PubMed HealthSearch

Biomedical subjects

L Decsi

Publications and source records attributed to L Decsi.

9 recordsLinked to original sources

Adrenergic modulation of a cholinergic emotional reaction in the cat's thalamus.

Direct carbachol stimulation of the intralaminar nuclei of the thalamus evokes an affective defense reaction in the cat. Pretreatment of the region with noradrenaline inhibited the reaction in a dose-related manner. Phenylephrine was ineffective in this respect while isoprenaline exhibited roughly the same inhibitory action as noradrenaline. The alpha-receptor blocking dihydroergotamine left the inhibitory effect of noradrenaline unaffected while the beta-receptor blocking propranolol abolished it. These findings suggest that the inhibitory effect of noradrenaline on the carbachol-induced thalamic emotional reaction is caused by its influence on beta-type adrenergic receptors. Since a similar adrenergic-cholinergic interaction was previously demonstrated also for the hypothalamus and red nucleus, it can be concluded that adrenergic modulation of cholinergic reactions in the central nervous sytem seems to be a principle of more general validity than has been assumed thus far.

Animals

Atropine stereotypy and its inhibition by intracaudate triperidol in the rat.

One component (rearing) of the stereotyped behavior of the rat was quantitated using erigometer, a new device developed in this laboratory. Intraperitoneal injection of atropine, but not methylatropine, caused dose-related stereotyped behavior in the rat and this effect was antagonized by intracaudate injection of triperidol in a dose-related manner. It is concluded that stereotypy can be evoked also in the case when the striatal dopaminergic tone is normal or even below normal: it is the equilibrium of the striatal cholinergic-dopaminergic systems which must be shifted towards dopamine, which is necessary for the development of this behavioral manifestation.

Animals