Opioid peptides and testicular activity in the lizard Podarcis s. sicula Raf

1994 ◽  
Vol 143 (3) ◽  
pp. 565-571 ◽  
Author(s):  
G Ciarcia ◽  
F Facchinetti ◽  
M Vallarino ◽  
M Pestarino ◽  
M Paolucci ◽  
...  
Keyword(s):  
Opioid Peptides ◽  
High Performance ◽  
Physiological Role ◽  
Reproductive Activity ◽  
Opioid System ◽  
Endogenous Opioid System ◽  
Endogenous Opioid ◽  
Naltrexone Treatment

Abstract In mammals endorphinergic systems have been shown to modulate reproductive processes and β-endorphin (β-EP) has been found to influence sexual functions, acting at the hypothalamus-pituitary-gonadal axis level. Using immunocytochemical and in vitro studies, evidence for a diffuse pro-opiomelanocortin-related opioid system in the lizard Podarcis s. sicula was produced. In the testis, β-EP immunoreactivity showed seasonal variation, being most pronounced in the interstitial cells of sexually quiescent lizards (December). Reverse-phase high-performance liquid chromatography, coupled with radioimmunoassay and immunocytochemistry, showed that β-EP and acetyl β-EP increased during December, while their concentrations were low during April, when the highest testicular activity occurred. Using in vivo studies, it was found that naltrexone treatment, blocking pituitary opioid receptor, increased androgen levels in the plasma and in the testis. It was also found with in vitro studies that the endogenous opioid system inhibits gonadotrophin release and therefore androgen production by the testis. The data reported here provide evidence for the physiological role played by opioid peptides at the pituitary level to regulate the seasonal reproductive activity of the lizard Podarcis s. sicula. Journal of Endocrinology (1994) 143, 565–571

Effects of porcine relaxin on oxytocin release from the neurohypophysis in the anaesthetized lactating rat

1986 ◽  
Vol 109 (3) ◽  
pp. 393-397 ◽  
Author(s):  
K. T. O'Byrne ◽  
L. Eltringham ◽  
G. Clarke ◽  
A. J. S. Summerlee
Keyword(s):  
Opioid Peptides ◽  
Inhibitory Effect ◽  
Opioid Antagonist ◽  
Dependent Manner ◽  
Endogenous Opioid Peptides ◽  
Endogenous Opioid ◽  
Oxytocin Release ◽  
Relaxin 2

ABSTRACT The effect of relaxin on electrically evoked release of oxytocin from the posterior pituitary was examined by monitoring changes in intramammary pressure in the anaesthetized lactating rat. The amount of oxytocin released by electrical stimulation of the neurohypophysis in vivo was dramatically reduced following i.v. injection of highly purified porcine relaxin (2·5–10 μg/rat). Relaxin inhibited oxytocin release in a dose-dependent manner and the onset of inhibition occurred within 6–10 min and lasted for 10–60 min. No effect on the sensitivity of the mammary gland to exogenous oxytocin was observed after relaxin treatment. During the period of inhibition, i.v. injection of the opioid antagonist naloxone chloride (1 mg/kg) completely and immediately restored electrically evoked oxytocin release. The neurohypophysis is known to contain endogenous opioid peptides, therefore the effect of relaxin on electrically stimulated release of oxytocin from the rat isolated neural lobe in vitro was examined. Relaxin (500–2000 ng/ml) failed to inhibit oxytocin release in vitro. The results suggest that relaxin can inhibit the release of oxytocin from terminals in the neurohypophysis, but by an indirect mechanism. This action appears to be mediated through endogenous opioid peptides whose source is not clear. They are unlikely to be of neurohypophysial origin and may probably come from the adrenal medulla, since acute adrenalectomy negated the inhibitory effect of relaxin on oxytocin release. J. Endocr. (1986) 109, 393–397

scholarly journals Formation of fetal opioid system

2016 ◽  
Vol 65 (2) ◽  
pp. 64-69 ◽  
Author(s):  
Anastasia A Yakovleva
Keyword(s):  
Growth Hormone ◽  
Opioid Peptides ◽  
Opioid System ◽  
Endogenous Opioid Peptides ◽  
Endogenous Opioid System ◽  
Endogenous Opioid ◽  
Placental Lactogens ◽  
Functional Development ◽  
The Central Nervous System ◽  
Different Tissues

The article presented literature review about of endogenous opioid system (EOS) formation consist of opioid receptors complex and its ligands (endogenous opioid peptides) in different tissues including placenta. It was shown that formation of fetal EOS is going with anatomic and functional development of the central nervous system and EOS expression begins in the placental tissues as soon as implantation and starts till the end of the pregnancy. Influence of opioid peptides on secretion progesterone, prolactin family peptides, growth hormone, placental lactogens and prolypherine from the trophoblast tissue is discussed.

Involvement of endogenous opioid peptides in the neuroendocrine response of ewe lambs to the introduction of a ram

1987 ◽  
Vol 115 (2) ◽  
pp. 333-339 ◽  
Author(s):  
S. C. Stansfield ◽  
P. G. Knight ◽  
N. Z. Al-Mauly ◽  
M. J. Bryant
Keyword(s):  
Median Eminence ◽  
Reproductive Activity ◽  
Pulse Frequency ◽  
Opioid Peptide ◽  
Endogenous Opioid ◽  
Endogenous Opioid Peptide ◽  
Ewe Lambs ◽  
Basal Release

ABSTRACT Prepubertal ewes can, under certain circumstances, be stimulated to ovulate by the novel introduction of a ram. The endocrine response to the presence of the ram is characterized by a rapid increase in the frequency of episodic release of LH. The purpose of this study was to investigate the effect of the presence of a ram on LH pulse frequency in vivo, gonadotrophin-releasing hormone (GnRH) and β-endorphin concentrations in the median eminence, and on the influence of the endogenous opioid peptide agonist [d-Ala2,N-Phe4,Met(0)ol5]-enkephalin (FK 33–824) on basal and depolarization-induced release of GnRH from median eminence tissue superfused in vitro. The study was performed at two prepubertal ages in August and September. In September, the introduction of a ram resulted in an increase in pulsatile release of LH, which was associated with an increase in the rate of basal release of GnRH from median eminence tissue superfused in vitro, and the development of a marked ability of FK 33–824 to suppress depolarization-induced release of GnRH. The concentration of β-endorphin in the median eminence was reduced in animals exposed to the ram at this time. In contrast, the introduction of a ram in August failed to stimulate an increase in LH pulse frequency, basal release of GnRH in vitro was not altered and FK 33–824 was ineffective in reducing depolarization-induced release of GnRH. These results suggest that the premature onset of reproductive activity induced by exposure to the ram may involve the participation of the endogenous opioid peptide system. J. Endocr. (1987) 115, 333–339

scholarly journals Reward Processing by the Opioid System in the Brain

2009 ◽  
Vol 89 (4) ◽  
pp. 1379-1412 ◽  
Author(s):  
Julie Le Merrer ◽  
Jérôme A. J. Becker ◽  
Katia Befort ◽  
Brigitte L. Kieffer
Keyword(s):  
Opioid Peptides ◽  
Drugs Of Abuse ◽  
Gene Knockout ◽  
Reward Processing ◽  
Endogenous Opioids ◽  
Therapeutic Interventions ◽  
Opioid System ◽  
Endogenous Opioid System ◽  
Endogenous Opioid ◽  
Addictive Disorders

The opioid system consists of three receptors, mu, delta, and kappa, which are activated by endogenous opioid peptides processed from three protein precursors, proopiomelanocortin, proenkephalin, and prodynorphin. Opioid receptors are recruited in response to natural rewarding stimuli and drugs of abuse, and both endogenous opioids and their receptors are modified as addiction develops. Mechanisms whereby aberrant activation and modifications of the opioid system contribute to drug craving and relapse remain to be clarified. This review summarizes our present knowledge on brain sites where the endogenous opioid system controls hedonic responses and is modified in response to drugs of abuse in the rodent brain. We review 1) the latest data on the anatomy of the opioid system, 2) the consequences of local intracerebral pharmacological manipulation of the opioid system on reinforced behaviors, 3) the consequences of gene knockout on reinforced behaviors and drug dependence, and 4) the consequences of chronic exposure to drugs of abuse on expression levels of opioid system genes. Future studies will establish key molecular actors of the system and neural sites where opioid peptides and receptors contribute to the onset of addictive disorders. Combined with data from human and nonhuman primate (not reviewed here), research in this extremely active field has implications both for our understanding of the biology of addiction and for therapeutic interventions to treat the disorder.

MODULATION BY CCK-B RECEPTORS OF THE ANTINOCICEPTIVE AND REWARDING PROPERTIES INDUCED BY THE ENDOGENOUS OPIOID SYSTEM

Analgesia ◽  
1995 ◽  
Vol 1 (4) ◽  
pp. 809-812
Author(s):  
O. Valverde ◽  
M.-C. Fournié-Zaluski ◽  
B. P. Roques ◽  
R. Maldonado
Keyword(s):  
Opioid System ◽  
Endogenous Opioid System ◽  
Endogenous Opioid

Phytochemical, Analytical and Medicinal Studies of Holoptelea integrifolia Roxb. Planch - A Review

2019 ◽  
Vol 5 (4) ◽  
pp. 270-277 ◽  
Author(s):  
Vijay Kumar ◽  
Simranjeet Singh ◽  
Ragini Bhadouria ◽  
Ravindra Singh ◽  
Om Prakash
Keyword(s):  
Liquid Chromatography ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
High Performance ◽  
Biologically Active ◽  
Toxicological Studies ◽  
Wide Range ◽  
Layer Chromatography

Holoptelea integrifolia Roxb. Planch (HI) has been used to treat various ailments including obesity, osteoarthritis, arthritis, inflammation, anemia, diabetes etc. To review the major phytochemicals and medicinal properties of HI, exhaustive bibliographic research was designed by means of various scientific search engines and databases. Only 12 phytochemicals have been reported including biologically active compounds like betulin, betulinic acid, epifriedlin, octacosanol, Friedlin, Holoptelin-A and Holoptelin-B. Analytical methods including the Thin Layer Chromatography (TLC), High-Performance Thin Layer Chromatography (HPTLC), High-Performance Liquid Chromatography (HPLC) and Liquid Chromatography With Mass Spectral (LC-MS) analysis have been used to analyze the HI. From medicinal potency point of view, these phytochemicals have a wide range of pharmacological activities such as antioxidant, antibacterial, anti-inflammatory, and anti-tumor. In the current review, it has been noticed that the mechanism of action of HI with biomolecules has not been fully explored. Pharmacology and toxicological studies are very few. This seems a huge literature gap to be fulfilled through the detailed in-vivo and in-vitro studies.

scholarly journals A novel PET tracer 18F-deoxy-thiamine: synthesis, metabolic kinetics, and evaluation on cerebral thiamine metabolism status

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Changpeng Wang ◽  
Siwei Zhang ◽  
Yuefei Zou ◽  
Hongzhao Ma ◽  
Donglang Jiang ◽  
...  
Keyword(s):  
High Performance ◽  
Specific Activity ◽  
High Accumulation ◽  
Metabolic Kinetics ◽  
Thiamine Metabolism ◽  
Pet Tracer ◽  
The Status ◽  
The Brain

Abstract Background Some neuropsychological diseases are associated with abnormal thiamine metabolism, including Korsakoff–Wernicke syndrome and Alzheimer’s disease. However, in vivo detection of the status of brain thiamine metabolism is still unavailable and needs to be developed. Methods A novel PET tracer of 18F-deoxy-thiamine was synthesized using an automated module via a two-step route. The main quality control parameters, such as specific activity and radiochemical purity, were evaluated by high-performance liquid chromatography (HPLC). Radiochemical concentration was determined by radioactivity calibrator. Metabolic kinetics and the level of 18F-deoxy-thiamine in brains of mice and marmosets were studied by micro-positron emission tomography/computed tomography (PET/CT). In vivo stability, renal excretion rate, and biodistribution of 18F-deoxy-thiamine in the mice were assayed using HPLC and γ-counter, respectively. Also, the correlation between the retention of cerebral 18F-deoxy-thiamine in 60 min after injection as represented by the area under the curve (AUC) and blood thiamine levels was investigated. Results The 18F-deoxy-thiamine was stable both in vitro and in vivo. The uptake and clearance of 18F-deoxy-thiamine were quick in the mice. It reached the max standard uptake value (SUVmax) of 4.61 ± 0.53 in the liver within 1 min, 18.67 ± 7.04 in the kidney within half a minute. The SUV dropped to 0.72 ± 0.05 and 0.77 ± 0.35 after 60 min of injection in the liver and kidney, respectively. After injection, kidney, liver, and pancreas exhibited high accumulation level of 18F-deoxy-thiamine, while brain, muscle, fat, and gonad showed low accumulation concentration, consistent with previous reports on thiamine distribution in mice. Within 90 min after injection, the level of 18F-deoxy-thiamine in the brain of C57BL/6 mice with thiamine deficiency (TD) was 1.9 times higher than that in control mice, and was 3.1 times higher in ICR mice with TD than that in control mice. The AUC of the tracer in the brain of marmosets within 60 min was 29.33 ± 5.15 and negatively correlated with blood thiamine diphosphate levels (r = − 0.985, p = 0.015). Conclusion The 18F-deoxy-thiamine meets the requirements for ideal PET tracer for in vivo detecting the status of cerebral thiamine metabolism.

scholarly journals In Vitro Antibacterial Effect of the Methanolic Extract of the Korean Soybean Fermented Product Doenjang against Staphylococcus aureus

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2319
Author(s):  
Klara Lalouckova ◽  
Lucie Mala ◽  
Petr Marsik ◽  
Eva Skrivanova
Keyword(s):  
Staphylococcus Aureus ◽  
High Performance ◽  
Methanolic Extract ◽  
Bioactive Substances ◽  
Microdilution Method ◽  
Antibacterial Compound ◽  
Fermented Product ◽  
Broth Microdilution Method

Ultra-high performance liquid chromatography/mass spectrometry showed soyasaponin I and the isoflavones daidzein, genistein, and glycitein to be the main components of the methanolic extract of the Korean soybean fermented product doenjang, which is known to be a rich source of naturally occurring bioactive substances, at average contents of 515.40, 236.30, 131.23, and 29.00 ng/mg, respectively. The antimicrobial activity of the methanolic extract of doenjang against nine Staphylococcusaureus strains was determined in vitro by the broth microdilution method to investigate its potential to serve as an alternative antibacterial compound. The results suggest that the extract is an effective antistaphylococcal agent at concentrations of 2048–4096 µg/mL. Moreover, the tested extract also showed the ability to inhibit the growth of both methicillin-sensitive and methicillin-resistant animal and clinical S. aureus isolates. The growth kinetics of the chosen strains of S. aureus at the minimum inhibitory concentration of the methanolic extract of doenjang support the idea that the tested extract acts as an antibacterial compound. To the best of our knowledge, this is the first report on the antistaphylococcal action of the methanolic extract of doenjang thus, additional studies including in vivo testing are necessary to confirm this hypothesis.

scholarly journals High-Throughput Identification of Organic Compounds from Polygoni Multiflori Radix Praeparata (Zhiheshouwu) by UHPLC-Q-Exactive Orbitrap-MS

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3977
Author(s):  
Shaoyun Wang ◽  
Xiaozhu Sun ◽  
Shuo An ◽  
Fang Sang ◽  
Yunli Zhao ◽  
...  
Keyword(s):  
High Performance ◽  
Chemical Constituents ◽  
Water Extract ◽  
Ethanol Extract ◽  
In Vivo Studies ◽  
Polygonum Multiflorum ◽  
Q Exactive ◽  
Orbitrap Ms

Polygoni Multiflori Radix Praeparata (PMRP), as the processed product of tuberous roots of Polygonum multiflorum Thunb., is one of the most famous traditional Chinese medicines, with a long history. However, in recent years, liver adverse reactions linked to PMRP have been frequently reported. Our work attempted to investigate the chemical constituents of PMRP for clinical research and safe medication. In this study, an effective and rapid method was established to separate and characterize the constituents in PMRP by combining ultra-high performance liquid chromatography with hybrid quadrupole-orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS). Based on the accurate mass measurements for molecular and characteristic fragment ions, a total of 103 compounds, including 24 anthraquinones, 21 stilbenes, 15 phenolic acids, 14 flavones, and 29 other compounds were identified or tentatively characterized. Forty-eight compounds were tentatively characterized from PMRP for the first time, and their fragmentation behaviors were summarized. There were 101 components in PMRP ethanol extract (PMRPE) and 91 components in PMRP water extract (PMRPW). Simultaneously, the peak areas of several potential xenobiotic components were compared in the detection, which showed that PMRPE has a higher content of anthraquinones and stilbenes. The obtained results can be used in pharmacological and toxicological research and provided useful information for further in vitro and in vivo studies.

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