Recent studies suggest that the mesocortico-frontal dopaminergic neurones which originate in the ventral tegmental area (VTA) have an inhibitory role in locomotor activity1,2. They are also markedly activated under stress3–5. This effect was shown in rats and mice subjected to electric foot-shocks by measuring either the rate of decline of dopamine (DA) after α-methylparatyrosine treatment3 or the changes in dihydroxyphenylacetic acid (dopac) levels and the dopac/DA ratio4–6. In rats, stress-induced activation of the dopaminergic neurones was prevented by benzodiazepines4,5, and studies in BALB/c mice introduced for 2 min into an open field further established the role of dopaminergic neurones in emotional responses7. These observations led us to examine the effects of long-term isolation on the activity of the mesocortico-frontal dopaminergic neurones in rats, some of which were subjected to a stressful situation. Indeed, several groups have reported that long-term isolation in rodents induced behavioural disturbances such as increased motor activity8,9 and aggression9,10 and hyper-reactivity to a new environment or stressful stimuli10,11. As measured by the changes in dopac levels or the dopac/DA ratio, we report here that the activity of the mesocortico-frontal dopaminergic neurones was reduced after isolation. This was not the case for the dopaminergic neurones projecting to the nucleus accumbens or the striatum, the rate of DA utilisation in these structures was even enhanced in isolated rats in which the activity of the mesocortico-frontal dopaminergic neurones was markedly reduced. Finally, we will show that a 3-min electric foot-shock session is more effective in enhancing dopac levels or the dopac/DA ratio in the frontal cortex of isolated than grouped rats.
Access optionsAccess options
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Tassin, J. P. et al. Brain Res. 141, 267–281 (1978).
Carter, C. J. & Pycock, D. J. Br. J. Pharmac. 64, 430P (1978).
Thierry, A. M., Tassin, J. P., Blanc, G. & Glowinski, J. Nature 263, 242–244 (1976).
Lavielle, S. et al. Brain Res. 168, 585–594 (1979).
Fadda, F. et al. Life Sci. 27, 2219–2224 (1978).
Hervé, D. et al. Life Sci. 25, 1659–1664 (1979).
Tassin, J. P., Hervé D., Blanc, G. & Glowinski, J. Neurosci. Lett. (in the press).
Weinstock, M., Speiser, Z. & Ashkenazi, R. Psychopharmacology 56, 205–209 (1978).
Valzelli, L. Psychopharmacologia 31, 305–320 (1973).
Welch, A. S. & Welch, B. L. 91–142 (Plenum, New York, 1971).
Brain, P. & Benton, D. Life Sci. 24, 99–116 (1979).
Gauchy, C., Tassin, J. P., Glowinski, J. & Chéramy, A. J. Neurochem. 26, 99–104 (1976).
Sheving, L. E., Harrison, W. H., Gordon, N. P. & Pauly, J. E. Am. J. Physiol. 214, 166–173 (1968).
Thoa, N., Tizabi, Y. & Jacobowitz, D. Brain Res. 131, 259–269 (1977).
Lisoprawski, A., Hervé, D., Blanc, G., Glowinski, J. & Tassin, J. P. Brain Res. 183, 229–234 (1980).
Hervé, D. et al. Neurosci. Lett. 15, 127–133 (1979).
LeMoal, M. et al. Adv. biochem. Psychopharmac. 16, 237–245 (1977).
Brozoski, T. S., Brown, R. M., Rosvold, H. E. & Goldman, P. S. Science 205, 929 (1979).
Simon, H., Scatton, B. & Le Moal, M. Neurosci. Lett. 15, 319–324 (1979).
About this article
Behavioral and Noradrenergic Sensitizations in Vulnerable Traumatized Rats Suggest Common Bases with Substance Use Disorders
Molecular Neurobiology (2019)
BMC Gastroenterology (2014)
Changes in dopamine D2-receptor binding are associated to symptom reduction after psychotherapy in social anxiety disorder
Translational Psychiatry (2012)
Social isolation stress induces ATF-7 phosphorylation and impairs silencing of the 5-HT 5B receptor gene
The EMBO Journal (2010)
In rats chronically treated with clozapine, tyrosine depletion attenuates the clozapine-induced in vivo increase in prefrontal cortex dopamine and norepinephrine levels