Concomitant hypotensive and antinociceptive effects of guanabenz in conscious rats: involvement of nucleus reticularis gigantocellularis.
Subcutaneous administration of guanabenz (1, 2, 5, or 8 mg/kg) in conscious Sprague-Dawley rats exerted concomitant suppressive actions on systolic pressure (tail-cuff sphygmomanometric measurement) and pain responses (hot-plate algesio-metric assay) that varied both in degree (antinociception much greater than hypotension) and response pattern. Furthermore, both depressive effects were appreciably attenuated by bilateral lesions of the nucleus reticularis gigantocellularis in the medulla oblongata. It is speculated that separate subpopulations of neurons within this reticular nucleus may be involved in the expression of hypotension and antinociception by this amino-guanidine derivative.
Lim
H C
HC
Department of Physiology, Faculty of Medicine, National University of Singapore, Kent Ridge.
Chong
O K
OK
Chan
S H
SH
D000698:Analgesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D006143:Guanabenz / Q000494:pharmacology*; D006146:Guanidines / Q000494:pharmacology*; D007608:Kainic Acid / Q000494:pharmacology; D008297:Male; D008526:Medulla Oblongata / Q000187:drug effects / Q000502:physiology*; D010147:Pain Measurement; D051381:Rats; D011919:Rats, Inbred Strains
D006146:Guanidines; D006143:Guanabenz; D007608:Kainic Acid