Ultra-low doses of methamphetamine suppress 5-hydroxytryptophan-induced head-twitch response in mice during aging.

The head-twitch response (HTR) in mice is considered a behavioral assay for activation of 5-HT 2A receptors in rodents. It can be evoked by direct-acting 5-HT 2A receptor agonists such as (±)-2,5-dimethoxy-4-iodoamphetamine, 5-hydroxytryptamine precursors [e.g.

Effects of low-doses of methamphetamine on d-fenfluramine-induced head-twitch response (HTR) in mice during ageing and c-fos expression in the prefrontal cortex.

Background: The head-twitch response (HTR) in mice is considered a behavioral model for hallucinogens and serotonin 5-HT receptor function, as well as Tourette syndrome in humans. It is mediated by 5-HT receptor agonists such as ( ±)- 2,5-dimethoxy-4-iodoamphetamine (DOI) in the prefrontal cortex (PFC). The 5-HT antagonist EMD 281014, can prevent both DOI-induced HTR during ageing and c-fos expression in different regions of PFC.

Vigilance, arousal, and acetylcholine: Optimal control of attention in a simple detection task.

Paying attention to particular aspects of the world or being more vigilant in general can be interpreted as forms of 'internal' action. Such arousal-related choices come with the benefit of increasing the quality and situational appropriateness of information acquisition and processing, but incur potentially expensive energetic and opportunity costs. One implementational route for these choices is widespread ascending neuromodulation, including by acetylcholine (ACh).

An ontogenic study of receptor mechanisms by which acute administration of low-doses of methamphetamine suppresses DOI-induced 5-HT-receptor mediated head-twitch response in mice.

Background: Methamphetamine (MA) is a non-selective monoamine releaser and thus releases serotonin (5-HT), norepinephrine (NE) and dopamine (DA) from corresponding nerve terminals into synapses. DOI ((±)-2, 5-dimethoxy-4-iodoamphetamine) is a direct-acting serotonergic 5-HT receptor agonist and induces the head-twitch response (HTR) via stimulation of 5-HT receptor in mice. While more selective serotonin releasers such as d-fenfluramine evoke the HTR, monoamine reuptake blockers (e.

Central and peripheral emetic loci contribute to vomiting evoked by the Akt inhibitor MK-2206 in the least shrew model of emesis.

Akt (protein kinase B) signaling is frequently activated in diverse cancers. Akt inhibitors such as perifosine and MK-2206 have been evaluated as potential cancer chemotherapeutics. Although both drugs are generally well tolerated, among their most common side-effects vomiting is a major concern.