Interactions of carotid sinus or aortic input with emetic signals from gastric afferents and vestibular system

Measuring the nausea-to-emesis continuum in non-human animals: refocusing on gastrointestinal vagal signaling

“…In humans and preclinical models with an emetic reflex, application of gastric stretch or toxins to the gastric lumen produce nausea and emesis (Blackshaw et al 1987; Ladabaum et al 1998; Araya et al 2001; Olivares et al 2001; Hu et al 2007; Uchino et al 2008). Preclinical research using intragastric CuSO 4 (a mucosal irritant) has provided significant insights into this GI pathway: 1) CuSO 4 stimulates release of 5-HT from enteroendocrine cells in ferrets; 2) intragastric CuSO 4 increases vagal afferent activity in ferrets; 3) abdominal vagotomy markedly inhibits intragastric CuSO 4 -induced emesis in dogs, ferrets, and musk shrews; and, 4) systemic antagonism of 5-HT 4 receptors blocks CuSO 4 -induced emesis in dogs, ferrets, and musk shrews (Bhandari and Andrews 1991; Makale and King 1992; Fukui et al 1994; Endo et al 1995; Reynolds et al 1995; Hu et al 2007).…”

Impact of electrical stimulation of the stomach on gastric distension‐induced emesis in the musk shrew

“…The primary goal of this project was to assess the detailed physiological effects of GES on gastric distension‐induced emesis using an established emetic test system: an in vivo musk shrew preparation . We tested the effects of GES pulse duration (0.3, 1, 5, and 10 ms), current amplitude (0.5, 1, and 2 mA), pulse frequency (8, 15, 30, and 60 Hz), and electrode placement (antrum, body, and fundus).…”

“…Firstly, we used a limited range of stimulation parameters, with inclusion of only 0.5–2 mA #bib8–60 Hz, and 0.3–10 ms pulse duration. Secondly, we used only one emetic stimulus, vagal, and there are at least three additional routes for emetic stimulation: vestibular, area postrema, and forebrain (review). Excessive gastric distension can also provide nociceptive input to the spinal cord; and thus, is not a purely vagal stimulus.…”

“…Core temperature was monitored with a rectal probe and regulated to 37 °C using a controlled heating pad (CWE; Ardmore, PA, USA). A tracheal tube was installed to monitor intra‐tracheal airway pressure (CWE air pressure transducer), which was used to record respiration rate and the occurrence of emetic episodes, i.e., large, high‐frequency changes in thoracic pressure indicate retching . A right carotid artery catheter was used to monitor blood pressure using a fluid filled catheter (Kent Scientific; Torrington, CT, USA).…”

“…[17][18][19][20][21][22][23][24][25] In addition, the musk shrew's gastrointestinal physiology is similar to humans with respect to motility responses and a functional motilin system, which is lacking in rodents. 26,27 In the current studies, we used a urethane-anesthetized musk shrew preparation in which physiological responses can be recorded in detail, [28][29][30] including emesis (by monitoring intra-tracheal pressure and esophageal contractions [31][32][33] ), respiration rate, heart rate variability, blood pressure, and gastrointestinal electromyograms. Gastric distention, with a balloon, was used as the emetic stimulus.…”