engleski

Diabetes Mellitus and the Central Nervous System

Central nervous system has not been usually thought of as a target organ in diabetes mellitus. However, numerous structural, biochemical and behavioral alterations of central nervous system have been demonstrated in diabetes mellitus during the last two decades. The most prominent neurochemical alterations have been observed in neurotransmitter function. In agreement with that, certain mental and neurological, as well as neuroendocrinological disorders related to the neurotransmitter dysfunction appear more often in diabetes mellitus. Monoaminergic alterations in brain, probably most extensively studied so far, have been ascribed to reduced brain uptake of monoamine precursor amino acids. However, regional specificity of monoamine changes, as well as lack of concomitant regional specificity of blood brain barrier permeability for monoamine precursors in diabetes, argue against this hypothesis, supported by introduction of a new experimental model, animals with centrally applied drugs that are selectively toxic for insulin producing/secreting cells. Central, intracerebroventricular application of low, non-diabetogenic doses of these betacytotoxic drugs is accompanied by, in general, similar brain monoamine changes as peripheral administration of high, diabetogenic doses. This may be associated with described brain insulin system, that has regionally distributed insulin content and brain insulin receptors and specific insulin-monoamine interaction, and could be a missing link between monoaminergic alterations of central nervous system and diabetes mellitus. Although not clear yet, the relationship between the central and the peripheral insulin system is likely, as central administration of low betacytotoxic doses does not influence steady-state blood glucose level, but alters glucose tolerance.

diabetes mellitus; brain

nije evidentirano