Premium
Heart Rate Variability Measures Positively Correlate with Gastric Motility in Freely‐Moving Adult Rats
Author(s) -
Meister Alissa L,
Jiang Yanyan,
Doheny Kim K,
Travagli R. Alberto
Publication year - 2019
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.2019.33.1_supplement.763.5
Subject(s) - heart rate variability , vagal tone , medicine , antrum , dorsal motor nucleus , motility , heart rate , vagus nerve , endocrinology , gastric distension , stomach , cardiology , blood pressure , stimulation , biology , genetics
Studies have shown that a decrease in parasympathetic tone to the GI tract is associated with increasing adverse outcomes associated with inflammation and sepsis. Currently, there are no non‐invasive methods to measure vagal tone to the GI tract. Conversely, cardiac vagal tone can be monitored non‐invasively via measurement of the high frequency power spectrum of heart rate variability (HF‐HRV). Although these parasympathetic outputs arise from distinct brainstem nuclei (cardiac from nucleus ambiguus, GI from dorsal motor nucleus of the vagus), it is unclear whether these efferent outputs are regulated in parallel. The aim of our study, thus, was to test the hypothesis that cardiac vagal tone is a surrogate marker for gastric motility by demonstrating that HF‐HRV is positively correlated with gastric motility and can be altered by pharmacological interventions targeted to the GI tract. Adult age‐matched male and female Sprague‐Dawley rats were implanted with a miniaturized strain gauge on the gastric antrum and 2‐pole electrocardiogram electrodes to collect simultaneous antral motility and HRV recordings. After a 2–3 day recovery period, rats were fasted from 8am–8pm, and daily recordings of gastric motility and HRV were performed. During these recordings, male rats received intraperitoneal injections of saline (1ml), cholecystokinin (CCK; 5nmoles), or ghrelin (100 pmoles/kg). Female rats underwent daily vaginal swabs to determine the stage in estrus cycle. Male rats displayed a significant positive correlation between HF‐HRV and gastric motility (N=8; r 2 =0.43, p<0.05) that was maintained following the decrease in antral motility induced by CCK (N=7; r 2 =0.046, p<0.05). Conversely, administration of ghrelin, despite inducing a significant increase in antral motility, did not display a significant correlation with HF‐HRV (N=6; r 2 =0.047, p>0.05). There were no significant changes in heart rate after any of the treatments. Female rats showed a significant correlation between HF‐HRV and gastric motility during metestrus and diestrus (N=4; r 2 =0.062, p<0.05); however this correlation was absent during proestrus and estrus (N=4; r 2 =0.003, p>0.05). Our data indicate that HF‐HRV positively correlates with gastric motility in males at baseline or following pharmacological interventions known to affect vagal tone and during periods of low estrus in female rats. Conversely, increased estradiol levels disrupt the correlation between HF‐HRV and antral motility. Support or Funding Information NIH grant DK99350 to R.A.T. & K.K.D. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .