Vol 63, No 4 (2004)
Original article
Published online: 2004-09-16
Parvalbumin containing neurons of the piriform cortex in open field stress - a developmental study in the rat
Folia Morphol 2004;63(4):367-372.
Abstract
In our study we used c-Fos protein (as a marker of cellular activity) to identify
whether cells containing parvalbumin (PV) in the piriform cortex (PC) are engaged
in the response to stress stimulation and to discover how this expression
changes during maturation. The material consisted of Wistar rats of postnatal
(P) ages between 0 and 120 days divided into 9 groups: P0, P4, P7, P10, P14,
P21, P30, P90, P120. Each group consisted of 5 experimental and 3 control
animals. Rats of the experimental groups were exposed to the "open field test"
throughout 10 minutes. The control animals were kept in a home cage. Our
results showed that c-Fos activity in the open field test was observed in layers II
and III of PC after birth. It then increased and stabilised on P30. In the second
week of life PV-positive cells were also observed in those layers. These achieved
maturity in the 4th week of life. After this time basket-like structures appeared
but the level of PV/c-Fos co-localisation was low. Only small differences were
observed between the anterior and posterior parts of PC. In the anterior part
a higher number of PV-positive neurons, neuropil threads, and basket-like structures
and a larger degree of PV/c-Fos co-localisation were observed. Our results
suggested that during maturation PV cells are not directly activated in response
to stress stimuli but PV neurons via their numerous endings influence the activation
of c-Fos-positive cells predominantly in the anterior part of PC.
Keywords: c-Fosmaturationopen field test