Enhanced antinociception of clonidine in spontaneously hypertensive rats involves a presynaptic noradrenergic mechanism

Pharmacology, Biochemistry, and Behavior
Y WangJ C Lin

Abstract

We and others previously reported that the antinociceptive effect of clonidine, measured by the hot plate method, was greater in spontaneously hypertensive rats (SHRs) than in Wistar-Kyoto rats (WKYs). In the present study, we found that the difference in clonidine-induced analgesia between these two strains was abolished after lesioning the presynaptic noradrenergic neurons with N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4). Previous studies indicated that clonidine increases tissue norepinephrine (NE) content by inhibiting NE release. We found that the basal NE concentration in locus coeruleus (LC), as measured by HPLC-ECD, was not different between WKYs and SHRs. Systemic application of clonidine (0.69 mg/kg, I.P.) significantly increased the tissue content of NE in the SHRs, but not in WKYs. Using pressure microinjection and high-speed chronoamperometric recording techniques, we found that local application of KCl to the LC brain slices increased extracellular NE levels in both strains. Perfusion of slices with clonidine (1 microM) selectively attenuated KCl-evoked NE release in SHRs, suggesting that clonidine-induced presynapitc inhibition is more effective in SHRs than in WKYs. In conclusion, our data indicate that ...Continue Reading

References

Mar 24, 1992·European Journal of Pharmacology·M F Suaud-ChagnyF Gonon
Mar 1, 1991·Japanese Heart Journal·S KawasakiM Nakagawa
May 1, 1985·Pharmacology, Biochemistry, and Behavior·T L Yaksh
May 7, 1987·European Journal of Pharmacology·C PostE Sundström
Dec 1, 1985·Neuropharmacology·J S Mohrland, P F Von Voigtlander
Jul 1, 1973·Japanese Heart Journal·J Iriuchijima
Dec 16, 1982·Brain Research·J O SchenkR N Adams
Jan 9, 1984·Brain Research·G A GerhardtR N Adams
Oct 6, 1997·Clinical and Experimental Hypertension : CHE·J C LinY Wang

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Citations

Dec 26, 2012·Behavioural Brain Research·Michael TurnerEleanor J Dommett
Dec 14, 2011·The Journal of Pain : Official Journal of the American Pain Society·Ken-Ichiro HayashidaJames C Eisenach
Dec 2, 2004·Brain Research·Leandro Franco VendruscoloReinaldo Naoto Takahashi
Feb 24, 2001·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·B K TaylorA I Basbaum

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