Association between hypoalgesia and hypertension in rats after short-term isolation

doi:10.1016/0028-3908(85)90176-5

Neuropharmacology

Volume 24, Issue 2, February 1985, Pages 167-171

https://doi.org/10.1016/0028-3908(85)90176-5 Get rights and content

Abstract

By isolating young rats (90–100 g) a state of hypertension and tachycardia was induced after 7 days or a longer period of social deprivation. Clonidine, a drug used to treat hypertension in man, readily reversed the high blood pressure and heart rate in this experimental model of hypertension. In two different tests, an elevated nociceptive threshold was shown to be present in isolated animals as compared to group-housed rats. Naloxone was found to reverse this hypoalgesic state. The opiate antagonist also diminished the high blood pressure in the socially-deprived animals. Moreover, after 7 days of isolation, 24 hr of housing the rats in groups of five made the level of blood pressure and the sensitivity to pain return to control values. In this experimental model, in which hypertension was linked to stressful housing conditions, the data suggest that high blood pressure and hypoalgesia are closely associated.

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Association between hypoalgesia and hypertension in rats after short-term isolation

Abstract

Brain Res.

Brain Res.

Brain Res.

Peptides

Biochem. Pharmac.

Brain Res.

Eur. J. Pharmac.

Eur. J. Pharmac.

Brain Res.

Brain Res.

Brain Res.

Costicosteroid involvement in the changes in noradrenergic responsiveness of tissues from rats made hypertensive by short-term isolation

Br. J. Pharmac.

Reversal of 6-hydroxydopamine-induced hypotension in the rat without activation of the renin-angiotensin system

J. Physiol.