Fetal human brainstem tissue including the nucleus locus coeruleus was transplanted to the anterior eye chamber of athymic nude rats. Most transplants survived and grew in the anterior chamber of the eye. After 9-15 months, the host animals were anesthetized and electrophysiological or in vivo electrochemical recordings were performed. The brainstem transplants contained spontaneously active neurons with regular single-spike firing patterns. The neurons responded to ipsilateral light stimulation with an increase in firing rate and to the α2-receptor agonist clonidine with significantly decreased firing rates. In vivo electrochemical studies demonstrated reproducible noradrenergic overflow after local application of potassium. Immunohistochemical evaluation of the brainstem transplants showed an abundance of tyrosine hydroxylase-positive neurons and neurites in all transplants and a dense network of neurofilament-, synapsin-, and glial fibrillary acidic protein-positive profiles throughout the grafts. Taken together, the present physiological and histochemical data indicate that it is possible to obtain transplants containing a specific monoaminergic population within the brainstem from human fetal fragments and to maintain these transplants in oculo in athymic nude rats for at least 15 months, during which time noradrenergic neurons develop.
|Number of pages||11|
|State||Published - Oct 1992|
Bibliographical noteFunding Information:
Thanks are due to Ms. Ludmila Mackerlova for expert technical help. This paper was supported by the Swedish Medical Research Council, Grants 8650,8868, and 9917, Magnus Bergvall, Lars Hierta, and Karolinska Institute Foundations, as well as USPHS Grants AGO6434 and AG00441.
ASJC Scopus subject areas
- Developmental Neuroscience