Food or water deprivation modulate nitric oxide synthase (NOS) activity and gene expression in rat hypothalamic neurones: Correlation with neurosecretory activity?

Abstract

Nitric oxide (NO) is produced by the enzyme NO synthase (NOS) and may be involved in the regulation of nutrient and endocrine homeostasis via actions on neurones of the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei. The effects of water deprivation or food deprivation for 4 days on the abundance of messenger RNA encoding NOS in these nuclei in rats were examined using in situ hybridization. Water deprivation markedly increased the abundance of NOS mRNA in both the SON and PVN (225 ± 11% of control, P < 0.05 and 261 ± 34% of control, P < 0.01 respectively). NOS mRNA abundance also appeared to be increased in magnocellular accessory nuclei. Food deprivation decreased NOS mRNA ..