---
title: What biological mechanism might cause premenstrual syndrome and could a herbal medicine help?
description: In rats with stress-like PMS symptoms, a protein called MOR may play a role, and a herbal medicine (Shu-Yu capsule) may help by reducing this protein. This is
url: https://niyora.com/research/papers/roles-of-the-opioid-receptor-and-its-related-signaling-pathways-in-the-2017/
---

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- What biological mechanism might cause premenstrual syndrome and could a herbal medicine help?

Non-randomised trial, 2017

# What biological mechanism might cause premenstrual syndrome and could a herbal medicine help?

In rats with stress-like PMS symptoms, a protein called MOR may play a role, and a herbal medicine (Shu-Yu capsule) may help by reducing this protein. This is rat research, not human research.

 Early or limited evidence

Rats with chronic stress-induced PMS-like symptoms

## What they did

Researchers created PMS-like symptoms in rats using chronic stress. They measured a protein called MOR in rat brains and tested whether a herbal medicine (Shu-Yu capsule) changed MOR levels and related brain chemicals.

## What they found

Stressed rats had high levels of MOR protein. The Shu-Yu capsule reduced MOR expression and reversed stress-related changes in brain chemicals, including BDNF and cAMP.

## What it means for you

This animal study suggests one possible biological mechanism in PMS and that a herbal medicine might help by affecting this mechanism. However, this is rat research, not human research, so we cannot yet know if it applies to women with PMS.

## About the study

Original title Roles of the µ-opioid receptor and its related signaling pathways in the pathogenesis of premenstrual syndrome liver-qi stagnation Authors Song C, Xue L Journal Experimental and therapeutic medicine Year 2017 Study design Non-randomised trial What was tested Shu-Yu capsule (herbal medicine) vs. control Open access Yes Read the paper [doi.org/10.3892/etm.2017.4374](https://doi.org/10.3892/etm.2017.4374)

## Topics

[Premenstrual syndrome (PMS)](https://niyora.com/research/topics/condition-pms/)[Stigma, attitudes and culture](https://niyora.com/research/topics/life-area-stigma-culture/)

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