Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-2072
    Keywords: Haloperidol ; Clozapine ; Neuroleptics ; Tremor ; Response force ; Power spectra ; Forelimb ; rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In order to detect putative differences in the behavioral effects of clozapine and haloperidol, rats were trained to use a single forelimb to exert continuous pressure on a force-sensing operandum. Behavior was maintained by presenting a water-filled dipper for consumption only as long as the force remained above a specified level (the water fountain task). Effects of clozapine (2.0, 4.0, 8.0 mg/kg) and haloperidol (0.02, 0.04, 0.08, 0.12 mg/kg) on the forelimb force oscillations manifested during the operandum pressing episodes were analyzed with power spectral analysis and other quantitative methods. All rats exhibited force oscillations with a fundamental frequency near 7 Hz. Clozapine shifted the frequency to lower values (i.e., oscillation slowing), while haloperidol shifted oscillations to slightly higher frequencies. Moreover, clozapine reduced power in the region of the spectrum above 5 Hz. In contrast, haloperidol tended to increase power in these regions. Time domain analyses of the force-time waveforms indicated that haloperidol increased force emission during the hold phase of the forelimb response, and clozapine decreased this measure. The results are congruent with the high extrapyramidal side effects of haloperidol and the lack of such effects of clozapine in the clinic. In addition, clozapine may have antitremor effects in rats as it does in humans.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-2072
    Keywords: Key words Clozapine ; Haloperidol ; Subchronic ; Tolerance ; Forelimb ; Force ; Tremor ; Neuroleptics ; Atypical ; Antipsychotic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In order to compare and contrast the behavioral effects of the typical neuroleptic haloperidol with the atypical neuroleptic clozapine, ten daily doses of these drugs were administered to separate groups of rats trained to extend the forelimb through a rectangular hole and to exert downward pressure on a force transducer to gain access to water. Doses were individually titrated daily for each rat in an attempt to achieve a 50% reduction in time on task (analogous to response rate) during 8-min daily sessions. Clozapine-treated rats exhibited dramatic tolerance to the drug’s suppressive effect on time on task. In contrast, haloperidol rats displayed little tolerance on this measure. Despite the tolerance reflected by time on task, no tolerance was seen in clozapine’s marked slowing of the dominant frequency of oscillations in forelimb force as measured by Fourier analysis of the force-time recordings. Haloperidol did not slow the dominant frequency. No tolerance was seen for clozapine’s effects on forelimb force or tremor measures. Haloperidol did not significantly affect forelimb force. Both haloperidol and clozapine produced increases in the duration of long-duration forelimb responses, and no tolerance was seen for either drug on this measure of behavior. For clozapine, the dissociation between the tendency to respond (time on task) and the observed slowing of the dominant frequency may reflect effects peculiar to atypical neuroleptics, while the lengthening of long-duration responses by both drugs may reflect a more general behavioral effect that is characteristic of both typical and atypical antipsychotic drugs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...