Influence of isoflurane exposure in pregnant rats on the learning and memory of offsprings

Abstract

BackgroundAbout 2% of pregnant women receive non-obstetric surgery under general anesthesia each year. During pregnancy, general anesthetics may affect brain development of the fetus. This study aimed to investigate safe dosage range of isoflurane.MethodsForty-eight SpragueDawley (SD) pregnant rats were randomly divided into 3 groups and inhaled 1.3% isoflurane (the Iso1 group), 2.0% isoflurane (the Iso2 group) and 50% O2 alone (the control group) for 3 h, respectively. Their offsprings were subjected to Morris water maze at day 28 and day 90 after birth to evaluate learning and memory. The expression of cAMP-response element binding protein (CREB) and phosphorylated cAMP-response element binding protein (p-CREB) was detected in the hippocampus dentate gyrus.ResultsLess offsprings of Iso2 group were able to cross the platform than that of the control group (P < 0.05). Accordingly, the Iso2 offsprings expressed p-CREB mainly in the subgranular zone in contrast to the whole granular cell layer of hippocampus dentate gyrus as detected in the Iso1 and control offsprings; the expression level of pCREB was also lower in the Iso2 than Iso1 or control offsprings (P < 0.05).ConclusionInhalation of isoflurane at 1.3% during pregnancy has no significant influence on learning and memory of the offspring; exposure to isoflurane at 2.0% causes damage to spatial memory associated with inhibition of CREB phosphorylation in the granular cell layer of hippocampus dentate gyrus.

Age-related murine hippocampal CA1 laminae oxidative stress measured in vivo by QUEnch-assiSTed (QUEST) MRI: impact of isoflurane anesthesia

“…The results of this study, and those from the literature, highlight the need for caution when using isoflurane which, when used repeatedly, is not benign as is often assumed (Bajwa et al 2018;Crystal et al 2012;Huang et al 2018;Li et al 2018;Lin and Zuo 2011;Ni et al 2017;Paasonen et al 2018;Wu et al 2015;Zhang et al 2018).…”

Subsequent maternal sleep deprivation aggravates cognitive impairment by modulating hippocampal neuroinflammatory responses and synaptic function in maternal isoflurane‐exposed offspring mice

“…The prenatal period is critical for brain development, and, at this epoch, the embryo is especially vulnerable to environmental interference. Clinical and preclinical studies have documented that maternal anesthetics exposure can result in abnormal brain development in offspring (Huang et al., 2018 ; Reitman & Flood, 2011). Concurrently, pregnant women can also suffer from sleep disorders owing to alterations in physiology and anatomy that occur during pregnancy (Bacaro et al., 2020 ; Miller et al., 2020 ).…”

“…Preclinical studies have also shown that isoflurane exposure during pregnancy can lead to offspring cognitive dysfunction (Fan et al., 2022 ). Rodent studies have documented that fetal exposure to general anesthesia induces long‐term neurobehavioral dysfunctions, such as cognitive impairment (Huang et al., 2018 ; Zuo, Li et al., 2020 ).…”

Magnetic resonance imaging for early pregnancy diagnosis in the laboratory rat

“…34 Other anaesthetic agents, such as isoflurane or tribromoethanol, have been proposed as safer alternative anaesthetic agents with regard to embryo development in survival rodent toxicity models. 33,35,36 For procedures lasting more than around 10 minutes, provision of an external form of heat or wrapping of the animal or its extremities with an insulator, such as a plastic wrap, is advised in order to maintain normal core body temperature. 32,35…”