Sulprostone-Induced Gastric Dysrhythmia in the Ferret: Conventional and Advanced Analytical Approaches

Zengbing Lu; Yu Zhou; Longlong Tu; Sze Wa Chan; Man P Ngan; Dexuan Cui; Yuen Hang Julia Liu; Ianto Bosheng Huang; Jeng S C Kung; Chung Man Jessica Hui; John A Rudd

doi:10.3389/fphys.2020.583082

Sulprostone-Induced Gastric Dysrhythmia in the Ferret: Conventional and Advanced Analytical Approaches

Front Physiol. 2021 Jan 8:11:583082. doi: 10.3389/fphys.2020.583082. eCollection 2020.

Authors

Zengbing Lu^{1

2}, Yu Zhou³, Longlong Tu¹, Sze Wa Chan², Man P Ngan¹, Dexuan Cui¹, Yuen Hang Julia Liu¹, Ianto Bosheng Huang¹, Jeng S C Kung¹, Chung Man Jessica Hui¹, John A Rudd^{1

4}

Affiliations

¹ School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
² School of Health Sciences, Caritas Institute of Higher Education, Tseung Kwan O New Town, Hong Kong.
³ Institute of Future Cities, The Chinese University of Hong Kong, Shatin, Hong Kong.
⁴ Laboratory Animal Services Centre, The Chinese University of Hong Kong, Shatin, Hong Kong.

Abstract

Nausea and emesis resulting from disease or drug treatment may be associated with disrupted gastric myoelectric activity (GMA). Conventional analytical techniques can determine the relative degrees of brady-, normo-, and tachygastric power, but lose information relative to the basic slow wave shape. The aim of the present study was to investigate the application of advanced analytical techniques in the analysis of disrupted GMA recorded after administration of sulprostone, a prostaglandin E₃ _/ ₁ agonist, in ferrets. Ferrets were implanted with radiotelemetry devices to record GMA, blood pressure, heart rate (HR) and core body temperature 1 week before the administration of sulprostone (30 μg/kg) or vehicle (saline, 0.5 mL/kg). GMA was initially analyzed using fast Fourier transformations (FFTs) and a conventional power partitioning. Detrended fluctuation analysis (DFA) was also applied to the GMA recordings to reveal information relative to the fluctuation of signals around local trends. Sample entropy (SampEn) analysis was used for examining the regularity of signals. Conventional signal processing techniques revealed that sulprostone increased the dominant frequency (DF) of slow waves, with an increase in the percentage power of the tachygastric range and a decrease in the percentage power of the normogastric range. DFA revealed that sulprostone decreased the fluctuation function, indicative of a loss of the variability of GMA fluctuations around local trends. Sulprostone increased SampEn values, indicating a loss of regularity in the GMA data. Behaviorally, sulprostone induced emesis and caused defecation. It also increased blood pressure and elevated HR, with an associated decrease in HR variability (HRV). Further analysis of HRV revealed a decrease in both low-frequency (LF) and high-frequency (HF) components, with an overall increase in the LF/HF ratio. Sulprostone did not affect core body temperature. In conclusion, DFA and SampEn permit a detailed analysis of GMA, which is necessary to understand the action of sulprostone to modulate gastric function. The action to decrease HRV and increase the LF/HF ratio may be consistent with a shift toward sympathetic nervous system dominance, commonly seen during nausea.

Keywords: detrended fluctuation analysis; entropy; ferret; gastric myoelectric activity; running spectrum analysis; sulprostone.