Tissue- and Development-specific Expression of Multiple Alternatively Spliced Transcripts of Rat Neuronal Nitric Oxide Synthase

Nitric oxide (NO) functions as an intercellular messenger and mediates numerous biological functions. Among the three isoforms of NO synthase that produce NO, the ubiqui-tously expressed neuronal NO synthase (nNOS) is responsi-ble for a large part of NO production, yet its regulation is poorly understood. Recent reports of two alternative splice-forms of nNOS in the mouse and in man have raised the possibility of spatial and temporal modulation of expres-sion. This study demonstrates the existence of at least three transcripts of the rat nNOS gene designated nNOSa, nNOSb