ABSTRACT
Background: Ghrelin is a peptide with attenuating effect on inflammatory pain. Both anti- and pro-inflammatory mediators have a role in the nociception and development of pain and hyperalgesia. IL-10 and TGF-beta are anti-inflammatory cytokines and inhibit the expression of pro-inflammatory cytokines related to peripheral and central inflammatory pain. In this study, the effects of i.p. injection of ghrelin on the early and the late phases of pain, as well as serum levels of IL-10 and TGF-beta, as anti-inflammatory cytokines, were investigated in formalin-induced pain in male rats
Methods: Adult male Wistar rats [n=48] were randomly divided into six groups: control, formalin+saline, ghrelin [40, 80, and 160 microg/kg], and morphine. Ghrelin was administered i.p. 30 min before inducing pain by formalin. Pain induced by intraplantar [i.pl.] injection of 50 microl formalin 5%, and pain behavior was studied for 60 min. Serum IL-10 and TGF-beta levels were assessed by ELISA method
Results: The findings of the present study showed that ghrelin with high doses [80 and 160 microg/kg] significantly reduced pain intensity in both the early and the late phases of pain. The serum levels of cytokines, IL-10, and TGF-beta1 showed a significant elevation with ghrelin at dose of 160 microg/kg
Conclusion: Ghrelin is effective in reducing the intensity of both the early and the late phases of inflammatory pain. It seems that ghrelin exerts its analgesic effects in part by increasing the serum levels of anti-inflammatory cytokines
ABSTRACT
Several studies have reported improved response of exercised hearts to myocardial infarction [MI] This study was aimed to evaluate the preventive role of treadmill exercise and diosgenin on cardiac marker enzymes, thiobarbituric acid reactive substances [TEARS], total antioxidant status [TAS], lipids, and electrocardiographic [ECG] patterns in isoproterenol [ISO]-induced myocardial infarction [MI] in male Wistar rats. One hundred Wistar rats were divided into ten groups: Control rats [C], saline [S], L-cremephor [LC] exercise [E], diosgenin dissolved in L-cremephor [15 nig/kg/day] [D], exereise+ diosgenin [E+D], ISO injected [150 mg/kg] [ISO], exercise + ISO [E+ISO], diosgenin + ISO [D+ISO] and exercise diosgenin + ISO [E+D+ISO] At the end of the experiment all animals anesthetized and blood samples were collected for biochemical estimation and also the ECG patterns were recorded. Exercise and diosgenin pretreatment significantly decreased the lactate dehydrogenase [LDH] and TEARS level in ISO injected animals. Exercise and diosgenin pretreatment significantly decreased serum total cholesterol and increased high density lipoprotein [HDL-C]. ISO-treated rats showed pathological Q waves along with elevated ST segments. The altered electrocardiograms [ECG] of ISO-treated rats were also restored to near normal by diosgenin and exercise, but exercise and diosgenin had synergistic effects. The present investigation demonstrates that combination of diosgenin and exercise exhibited significant protection against ISO induced electrocardiographical and biochemical changes. The cadioprotective mechanism [s] appear to be through changing lipid metabolism