Nimodipine accelerates the postnatal development of parvalbumin and S-100β immunoreactivity in the rat brain

Abstract

The effects of chronic maternal perinatal nimodipine treatment on the immunocytochemical distribution of the Ca(2+)-binding proteins parvalbumin (PV) and S-100 beta in neocortex and hippocampus were studied at the age of postnatal day (PD) 5, 7, 10, 14 and 20. The Ca2+ antagonist nimodipine (1000 ppm BAY e 9736 in daily food) was administered to pregnant rats starting at postconceptual day 11. The expression of PV exemplified in layer V of parietal and retrosplenial cortex and in all hippocampal layers of CA1 and CA3 was enhanced by more than two-fold in the offspring of nimodipine-treated dams at PD 10 compared with placebo-treated animals. The difference was no longer present at PD 14 and 20. Nimodipine administration also significantly increased the number of S-100 beta-immunopositive glial cells in upper neocortical layers I-III at PD 5 and 7. Again, the difference between nimodipine and placebo-treated animals disappeared after PD 10. The data indicate an accelerated development of PV and S-100 immunoreactivity in the postnatal forebrain as a result of perinatal blockade of the L-type Ca2+ current.

Calcium-Modulated Proteins Change Their Immunoreactivity in the Presence of Ca2+: A Study of Antibody Recognition in a Dot Immunoassay for Calmodulin, Calcineurin (β-subunit), and S100B

“…Less than 0.2 mg of the smaller subunits of the E. coli ATPase was detected REFERENCES (Fig. 2, II); this amount could be lowered at least by a factor of 20, using less protein, but increased exposure 1 We were able to confirm that long transfer times are 3. Whitehead, T. P., Thorpe, G. H. G., Carter, T. J. N., Groucutt, necessary and that low transfer efficiency ensues, when pointed out previously (2).…”

“…(2,3). In this work we investigated the tection can be carried out with any customary detection influence of Ca 2/ on the immunoreactivity of three system with blots from silver-stained proteins; proteins other EF-hand proteins also found in brain: calmodustained with Coomassie blue must be detected by a nonchromogenic method, e.g., by ECL.…”

Distribution of the calcium-binding proteins parvalbumin and calretinin in the auditory brainstem of adult and developing rats

“…Heavily CB-ir neurons can be found in neonates and PV-ir does not appear before P5. In addition, within the developing rat cortex, CR expression can he observed very early (at E12-El4; Weisenhorn et al, 19941, followed by CB (E14-PO; Sanchez et al, 1992) and PV, which does not appear before P6 (Sanchez et al, 1992;Buwalda et al, 1994). All these data support the idea that CR and CB may often be associated with very early, as well as later, aspects of synapse formation, respectively, whereas PV may be associated with the mature system.…”

Relationship of the time of origin and death of neurons in rat somatosensory cortex: Barrel versus septal cortex and projection versus local circuit neurons

“…These proteins likely are crucial for the distinctive tonic electrophysiological activity (e.g., Connors et al, 1982;McCormick et al, 1985) and chronically high metabolic rates (McCasland et al, 1993) maintained by cortical local circuit neurons. Note that rats prenatally exposed to nimodopine have greater numbers of parvalbumin-immunoreactive local circuit neurons (Buwalda et al, 1993). These data are particularly interesting since nimodopine acts as a neuroprotective agent by blocking calcium channels.…”