Since the proposal that nitric oxide acts as an intercellular signalling molecule in the nervous system, a large number of studies have been carried out to determine its functions in neural tissue. In this study, neuronal nitric oxide synthase using the highly specific polyclonal nature of an antibody is observed mainly in laminae I-IIi, lamina X and in the intermediolateral cell column of the thoraco-lumbar spinal cord. The distribution of neuronal nitric oxide synthase was confirmed and extended the work done in previous studies. Distinct concentrations of neuronal nitric oxide synthase expressing small to medium sized neurones were seen in two bands: one in lamina I and the second in lamina IIi. It is suggested that these neurones are probably Islet type interneurones and could be inhibitory interneurones. Therefore, based on the observations of nitric oxide synthase containing neurones in laminae I-II, laminae IV-V and lamina X, it suggests that nitric oxide is involved in nociception.

Since the proposal that nitric oxide acts as an intercellular signalling molecule in the nervous system, a large number of studies have been carried out to determine its functions in neural tissue. In this study, neuronal nitric oxide synthase using the highly specific polyclonal nature of an antibody is observed mainly in laminae I-IIi, lamina X and in the intermediolateral cell column of the thoraco-lumbar spinal cord. The distribution of neuronal nitric oxide synthase was confirmed and extended the work done in previous studies. Distinct concentrations of neuronal nitric oxide synthase expressing small to medium sized neurones were seen in two bands: one in lamina I and the second in lamina IIi. It is suggested that these neurones are probably Islet type interneurones and could be inhibitory interneurones. Therefore, based on the observations of nitric oxide synthase containing neurones in laminae I-II, laminae IV-V and lamina X, it suggests that nitric oxide is involved in nociception.