Tags

Type your tag names separated by a space and hit enter

Impact of grafted serotonin and dopamine neurons on development of L-DOPA-induced dyskinesias in parkinsonian rats is determined by the extent of dopamine neuron degeneration.
Brain. 2009 Feb; 132(Pt 2):319-35.B

Abstract

Previous studies have shown that serotonin neurons play an important role in the induction and maintenance of L-DOPA-induced dyskinesia in animals with lesion of the nigrostriatal dopamine system. Patients with Parkinson's disease that receive transplants of foetal ventral mesencephalic tissue, the graft cell preparation is likely to contain, in addition to dopamine neurons, serotonin neurons that will vary in number depending on the landmarks used for dissection. Here, we have studied the impact of grafted serotonin neurons--alone or mixed with dopamine neurons--on the development of L-DOPA-induced dyskinesia in rats with a partial 6-hydroxydopamine lesion of the host nigrostriatal projection. In these rats, which showed only low-level dyskinesia at the time of transplantation, serotonin grafts induced a worsening in the severity of dyskinesia that developed during continued L-DOPA treatment, while the dopamine-rich graft had the opposite, dampening effect. The detrimental effect seen in animals with serotonin neuron grafts was dramatically increased when the residual dopamine innervation in the striatum was removed by a second 6-hydroxydopamine lesion. Interestingly, rats with grafts that contained a mixture of dopamine and serotonin neurons (in approximately 2:1) showed a marked reduction in L-DOPA-induced dyskinesia over time, and the appearance of severe dyskinesia induced by the removal of the residual dopamine innervation, seen in the animals with transplants of serotonin neurons alone, was blocked. FosB expression in the striatal projection neurons, which is associated with dyskinesias, was also normalized by the dopamine-rich grafts, but not by the serotonin neuron grafts. These data indicate that as long as a sufficient portion, some 10-20%, of the dopamine innervation still remains, the increased host serotonin innervation generated by the grafted serotonin neurons will have limited effect on the development or severity of L-DOPA-induced dyskinesias. At more advanced stages of the disease, when the dopamine innervation of the putamen is reduced below this critical threshold, grafted serotonin neurons are likely to aggravate l-DOPA-induced dyskinesia in those cases where the dopamine re-innervation derived from the grafted neurons is insufficient in magnitude or do not cover the critical dyskinesia-inducing sub-regions of the grafted putamen. We conclude that it is not the absolute number of serotonin neurons in the grafts, but the relative densities of dopamine and serotonin innervations in the grafted striatum that is the critical factor in determining the long-term effect of foetal tissue graft, beneficial or detrimental, on dyskinesia in grafted Parkinson's disease patients.

Authors+Show Affiliations

Department Experimental Medical Science, Wallenberg Neuroscience Center, Lund University, BMC D11, Lund, Sweden.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

19039008

Citation

Carlsson, Thomas, et al. "Impact of Grafted Serotonin and Dopamine Neurons On Development of L-DOPA-induced Dyskinesias in Parkinsonian Rats Is Determined By the Extent of Dopamine Neuron Degeneration." Brain : a Journal of Neurology, vol. 132, no. Pt 2, 2009, pp. 319-35.
Carlsson T, Carta M, Muñoz A, et al. Impact of grafted serotonin and dopamine neurons on development of L-DOPA-induced dyskinesias in parkinsonian rats is determined by the extent of dopamine neuron degeneration. Brain. 2009;132(Pt 2):319-35.
Carlsson, T., Carta, M., Muñoz, A., Mattsson, B., Winkler, C., Kirik, D., & Björklund, A. (2009). Impact of grafted serotonin and dopamine neurons on development of L-DOPA-induced dyskinesias in parkinsonian rats is determined by the extent of dopamine neuron degeneration. Brain : a Journal of Neurology, 132(Pt 2), 319-35. https://doi.org/10.1093/brain/awn305
Carlsson T, et al. Impact of Grafted Serotonin and Dopamine Neurons On Development of L-DOPA-induced Dyskinesias in Parkinsonian Rats Is Determined By the Extent of Dopamine Neuron Degeneration. Brain. 2009;132(Pt 2):319-35. PubMed PMID: 19039008.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Impact of grafted serotonin and dopamine neurons on development of L-DOPA-induced dyskinesias in parkinsonian rats is determined by the extent of dopamine neuron degeneration. AU - Carlsson,Thomas, AU - Carta,Manolo, AU - Muñoz,Ana, AU - Mattsson,Bengt, AU - Winkler,Christian, AU - Kirik,Deniz, AU - Björklund,Anders, Y1 - 2008/11/27/ PY - 2008/11/29/pubmed PY - 2009/3/11/medline PY - 2008/11/29/entrez SP - 319 EP - 35 JF - Brain : a journal of neurology JO - Brain VL - 132 IS - Pt 2 N2 - Previous studies have shown that serotonin neurons play an important role in the induction and maintenance of L-DOPA-induced dyskinesia in animals with lesion of the nigrostriatal dopamine system. Patients with Parkinson's disease that receive transplants of foetal ventral mesencephalic tissue, the graft cell preparation is likely to contain, in addition to dopamine neurons, serotonin neurons that will vary in number depending on the landmarks used for dissection. Here, we have studied the impact of grafted serotonin neurons--alone or mixed with dopamine neurons--on the development of L-DOPA-induced dyskinesia in rats with a partial 6-hydroxydopamine lesion of the host nigrostriatal projection. In these rats, which showed only low-level dyskinesia at the time of transplantation, serotonin grafts induced a worsening in the severity of dyskinesia that developed during continued L-DOPA treatment, while the dopamine-rich graft had the opposite, dampening effect. The detrimental effect seen in animals with serotonin neuron grafts was dramatically increased when the residual dopamine innervation in the striatum was removed by a second 6-hydroxydopamine lesion. Interestingly, rats with grafts that contained a mixture of dopamine and serotonin neurons (in approximately 2:1) showed a marked reduction in L-DOPA-induced dyskinesia over time, and the appearance of severe dyskinesia induced by the removal of the residual dopamine innervation, seen in the animals with transplants of serotonin neurons alone, was blocked. FosB expression in the striatal projection neurons, which is associated with dyskinesias, was also normalized by the dopamine-rich grafts, but not by the serotonin neuron grafts. These data indicate that as long as a sufficient portion, some 10-20%, of the dopamine innervation still remains, the increased host serotonin innervation generated by the grafted serotonin neurons will have limited effect on the development or severity of L-DOPA-induced dyskinesias. At more advanced stages of the disease, when the dopamine innervation of the putamen is reduced below this critical threshold, grafted serotonin neurons are likely to aggravate l-DOPA-induced dyskinesia in those cases where the dopamine re-innervation derived from the grafted neurons is insufficient in magnitude or do not cover the critical dyskinesia-inducing sub-regions of the grafted putamen. We conclude that it is not the absolute number of serotonin neurons in the grafts, but the relative densities of dopamine and serotonin innervations in the grafted striatum that is the critical factor in determining the long-term effect of foetal tissue graft, beneficial or detrimental, on dyskinesia in grafted Parkinson's disease patients. SN - 1460-2156 UR - https://www.unboundmedicine.com/medline/citation/19039008/Impact_of_grafted_serotonin_and_dopamine_neurons_on_development_of_L_DOPA_induced_dyskinesias_in_parkinsonian_rats_is_determined_by_the_extent_of_dopamine_neuron_degeneration_ L2 - https://academic.oup.com/brain/article-lookup/doi/10.1093/brain/awn305 DB - PRIME DP - Unbound Medicine ER -