Catecholamine-like substances

Fig. (6). Catecholamine-like Substances in the Rhizomes of Astilbe thunbergii...

Owing to its equally high af nity for all a-and p-receptors, epinephrine does not permit selective activation of a particular receptor subtype. Like most catecholamines, it is also unsuitable for oral administration (cat-echole is a trivial name for o-hydroxyphe-nol). Norepinephrine differs from epinephrine by its high af nity for a-receptors and low af nity for p2-receptors. The converse holds true for the synthetic substance, isoproterenol (isoprenaline) (A). 

Some genes which show late expression after addition of CDF/LIF have been identified. For example, in cultured sympathetic neurons CDF/LIF induces transcription of not only the acetylcholine gene, but also the genes coding for substance P, somatostatin, cholecystokinin, enkephalin and vasoactive intestinal polypeptide (Nawa and Patterson, 1990 Fann and Patterson, 1994). The transcription of muscarinic acetylcholine receptor genes and substance P receptor genes is also induced (Ludlam et al., 1994). On the other hand, CDF/LIF suppresses catecholamine synthesis. In osteoblast-like cells, LIF suppresses alkaline... 

A special feature at the application of NH2 precoated layers is the fact, that a large number of sample substances (like carbohydrates and catecholamines) can be transferred into stable fluorescing compounds only by heating them on this precoated plate (150-153). 

Reserpine (Fig. 4), an alkaloid extracted from Rauwolfia serpentina, and many other natural or synthetic substances block the storage of monoamines (catecholamines as well as 5-HT) the resulting depletion of the amine stores is accompanied by a rise of acidic metabolites in the urine. This property of reserpine-like compounds to deplete monoamines stores has great experimental and clinical value... 

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