The cerebral mechanism underlying the acupoints with specific effect for gallbladder stone disease: protocol for a randomized controlled task-fMRI trial

Background As it has been recorded in ancient Chinese classics, Yanglingquan (GB34) and Dannangxue (EX-LE6) are two important acupoints that can regulate the function of the gallbladder. Acupuncture at these two acupoints is considered particularly effective for gallbladder disease treatment, especially for alleviating gallbladder stone disease (GSD) symptoms that can be aggravated after intaking high-fat food. However, the superior effect between the two acupoints still needs to be further explored, as well as the underlying central mechanism has never been investigated to date. Methods and design Ninety participants diagnosed with GSD will be randomly divided into group A (acupuncture at GB34), group B (acupuncture at EX-LE6), and group C (acupuncture at non-acupoint) in a ratio of 1:1:1. All of them will receive a 30-min acupuncture treatment with fatty-food cues being presented before and after acupuncture. During the task, participants will be scanned by MRI and required to rate their desire for high-/low-fat food with an 11-point Likert scale. Additionally, the participants’ pain/discomfort sensation will be evaluated using the Numeric Rating Scale (NRS) at four timepoints, including before the 1st task fMRI scan, before and after acupuncture, and after the 2nd task fMRI scan. For both behavior and fMRI data, the ANOVA analysis will be conducted among three groups to testify the immediate effect of GB34 and EX-LE6. The post hoc t-test will be employed to further explore the superiority between acupuncture with GB34 and EX-LE6. Furthermore, correlation analyses will be conducted to investigate a possible correlation between neural changes and clinical data. Discussion In comparison to the non-acupoint, the results will firstly explore the superior effect between acupuncture with GB34 and EX-LE6 on GSD patients by observing their behavioral and neural response change to fatty-food cue, and then to investigate the underlying central mechanism. Trial registration Chinese Clinical Trial Registry ChiCTR2000034368. Registered on 3 July 2020.