Haemorrhage-induced release of noradrenaline, 5-hydroxytryptamine and uric acid in the supraoptic nucleus of the rat, measured by microdialysis.
Concentrations of monoamines and metabolites and uric acid were measured in sequential 15-min microdialysis samples taken from the area of the supraoptic nucleus (SON) in 9 urethane-anaesthetized rats. A decrease in blood pressure of 40 mm Hg was induced by withdrawing 3-4 ml of blood from an indwelling jugular catheter. This decreased blood pressure was maintained for 30 min and produced a significant rise in the concentrations of noradrenaline (NA) and its metabolite 4-hydroxy-3-methoxyphenylethan-1,2-diol (MHPG) and also in 5-hydroxytryptamine (5-HT) and the purine metabolite uric acid (UA). When blood pressure was returned to normal by replacing the withdrawn blood, the concentrations of NA, MHPG, 5-HT and UA returned to pre-haemorrhage levels within 15 min. No significant changes in concentrations of dopamine and its metabolites were found, and in 7 control animals sampled 1.5-2 mm away from the SON, in the area of the olfactory tubercle, concentrations of NA, MHPG, 5-HT and UA were not significantly altered by haemorrhage-induced decreases in blood pressure.
D000818:Animals; D002543:Cerebral Hemorrhage / Q000378:metabolism*; D003956:Dialysis; D004298:Dopamine / Q000378:metabolism; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D013495:Supraoptic Nucleus / Q000378:metabolism*; D014527:Uric Acid / Q000378:metabolism*
D014527:Uric Acid; D012701:Serotonin; D008734:Methoxyhydroxyphenylglycol; D006897:Hydroxyindoleacetic Acid; D004298:Dopamine; D009638:Norepinephrine