Astrocytes rather than neurones mediate interleukin-1β dependent nitric oxide and superoxide radical release in primary hypothalamic rat cell cultures

Abstract

The cellular sources of nitric oxide in the hypothalamus are thought to be ‘NOergic’ neurones. Using free radical electrochemical sensors we investigated nitric oxide and superoxide radical release in primary hypothalamic cell cultures. We present evidence that under interleukin-1β (IL-1β) stimulation hypothalamic astrocytes rather than neurones release nitric oxide. Under l-arginine deprivation and IL-1β stimulation a concentration-dependent release of superoxide was also observed, which was inhibited in the presence of nitric oxide synthase inhibitor nitro- l-arginine-methyl-ester. These findings support the hypothesis that the balance between nitric oxide and superoxide may be of vital importance in hypothalamic pathophysiology.