Effects of Peritoneal Sepsis on Rat Central Osmoregulatory Neurons Mediating Thirst and Vasopressin Release.

Abstract

Sepsis is a life-threatening condition caused by the systemic inflammatory response to bacterial infection. Although the early phase of sepsis features impaired thirst and enhanced vasopressin release, the basis for these defects is unknown. Here, we show that cecal ligation and puncture (CLP) in rats impairs the osmoresponsiveness of neurons in the organum vasculosum lamina terminalis (OVLT; which drives thirst) and attenuates that of neurosecretory neurons in the supraoptic nucleus (SON; which secrete oxytocin and vasopressin). Notably, we found that OVLT neurons are hyperpolarized and electrically silenced. In contrast, CLP increased the proportion of SON neurons displaying spontaneous electrical activity. Therefore, CLP affects the properties of osmoregulatory neurons in a manner that can affect systemic osmoregulation.