Physiological modulators serotonin

Note the equation of an extremely stimulated imagination with a dreamlike state. From the facts that he found the daylight to be unpleasantly glaring and the corresponding release of an uninterrupted stream of fantastic pictures, we can safely conclude that Hofmann s LSD visions were produced by a dreamlike shift in the chemical balance of his visual brain. And, indeed, Hofmann himself offered the hypothesis that the stimulating effects on his visual brain were caused by LSD s interference with serotonin, the brain modulator that later physiological studies showed to be radically reduced in REM sleep. 

Despite the recent advances in molecular biology, the mechanisms of action and the physiological functions of the anandamide system remain obscure. It would appear that the cannabinoid receptors and the anandamides reside within the neurons. Thus unlike the classical neurotransmitters noradrenaline and serotonin, the anandamides are not released into the synaptic cleft and are not involved in intemeuronal communication. Instead the anandamides modulate the excitability and inhibitory responsiveness of neurons by acting on cannabinoid hetero-ceptors located on inhibitory and excitatory terminals. In this way, the... 

Serotonin modulates numerous physiological and behavioral systems in the human body and is involved in a wide variety of clinical disorders. In the ENS, for example, serotonin plays pivotal roles in the pathogenesis of the carcinoid syndrome and the irritable bowel syndrome. Differences in serotonin receptor subtypes provide a strong rationale for using pharmaceutical agents that selectively act on serotonin receptors in the treatment of these clinical disorders. ... 

Heterocycles also play an important role as endogenous neurotransmitters. Chief among them are serotonin and histamine, which are of paramount importance in modulating the body s physiological and biochemical processes. 

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