D. Petite et Mc. Calvet, MORPHOMETRIC CHARACTERISTICS OF CRYOPRESERVED MESENCEPHALIC DOPAMINE NEURONS IN CULTURE, Brain research, 769(1), 1997, pp. 1-12
Blocks of embryonic rat mesencephalon were freeze-stored for 1-2 years
in liquid nitrogen at -196 degrees C with 7.5% dimethyl sulfoxide (DM
SO) as cryoprotectant. After thawing, pooled mesencephalic tissues wer
e mechanically dissociated. The cells, plated at two different densiti
es (4.10(5) and 2.10(5)/cm(2)) were cultured in a serum-supplemented m
edium for at least 2 weeks before immunocytochemical staining with hig
hly specific antidopamine (DA) antibodies. The cryopreserved DA-immuno
reactive (IR) neurons were compared, by means of computerized morphome
try, to the fresh ones plated at the same densities. A separate analys
is of the dendritic and axonal morphometric parameters revealed that t
he cryopreserved DA-IR cells, whatever the experimental conditions, ha
d significantly larger dendritic fields and, less significantly, large
r axonal fields than their fresh counterparts. A principal component a
nalysis, mainly based on the dendritic morphometric parameters, allowe
d to individualize only two populations (cryopreserved and fresh) amon
g the four,stoups studied. These findings underline the role of dendri
tes as potential sites of release and/or re-uptake of dopamine and the
ir possible implications in functionally effective cryopreserved nigra
l grafts. (C) 1997 Elsevier Science B.V.