Estrous cycle-dependent modulation of in vivo microvascular dysfunction after nanomaterial inhalation

Publication date: June 2018 Source:Reproductive Toxicology, Volume 78 Author(s): P.A. Stapleton, C.R. McBride, J. Yi, A.B. Abukabda, T.R. Nurkiewicz Preconceptive health encompasses male and female reproductive capability. In females, this takes into account each of the stages of the estrous cycle. Microvascular reactivity varies throughout the estrous cycle in response to hormonal changes and in preparation for pregnancy. Microvascular alterations in response to engineered nanomaterial (ENM) exposure have been described within 24-h of inhalation; however, the impact upon the uterine vasculature at differing estrous stages and at late-stage pregnancy is unclear. Female Sprague Dawley (SD) rats (virgin and late stage pregnancy [GD 19]) were exposed to nano-TiO aerosols (173.2 ± 6.4 nm, 10.2 ± 0.46 mg/m3, 5 h) 24-h prior to experimentation leading to a single calculated deposition of 42.2 ± 1.9 μg nano- TiO2 (exposed) or 0 μg (control). Animals were anesthetized, estrous status verified, and prepared for in situ assessment of leukocyte trafficking and vascular function by means of intravital microscopy, Uterine basal arteriolar reactivity was stimulated using iontophoretically applied chemicals: acetylcholine (ACh, 0.025 M; 20, 40, 100, 200 nA), sodium nitroprusside (SNP, 0.05 M; 20, 40, 100 nA), phenylephrine (PE, 0.05 M; 20, 40, 100 nA). Finally, adenosine (ADO, 10−4 M) was superfused over the tissue to identify maximum diamet...
Source: Reproductive Toxicology - Category: Toxicology Source Type: research