The Role of the Periaqueductal Gray in the Modulation of Pain in Males and Females: Are the Anatomy and Physiology Really that Different?

Figure 3

(a) Mean number of PAG cells retrogradely labeled from the RVM across the rostrocaudal axis in males (left) and females (right). (b) Percentage of Fos-positive neurons that were retrogradely labeled from the RVM in males (left) and females (right) following twenty-four hours of inflammation. (c) Average of the percentage of AR (left) and ER𝛼 (right) receptor-expressing PAG cells retrogradely labeled from the RVM. (d) Percentage of Fos-positive neurons that were retrogradely labeled from the RVM in males (left) and females (right) following twenty-four hours of inflammation and one hour of morphine (5 mg/kg).