And aminergic-cholinergic interaction

The Heart of the Brain Neuromodulation and Aminergic-Cholinergic Interaction... 

Reciprocal Interaction Between Cholinergic REM-On and Aminergic REM-Off Cells... 

An imbalance in the cholinergic/aminergic interactions may result from the deficient activity of a certain aminergic system or the hyperactivity of the cholinergic system or any quantitative combination of the two, which could very well be responsible for the pathophysiology of depression (M. Berger and Riemann 1993 Soldatos and Paparrigopoulos 1995). 

An explanation for sleep EEG alterations in depression is provided by the well established monaminergic-cholinergic imbalance model [49] which includes monoaminergic dysfunction in depression. The result is a disturbance of the mutual interactions between the diverse nuclei which control the transitions between REM and nonREM states (see Fig. 7.5, right part). This concept was developed in close relation to the monamionergic-cholinergic imbalance model of depression [50] which is based on observations that inhibition of the aminergic system by re-... 

The reported neurochemical effects of lead are, as has been seen, enormous. They can be broadly summarized by neurotransmitter system cholinergic impairment at relatively high levels (usually in the presence of non-specific effects), dopaminergic effects at low levels, and impairment at higher levels (in the presence of obvious non-specific effects), GABAergic effects at levels where a complication from the interaction with D-amino laevulinic acid also occurs. There is also a mixed bag of effects on enkephalin, adenyl cyclase, 5-hydroxytrypamine and other putative aminergic neurotransmitters. 

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