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PubMed · 9519283

Age-related decrease in centrally-mediated pressor response to clonidine in conscious rats.

H Kawasaki·H Araki·K Futagami·Y Gomita
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Abstract

An age-related change in pressor response to intracerebroventricular (i.c.v.) injection of clonidine in conscious rats was investigated. In 15-week-old rats, clonidine (2 to 20 micrograms) caused a dose-dependent pressor response concomitant with decrease in heart rate. The depressor response to i.c.v. clonidine at lower doses (2 and 5 micrograms) but not higher doses (10 and 20 micrograms) was observed. The pressor response to clonidine in 20- and 30-week-old rats was markedly diminished, and the depressor response appeared at any of the doses injected. However, no age-related change in heart rate responses was observed. These results suggest that the centrally mediated pressor response to clonidine is age-related and masks the depressor response.

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Adrenergic alpha-AgonistsAgingAnimalsAntihypertensive AgentsBlood PressureBrainClonidineDose-Response Relationship, DrugElectroencephalographyHeart RateInjections, IntraventricularMaleRatsRats, WistarJournal Article

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H Kawasaki, H Araki, K Futagami, Y Gomita. 1998-01-26. Age-related decrease in centrally-mediated pressor response to clonidine in conscious rats.. https://doi.org/10.1016/s0006-8993(97)01377-2

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