Send to

Choose Destination
Exp Neurol. 2014 Sep;259:57-63. doi: 10.1016/j.expneurol.2014.04.004. Epub 2014 Apr 13.

The neuroanatomy of sexual dimorphism in opioid analgesia.

Author information

Pain Management Research Area, United States Army Institute of Surgical Research, Fort Sam Houston, TX 78234, United States.
Neuroscience Institute, Georgia State University, Atlanta, GA 30303, United States. Electronic address:


The influence of sex has been neglected in clinical studies on pain and analgesia, with the vast majority of research conducted exclusively in males. However, both preclinical and clinical studies indicate that males and females differ in both the anatomical and physiological composition of central nervous system circuits that are involved in pain processing and analgesia. These differences influence not only the response to noxious stimuli, but also the ability of pharmacological agents to modify this response. Morphine is the most widely prescribed opiate for the alleviation of persistent pain in the clinic; however, it is becoming increasingly clear that morphine is less potent in women compared to men. This review highlights recent research identifying neuroanatomical and physiological dimorphisms underlying sex differences in pain and opioid analgesia, focusing on the endogenous descending pain modulatory circuit.


Morphine; Mu opioid receptor; Pain; Periaqueductal gray

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center