Hydrogen Sulphide Influences the Excitability of Neurons in the Paraventricular Nucleus of the Hypothalamus

Abstract

Hydrogen sulphide (H2S) has been observed as having a protective role against gastro‐intestinal inflammation. H2S‐catalyzing enzymes are expressed in the paraventricular nucleus of the hypothalamus (PVN). Previous findings suggest that, if stimulated, the PVN can produce inflammatory responses in the GI tract. To understand the effects of H2S in the PVN, we examined the effects of the H2S donor, sodium hydrogen sulphide (NaHS) on the excitability of PVN neurons. Whole‐cell current clamp recordings from rat PVN neurons in slice preparations were performed. Bath application of 50 μM NaHS influenced 90% (9/10) of cells tested within approximately 45s. of administration. 100% of the responsive cells exhibited a hyperpolarizing response (n=9, −15.42 ± 2.55mV). Of these cells, 89% returned to baseline after approximately 15 mins. Four these neurons were identified as parvocellular neurons and 5 were identified as magnocellular neurons, both displayed similar responses to NaHS. These findings shed light on the role that NaHS plays in the PVN to modify the membrane potential of neurons and in turn, may affect the possible pathways associated with the PVN that are involved in inflammatory effects.Support CIHR