ARE PHYSIOLOGICAL-EFFECTS OF SLEEP-DEPRIVATION IN THE RAT MEDIATED BYBACTERIAL INVASION

Recent reports have indicated that rats subjected to total sleep depri vation (TSD) by the disk-overwater method and sacrificed when death ap peared imminent showed aerobic bacteria in their blood. Yoked control rats did not. Extrapolating from these results, it has been suggested that the late body temperature declines and eventual deaths of TSD rat s are caused by septicemia, and that other, earlier-appearing effects of TSD-including weight loss, increased energy expenditure, and regula tion of temperature at a higher level-might be mediated by impaired ho st defenses against bacterial invasion. Three measures of aerobic bact erial invasion were used to evaluate these hypotheses: bacteremia, bac terial colonization in major organs of filtration (liver, kidney, and mesenteric lymph nodes), and adherence of bacteria to the cecal wall. Experiment 1 showed nonsignificant trends toward more bacterial invasi on in 4-day TSD rats compared to yoked control rats and no relationshi p between the bacterial indicators and the early TSD effects. Experime nt 2 showed that the elimination of aerobic bacterial infection by ant ibiotic treatment did not prevent the early TSD effects in 4-day TSD r ats. Experiment 3 showed that the elimination of aerobic bacterial inv asion in TSD rats did not eliminate the late temperature decline or th e progression toward death. The results showed no significant evidence of aerobic bacterial invasion early in TSD and no indication that: th e major effects of TSD were dependent upon aerobic bacterial invasion.