Premium
Synergistic effect of spexin and progesterone on pain sensitivity attenuation in ovariectomized rats
Author(s) -
Moazen Parisa,
Taherianfard Mahnaz,
Ahmadi Soleimani Mohammad,
Norozpor Mitra
Publication year - 2018
Publication title -
clinical and experimental pharmacology and physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 103
eISSN - 1440-1681
pISSN - 0305-1870
DOI - 10.1111/1440-1681.12862
Subject(s) - ovariectomized rat , medicine , endocrinology , subcutaneous injection , nociception , hippocampal formation , chemistry , anesthesia , estrogen , receptor
Summary Spexin is a central modulator of nociception. The aim of the present study was to investigate the effect of intra‐hippocampal CA 3 ( IHCA 3) injection of spexin and spexin‐progesterone co‐administration on pain sensitivity in ovariectomized rat. Thirty‐five adult female rats were divided into five groups. Sham: the animals received injection of 0.5 μL ACSF by IHCA 3. Experiments 1 and 2: the animals received injection of 0.5 μL of spexin bilaterally (10 and 30 nmol/rat respectively). Experiments 3 and 4: the animals received injection of 0.5 μL of spexin bilaterally (10 and 30 nmol/rat respectively) + subcutaneous (s.c.) injection of progesterone (5 mg/kg). Ovariectomy was performed in all groups to eliminate the effects of cyclic changes in the female rats. The formalin test (formalin 2.5%) was performed following the administration of spexin and progesterone. Results showed that bilateral injection of spexin in IHCA 3 at both concentrations a significant ( P < .05) decrease in the pain sensitivity in the two phases of formalin test. Similarly, the bilateral injection of spexin in IHCA 3 at both concentrations following the s.c. injection of progesterone significantly ( P < .05) decreases pain sensitivity in two phases of the formalin test. This pain attenuation due to the co‐administration of spexin and progesterone was more potent than spexin‐induced analgesia. According to the present results, spexin has a modulatory effect on pain sensitivity, which becomes more pronounced by progesterone administration.