Influence of changes in brain monoamine metabolism on behaviour of herpes simplex-infected mice

Abstract

In herpes simplex virus (HSV)-infected mice hypermotility was observed associated with an increased release of transmitter from adrenergic neurons. Inhibition of dopamine (DA) metabolism by the administration of α-methyltyrosine to the infected mice decreased motility rate counts while p-chlorophenylalanine, by inhibiting the formation of 5-hydroxytryptamine (5-HT) caused an increase in rate of motility. Pimozide and phenoxybenzamine, used for blocking DA and noradrenaline (NA) receptors, respectively, were both observed to reduce the hypermotility efficiently. Administration of FLA-63 as an inhibitor of NA-metabolism was associated with increased death rates in HSV-infected mice. Changes in behaviour towards aggression were encountered when levodopa was administered to HSV-infected mice and when apomorphine and clonidine were used for stimulation of the receptor functions of adrenergic neurons. The observations reported suggest that hypermotility, excitation and aggression might all be symptoms associated with a pathologically increased activity of adrenergic neurons.