and mentalistic concepts in describing third person experience, such that the internal relations between the concepts thereby constructed are necessary. Nagel's own...
Previously, serotonin (5-HT) was found to induce a marked increase in glutamatergic spontaneous excitatory postsynaptic currents (EPSCs) in apical dendrites of layer V pyramidal cells of prefrontal cortex; this effect was mediated by 5-HT2A receptors, a proposed site of action of hallucinogenic and atypical antipsychotic drugs. Unexpectedly, although the effect of 5-HT was Ca2+-dependent and...
Ibogaine has been shown to affect biogenic amine levels in selected brain regions. Because of the involvement of these neurotransmitters in drug addiction, the effects of ibogaine on biogenic amine transport may contribute to the potential anti-addictive properties of ibogaine in vivo. With rat brain synaptosomes as our experimental system, we measured the effects of ibogaine on the uptake and...
Ibogaine (Endabuse) is a psychoactive indole alkaloid found in the West African shrub, Tabernanthe iboga. This drug interrupts cocaine and amphetamine abuse and has been proposed for treatment of addiction to these stimulants. However, the mechanism of action that explains its pharmacological properties is unclear. Since previous studies demonstrated differential effects of psychotomimetic...
The theory of consciousness proposed by O'Brien & Opie is open to the Sorites paradox, for it defines a consciousness system internally in terms of computationally relevant units which add up to consciousness only if sufficient in number. The Sorites effect applies on the assumed level of features.
Symptoms of dependence and withdrawal after the frequent administration of high doses (210 mg/day) of oral delta9-tetrahydrocannabinol (THC) have been reported, yet little is known about dependence on lower oral THC doses, more relevant to levels attained by smoking marijuana. In a 20-day residential study, male (n = 6) and female (n = 6) marijuana smokers worked on five psychomotor tasks...
The function of the central cannabinoid receptor (CB1) was investigated by invalidating its gene. Mutant mice did not respond to cannabinoid drugs, demonstrating the exclusive role of the CB1 receptor in mediating analgesia, reinforcement, hypothermia, hypolocomotion, and hypotension. The acute effects of opiates were unaffected, but the reinforcing properties of morphine and the severity of...
There has been considerable interest in the potential of N-methyl-D-aspartate (NMDA) receptor antagonists in the treatment of a diverse group of neurological disorders including cerebral ischemia and neurodegeneration. The amino acids L-glutamate and L-aspartate have been shown to possibly mediate excitatory synaptic transmission in the central nervous system (CNS) via selective excitatory...
Heterocycles1999Haruhisa Shirahama, Kazuyo Sogawa, Kimiko Hashimoto1 citation
H-D exchange experiment?were performed on psilocin (1) and its analogs in MeOH-d,.The various exchange rates depending on their C3- suhstituents were observed.The exchange of bufotenine (5) and 5hydroxyindole ( 7) is much slower than psilocin (1) and its analogs (2 -4).Psilocin ( 1) is a hallucinogenic principle isolated from the poisonous mushroom, Psilocybe rnericanq' and it was recently...