ISSN:
1432-1912
Keywords:
Spreading Depression
;
Neostriatum
;
Dopamine
;
Catalepsy
;
Stereotyped Behaviour
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Changes in drug-induced catalepsy and stereotyped behaviour were investigated in the rat following the intrastriatal application of 1 μl 25% w/v KCl which was shown to reduce striatal electrical activity. The unilateral or bilateral application of KCl to normal animals caused contralateral circling or stereotyped biting and gnawing respectively. These effects were differentiated from injection artifact. The cataleptic actions of haloperidol, fluphenazine, loxapine, oxypertine or metaclopramide were modified biphasically by bilateral intrastriatal KCl: catalepsy was initially reversed and stereotypy developed but, subsequently, catalepsy was intensified. Unilateral injections of KCl also reversed catalepsy and marked contralateral circling activity developed. These actions of intrastriatal KCl, both in normal and cataleptic animals, were abolished by lesions of the substantia nigra. RS 86 catalepsy was potentiated both by uni-and bilateral intrastriatal injections of KCl whilst similar injections failed to modify the depressant effects of IB 503, chloral hydrate, diazepam, clozapine or a combination of reserpine/α-methyl-ptyrosine. Morphine catalepsy was modified by intrastriatal KCl more in the manner of the stereotypic agents (D-and L-amphetamine, apomorphine, methylphenidate, ET 495), this being the production of ipsilateral circling following unilateral KCl or the induction of a state of immobility following bilateral injections (concomitant with antagonism of stereotypy or enhancement of morphine catalepsy). The mild stereotypic and tremorogenic activities of amantadine and NBT I were unmodified by intrastriatal KCl. Similarly, bilateral KCl failed to modify the abnormal motor movements observed after an L-Dopa/nialamide pretreatment, although a contralateral asymmetry was recorded following unilateral injections. The actions of intrastriatal KCl upon D-amphetamine stereotypy were mimicked by the cortical application of KCl at times prior to passage of the ‘spreading depression’ to the striatal area. However, at similar times, the effects of intrastriatal KCl on normal animal behaviour or upon haloperidol catalepsy were not reproduced by KCl applied to the cortex. Results are discussed in terms of the neostriatal dopaminergic mechanisms involved in the mediation of the behavioural effects used as the bases of tests for antiparkinson and neuroleptic agents.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00501147
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