Binding characteristics of delta opioid receptors in different regions of the brain of young and old male rats as studied with the highly selective ligand [D-PEN2-D-PEN5] enkephalin

1992 ◽  
Vol 4 (1) ◽  
pp. 69-75 ◽  
Author(s):  
D. Dondi ◽  
Roberto Maggi ◽  
P. Limonta ◽  
L. Martini ◽  
F. Piva
Keyword(s):  
Opioid Receptors ◽  
Male Rats ◽  
Binding Characteristics ◽  
Delta Opioid Receptors ◽  
Selective Ligand ◽  
The Brain

Subanalgesic morphine doses augment fentanyl analgesia by interacting with delta opioid receptors in male rats

2021 ◽  
Author(s):  
Katherine E. Barker ◽  
Alynn J. Lecznar ◽  
Jill M. Schumacher ◽  
Jeffrey S. Morris ◽  
Howard B. Gutstein
Keyword(s):  
Opioid Receptors ◽  
Male Rats ◽  
Delta Opioid Receptors

Distribution of kappa opioid receptors in the brain of young and old male rats

Life Sciences ◽  
1989 ◽  
Vol 45 (22) ◽  
pp. 2085-2092 ◽  
Author(s):  
Roberto Maggi ◽  
Patrizia Limonta ◽  
Donatella Dondi ◽  
Luciano Martini ◽  
Flavio Piva
Keyword(s):  
Opioid Receptors ◽  
Male Rats ◽  
Kappa Opioid Receptors ◽  
Kappa Opioid ◽  
The Brain

Chronic immobilization stress induces anxiety-related behaviors and affects brain essential minerals in male rats

2020 ◽  
pp. 1-8
Author(s):  
Zafer Sahin ◽  
Alpaslan Ozkurkculer ◽  
Omer Faruk Kalkan ◽  
Ahmet Ozkaya ◽  
Aynur Koc ◽  
...  
Keyword(s):  
Immobilization Stress ◽  
Central Area ◽  
Essential Elements ◽  
Male Rats ◽  
Control Group ◽  
Male Wistar Rats ◽  
Swimming Test ◽  
The Brain ◽  
Center Area ◽  
Chronic Immobilization Stress

Abstract. Alterations of essential elements in the brain are associated with the pathophysiology of many neuropsychiatric disorders. It is known that chronic/overwhelming stress may cause some anxiety and/or depression. We aimed to investigate the effects of two different chronic immobilization stress protocols on anxiety-related behaviors and brain minerals. Adult male Wistar rats were divided into 3 groups as follows ( n = 10/group): control, immobilization stress-1 (45 minutes daily for 7-day) and immobilization stress-2 (45 minutes twice a day for 7-day). Stress-related behaviors were evaluated by open field test and forced swimming test. In the immobilization stress-1 and immobilization stress-2 groups, percentage of time spent in the central area (6.38 ± 0.41% and 6.28 ± 1.03% respectively, p < 0.05) and rearing frequency (2.75 ± 0.41 and 3.85 ± 0.46, p < 0.01 and p < 0.05, respectively) were lower, latency to center area (49.11 ± 5.87 s and 44.92 ± 8.04 s, p < 0.01 and p < 0.01, respectively), were higher than the control group (8.65 ± 0.49%, 5.37 ± 0.44 and 15.3 ± 3.32 s, respectively). In the immobilization stress-1 group, zinc (12.65 ± 0.1 ppm, p < 0.001), magnesium (170.4 ± 1.7 ppm, p < 0.005) and phosphate (2.76 ± 0.1 ppm, p < 0.05) levels were lower than the control group (13.87 ± 0.16 ppm, 179.31 ± 1.87 ppm and 3.11 ± 0.06 ppm, respectively). In the immobilization stress-2 group, magnesium (171.56 ± 1.87 ppm, p < 0.05), phosphate (2.44 ± 0.07 ppm, p < 0.001) levels were lower, and manganese (373.68 ± 5.76 ppb, p < 0.001) and copper (2.79 ± 0.15 ppm, p < 0.05) levels were higher than the control group (179.31 ± 1.87 ppm, 3.11 ± 0.06 ppm, 327.25 ± 8.35 ppb and 2.45 ± 0.05 ppm, respectively). Our results indicated that 7-day chronic immobilization stress increased anxiety-related behaviors in both stress groups. Zinc, magnesium, phosphate, copper and manganese levels were affected in the brain.

Effect of opioid peptides on liver function after patial hepatectomy

2018 ◽  
pp. 67-71
Author(s):  
А.В. Солин ◽  
А.Ю. Ляшев ◽  
Ю.Д. Ляшев
Keyword(s):  
Lactate Dehydrogenase ◽  
Liver Failure ◽  
Partial Hepatectomy ◽  
Opioid Receptors ◽  
Total Protein ◽  
Pronounced Effect ◽  
Male Rats ◽  
Control Group ◽  
Peptide Molecule ◽  
Selective Agonists

Цель исследования - сравнительный анализ влияния селективных агонистов отдельных классов опиоидных рецепторов на белковосинтетическую функцию печени, развитие цитолитического и холестатического синдромов у крыс, подвергшихся частичной гепатэктомии. Методика. Работа выполнена на 152 крысах-самцах Вистар массой 200-250 г. Частичную гепатэктомию выполняли по методу, описанному Higgins G.M. и Anderson R.M. с удалением 70% ткани печени. В плазме крови определяли концентрации общего белка, альбуминов, общего билирубина, активность аланинтрансаминазы (АЛТ), аспартаттрансаминазы (АСТ), лактатдегидрогеназы (ЛДГ) традиционными методами. Опиоиды: DAGO в дозе 6,3 мкг/кг, DSLET в дозе 10,0 мкг/кг, динорфин А (1-13) в дозе 20,1 мкг/кг, вводили внутрибрюшинно ежедневно 1 раз в сутки в течение 5 сут. эксперимента в объеме 0,2 мл. Контрольным животным аналогично вводили физраствор. Результаты. Удаление 70% ткани печени у крыс-самцов Вистар сопровождается развитием печеночной недостаточности, проявляющейся гипербилирубинемией, гипоальбуминемией, гипопротеинемией, повышением активности трансаминаз и лактатдегидрогеназы. Применение селективных агонистов опиоидных рецепторов у крыс, которым моделировали частичную гепатэктомию, оказывало гепатопротективное действие и снижало выраженность проявлений печеночной недостаточности, начиная с 3-х сут. после резекции. Активность трансаминаз, лактатдегидрогеназы и концентрация общего билирубина у животных, которым вводили опиоиды, были существенно ниже, чем в контрольной группе. Содержание общего белка и альбуминов было статистически значимо выше в группах, которые получали исследованные пептиды, по сравнению с контрольной группой на 7-е сут. после частичной гепатэктомии. Наиболее выраженное действие проявлял селективный агонист опиоидных мю-рецепторов DAGO. По нашему мнению, такое влияние пептидов объясняется присущими им антиоксидантным и антигипоксическим эффектами, что снижает повреждающее действие оперативного вмешательства на печень. Более выраженное влияние DAGO связано, по-видимому, с особенностями распределения опиоидных рецепторов или устойчивостью пептида к действию эндопептидаз благодаря модификациям в молекуле пептида. Заключение. Применение опиоидов стимулирует восстановление функциональной активности печени после частичной гепатэктомии. Наибольший эффект отмечается при введении мю-агониста DAGO. Aim. The aim of the study was to compare effects of selective agonists of opioid receptors from different classes on the protein-synthesizing function of liver and development of cytolytic and cholestatic syndromes in rats after partial hepatectomy. Methods. The study was conducted on 152 Wistar male rats weighing 200-250 g. The animals were subjected to partial hepatectomy according to the Higgins and Anderson method. Concentrations of total protein, albumin, total bilirubin, and activities of alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase were measured in plasma using standard methods. The opioids, DAGO (6.3 mg/kg), DSLET (10.0 mg/kg), and dynorphin A (1-13) (20.1 mg/kg), were injected in 0.2 ml of saline daily for 5 days. Control animals were injected with 0.2 ml of saline for 5 days. Results. Resection of 70% of liver tissue resulted in development of liver failure as evidenced by hyperbilirubinemia, hypoalbuminemia, hypoproteinemia, and increased transaminase and lactate dehydrogenase activities. Selective agonists of opioid receptors administered to the rats after partial hepatectomy exerted a hepatoprotective effect and alleviated the signs of liver failure beginning from the 3 day after resection. Transaminase and lactate dehydrogenase activities were significantly lower in opioid-treated rats than in the control group. Levels of total protein and albumins were significantly higher in the groups injected with the study peptides compared to the control group on the 7 day after partial hepatectomy. The selective agonist of opioid m-receptors, DAGO, exerted the most pronounced effect. Apparently, the similar effects of peptides were due to their antioxidant and anti-hypoxic action, which alleviated the detrimental effect of liver surgery. The more pronounced effect of DAGO apparently resulted from peculiarities of opioid receptors distribution or peptide resistance to endopeptidase action due to modifications of the peptide molecule. Conclusion. Administration of opioids stimulated restoration of liver functional activity after partial hepatectomy. Injections of the m-agonist, DAGO, produced the most pronounced effect.

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