DEVELOPMENTAL PATTERN OF NADPH-DIAPHORASE ACTIVITY AND NITRIC OXIDE-STIMULATED CGMP IMMUNOREACTIVITY IN THE FRONTAL RAT CORTEX AND ITS ROLEIN FUNCTIONAL RECOVERY FROM ASPIRATION LESIONS

The present study was undertaken to (1) explore the cortical nitric ox ide (NO)-system during postnatal development and (2) to see whether or not the NO-system reacts differentially after neonatal and adult lesi ons of the medial prefrontal cortex. Three aspects of the NO-system we re studied, i.e., NADPH-diaphorase (NADPH-d) activity; sodium nitropru sside (SNP)- and N-methyl-D-aspartate (NMDA)-stimulated cGMP-immunorea ctivity (cGMP-IR). It was shown that: (1) the development of NADPH-d a ctivity containing cells is continued in the period from P6 until P21; (2) during the same period, large developmental changes take place in basal, and SNP- or NMDA-stimulated cGMP-IR in the cortex. These chang es are regionally specific and follow the general cortical development al pattern; and (3) aspiration lesions do not induce major changes in the distribution of NADPH-d activity or cGMP-IR, either basal, SNP- or NMDA-stimulated.