ABSTRACT
Opioid receptors change in CNS by anti thyroid hormones drugs. In this study effect of acute and chronic methimazole [aMTZ and cMTZ] administration on morphine withdrawal were investigated. In this experimental study adult male mice divided into control and experimental groups receiving aMTZ or cMTZ. All groups were addicted to morphine and morphine withdrawal was induced by naloxone and jumping, rearing and climbing signs were evaluated. Acute MTZ and chronic MTZ increased the climbing and jumping [p< 0.01, p< 0.001]. cMTZ was more potent than the acute one. MTZ probably influences an opioid abstinence directly and/or indirectly through decrement of thyroid hormones
ABSTRACT
With appearance of nano particles as an important component in modern medicine, and considering to new properties of these components, study of their effects on human health is essential. Since zinc components influences mechanisms of nociception, the aim of this study was to evaluate the effect of nano zinc oxide as a new source of zinc and important components in pharmaceutical and hygienic cosmetic production on nociception in adult female rats. Female rats were divided into groups: control [receiving saline 0.9%] and receiving nano ZnO [0.5, 1, and 5 mg/kg]. Hot plate and tail flick tests as models of somatic acute pain were used for evaluation of the pain. The mean of latency time in paw licking and tail withdrawal respectively recorded as nociception indexes in each test for every animal. The animal numbers in each group was seven. In tail flick test, nano ZnO [0.5, 1 mg/kg] and in the hot plate test in dose of 0.5 mg/kg, induces significant analgesia [p<0.05] and with increasing of dose reduced its analgesic effect. It seems nano ZnO inhibit the nociception mechanisms and these analgesic properties are more efficient in the low doses. Probably by increasing dose of nano particles aggregation phenomenon prevent of anti-nociception effects of nano ZnO
ABSTRACT
In recent years, nanotechnology has produced new forms of materials that are more effective than their predecessors. Magnesium is an essential element in the human body and certain studies have proved that its deficiency can induce anxiety in animals. In this study, the effect of magnesium oxide nanoparticles [MgO NPs] on anxiety, related behaviors, and interaction between their effects and anxiolytic effect of the exercises were examined in comparison to the conventional MgO [cMgO]. Adult male Wistar rats weighing 190 +/- 20 gr were divided into control groups [receiving saline, without physical activity], and exercise groups [receiving cMgO and/or MgO NPs [1 mg/kg i.p.] daily for 6 weeks with or/and without exercise]. Exercise groups were performing their daily physical activity protocol 30 minutes after injection. At the end of period, an elevated plus maze apparatus was used to evaluate the anxiety [%pen arm time [%OAT] and%open arm entries [%OAE] and locomotor activity. Exercise significantly increased%OAT and%OAE [P<0.05]. MgO NPs caused an increase in%OAT, while cMgO did not have any effect on%OAT or%OAE. There was no notable difference among anxiety parameters in exercise groups with or without taking MgO NPs. It seems that the anxiolytic effect of exercise and MgO NPs has been mediated through common mechanisms that were a part of the anxiety process of the central nervous system
Subject(s)
Animals, Laboratory , Anti-Anxiety Agents , Nanoparticles , Exercise , Rats, Wistar , Anxiety , Motor ActivityABSTRACT
Background: Anabolic-Androgenic Steroids [AAS] are mainly abused by athletes for improvement of muscle performance. Data suggest that the effect of AAS on neurobio-chemicals related to behavioral response, may be underlies psychological adverse effects
Physical activity has beneficial psychophysiological effects, which may be related to increased serum levels of endogenous opioid peptides during exercise. In the present study we aimed to study the effect of chronic administration of nandrolone decanoate on beta-endorphin and met-enkephalin level in exercising rats
Methods: In this experimental study, forty male Wistar rats were randomly assigned in two main groups of sedentary and trained [2 weeks swimming exercise]
Animals in each group were divided in two subgroups of control [received nandrolone solvent] and drug treatment [received nandrolone 15 mg/kg, 5 times/week]. After two weeks of swimming exercise and drug treatment, serum levels of beta-endorphin and met-enkephalin were measured using ELIZA
Results: Our data showed that two weeks of swimming exercise training significantly increased serum beta-endorphin [114+/-5 vs. 98+/-5 ng/1 in control group, P= 0.038] and met-enkephalin levels [1556+/-42 vs. 1475+/-27 ng/1 in control group, P= 0.25]
However, chronic administration of nandrolone decanoate in trained group considerably decreased beta-endorphin [84+/-4 vs. 114+/-5 ng/1 in control group, P= 0.002] and met-enkephalin levels [1378+/-36 vs. 1556+/-42 ng/1 in control group, P= 0.011]
The effect of supraphysiologic doses of nandrolone decanoate in control sedentary group was not statistically significant
Conclusion: In the present study we show that chronic nandrolone decanoate administration attenuates effects of two weeks swimming exercise on serum opioid peptide and reduces the level of beta-endorphin and met-enkephalin. Keeping in mind that opioidergic system play an important role in behavior, athletes abusing anabolic steroid drugs may potentially experience changes in mood and behavior
ABSTRACT
Chamomile is a beneficial herbal drug that is used as an anti-inflammatory, sedative and anti-allergic agent. The mechanism of action of matricaria recutita [MR], a specious of chamomile, in nociception in male and female animals is not fully understood. In this study, the sedative effect of a species of chamomile, MR, on acute pain was investigated in both male and female adult mice in the presence and absence of sex hormones. Male and female NMRI mice weighing 28 +/- 3 grams were used. Animals of each sex were divided into intact and gonadectomized groups. Intact group received saline or MR extract [10, 30, 50 mg/kg, intraperitoneally]. Gonadectomized group contained two subgroups: a] group that received saline or MR hydro alcoholic extract [50 mg/kg, I.P.], and b] group that received sex hormones [testosterone in male mice and estradiol benzoate and progesterone in female mice], both with and without MR extract [50mg/kg, IP]. The analgesia times in all groups were evaluated by hot plate test. MR increased analgesia time both in intact and gonadectomized male and female mice, but had no effect in the presence of pharmacological doses of testosterone [2 mg/kg, subcutaneous] in male mice, and estradiol benzoate [0.1 mg/kg, SC] and progesterone [0.5 mg/kg, SC] in female mice. It seems that MR can induce a pain-relieving effect with and without physiological doses of sex hormones in male and female mice, but sex hormones probably interact with its analgesic effect in their pharmacological doses