Rapid post mortem changes in 3,4‐dihydroxyphenylacetic acid (DOPAC), a dopamine metabolite, in rat striatum

Rapid Postmortem Increase in Extracellular Dopamine in the Rat Brain as Assessed by Brain Microdialysis

“…This finding, taken together with evidence that the level of DA in whole brain tissue remains constant over 5 min after death (Moleman et al, 1977;Ikarashi et al, 1985;Vulto et al, 1986), suggests that immediately after death there is a marked decrease in the size of the intraneuronal DA pool. This finding, taken together with evidence that the level of DA in whole brain tissue remains constant over 5 min after death (Moleman et al, 1977;Ikarashi et al, 1985;Vulto et al, 1986), suggests that immediately after death there is a marked decrease in the size of the intraneuronal DA pool.…”

“…The steady decline in the amounts of DOPAC and HVA in the brain dialysates over the first hour postmortem was an unexpected finding in view of other studies showing an increase in the concentrations of these metabolites within about 30 min of death (Moleman et al, 1977;Ikarashi et al, 1985). However, on death monoamine oxidase activity, and therefore the production of the acid DA metabolites, is likely to be markedly reduced and furthermore it is probable that metabolite clearance to the blood is seriously impaired.…”

“…Whereas marked postmortem changes in the levels of these catechols occur over periods of tens of minutes (e.g., Wiesel and Sedvall, 1974;Moleman et al, 1977;Ikarashi et al, 1985), it is generally assumed that rapid dissection and cooling of the tissue within 5 min of decapitation avoids dramatic changes of the DA system. Whereas marked postmortem changes in the levels of these catechols occur over periods of tens of minutes (e.g., Wiesel and Sedvall, 1974;Moleman et al, 1977;Ikarashi et al, 1985), it is generally assumed that rapid dissection and cooling of the tissue within 5 min of decapitation avoids dramatic changes of the DA system.…”

“…Analysis of the content of 3,4-dihydroxyphenylethylamine (dopamine, DA) and its main free acidic metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in postmortem rat brain tissue is an established experimental approach to study the biochemistry and pharmacology of the central DA transmitter system. Whereas marked postmortem changes in the levels of these catechols occur over periods of tens of minutes (e.g., Wiesel and Sedvall, 1974;Moleman et al, 1977;Ikarashi et al, 1985), it is generally assumed that rapid dissection and cooling of the tissue within 5 min of decapitation avoids dramatic changes of the DA system. We have recently questioned this issue in an article that showed that measurable changes in striatal whole tissue levels of DOPAC and HVA occur within 2 min following decapitation (Vulto et al, 1986).…”

Free and conjugated 3, 4-dihydroxyphenylacetic acid and homovanillic acid in brain dopaminergic areas at basal state and after pipotiazine activation

“…The hypothalamus was obtained from the fourth 4 mm brain section by cutting vertically at the level oftelencephalic-diencephalic junction and horizontally at the level of the rhinal sulcus. The total dissection was performed within 5 min a time which should not affect DOPAC levels in brain areas (Moleman et al, 1977). The brain tissues were rapidly frozen and stored at -60 ~ until analysis.…”