Altered nitric oxide synthase and PKC activities in cerebellum of gamma-irradiated neonatal rats.
In this study, we show that one single dose of gamma-irradiation at birth induces an inhibition of the cerebellar calcium dependent nitric oxide synthase (NOS) activity, probably correlated to the motor abnormalities and the disarrangement in the cerebellar cytoarchitecture observed in adult rats. This decrease in calcium dependent NOS activity could be associated with an increased protein kinase C (PKC) activity. PKC inhibition partially restores calcium dependent NOS activity, indicating that PKC activity could be negatively modulating the catalytic activity of calcium dependent NOS. These findings suggest that a decrease in nitric oxide (NO) production and the related increase in PKC activity could be intracellular events that participate in the onset of motor and cerebellar abnormalities induced by postnatal gamma-irradiation at early stages of life.
Zorrilla Zubilete
María A
MA
1a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires (UBA), 2155 Paraguay St. Piso 15, (1121) Ciudad de Buenos Aires, Argentina. zorrilla@fmed.uba.ar
Ríos
Hugo
H
Silberman
Dafne Magali
DM
Guelman
Laura Ruth
LR
Ricatti
María Jimena
MJ
Genaro
Ana María
AM
Zieher
Luis María
LM
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D064026:Calbindins; D002118:Calcium / Q000378:metabolism; D002531:Cerebellum / Q000201:enzymology* / Q000473:pathology / Q000528:radiation effects*; D005260:Female; D005684:Gait / Q000528:radiation effects; D005720:Gamma Rays; D008297:Male; D009474:Neurons / Q000201:enzymology / Q000473:pathology / Q000528:radiation effects; D019001:Nitric Oxide Synthase / Q000528:radiation effects*; D011493:Protein Kinase C / Q000528:radiation effects*; D011833:Radiation Injuries, Experimental / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar; D064030:S100 Calcium Binding Protein G / Q000528:radiation effects; D015398:Signal Transduction / Q000528:radiation effects; D013997:Time Factors
D064026:Calbindins; D064030:S100 Calcium Binding Protein G; D019001:Nitric Oxide Synthase; D011493:Protein Kinase C; D002118:Calcium