Abstract：
:A role of D2-dopaminergic neurotransmission in the regulation of melatonin biosynthesis in retina was studied in vivo in chickens. The nighttime rise in serotonin N-acetyltransferase (NAT)--the penultimate and key regulatory melatonin-synthesizing enzyme--was potently inhibited by both acute light exposure and agonists of dopamine D2-receptor (quinpirole, bromocriptine, and apomorphine). Spiroperidol, a selective dopamine D2-receptor blocker, increased the enzyme activity in light-exposed chickens, but had no effect in animals kept in darkness. Inhibitors of cyclic nucleotide phosphodiesterase, aminophylline, and 3-isobutyl-1-methylxanthine given peripherally, along with a direct adenylate cyclase activator forskolin injected directly into the eye, mimicked the action of darkness, and markedly enhanced the retinal NAT activity when administered to animals maintained in an illuminated environment. Dopamine D2-receptor agonists had no effect on aminophylline-stimulated enzyme activity, whereas spiroperidol enhanced it. Forskolin-driven NAT activity was suppressed by quinpirole. Spiroperidol and aminophylline given alone at different times of day under light conditions stimulated NAT activity, and their effects were mainly additive when given in combination. SCH 23390, a selective D1-dopamine receptor antagonist, did not affect the rise in NAT activity of chicken retina produced by either darkness or by aminophylline. The results provide further evidence that dopamine, acting via D2-receptors, mediates the inhibitory effects of light on the cyclic AMP-dependent dark-evoked induction of NAT activity in chicken retina.
journal_name
J Pineal Resjournal_title
Journal of pineal researchauthors
Zawilska JB,Kazula A,Zurawska E,Nowak JZdoi
10.1111/j.1600-079x.1991.tb00466.xsubject
Has Abstractpub_date
1991-10-01 00:00:00pages
116-22issue
3-4eissn
0742-3098issn
1600-079Xjournal_volume
11pub_type
杂志文章abstract：:The frequency of mitoses of adrenaline (A) cells and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male, 53-day-old Holtzman rats (n = 133) was investigated by means of light microscopy. Animals were killed at eight time points during a standardized 2...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1990.tb00803.x
更新日期：1990-01-01 00:00:00
abstract：:Melatonin plays an important role in regulating circadian rhythms. It also acts as a potent antioxidant and regulates glucose and lipid metabolism, although the exact action mechanism is not clear. The α2-HS-glycoprotein gene (AHSG) and its protein, fetuin-A (FETUA), are one of the hepatokines and are known to be asso...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/jpi.12493
更新日期：2018-09-01 00:00:00
abstract：:Urotoxicity is one of the major problems associated with cyclophosphamide (CP) chemotherapy in cancer patients. Melatonin is a potent antioxidant and reduces CP-induced urotoxicity. However, the molecular mechanisms of protection offered by melatonin are not yet clear. The present study investigated the role of nuclea...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2010.00756.x
更新日期：2010-05-01 00:00:00
abstract：:Despite state-of-the-art pharmaceutical regimens, continuous improvements in diagnostic techniques as well as refinements in equipment and interventional procedures, many diseases remain refractory to conventional therapies. Recent advances in stem cell (SC) biology have opened an avenue to exploring its therapeutic p...
journal_title：Journal of pineal research
pub_type： 杂志文章,评审
doi：10.1111/jpi.12372
更新日期：2017-03-01 00:00:00
abstract：:Melatonin protects cells against various types of oxidative stress-induced apoptosis due primarily to its ability to effectively scavenge pathological and disease condition-augmented generation of mitochondrial reactive oxygen species (mROS). Once produced, mROS indiscriminately damage mitochondrial components and mor...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2009.00721.x
更新日期：2010-01-01 00:00:00
abstract：:We evaluated the feasibility of using morning urine samples in epidemiological studies aimed at clarifying the relationship between nocturnal melatonin levels and breast cancer risk. Initially, a laboratory-based study of 29 women (40- 70 yr old) was performed to examine the correlation between plasma melatonin levels...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1034/j.1600-079x.2000.280106.x
更新日期：2000-01-01 00:00:00
abstract：:Female Syrian hamsters were kept in a light (14:10 h light:dark cycle, lights on 0600 h)- and temperature (22 or 30 degrees C)-controlled room; some groups were treated with an afternoon s.c. injection of melatonin (6.25, 12.5, or 25 micrograms/day) for 11 or 14 weeks. The melatonin-induced suppression of the reproduc...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1988.tb00656.x
更新日期：1988-01-01 00:00:00
abstract：:Constitutive activation and gemcitabine induction of nuclear factor-κB (NF-κB) contribute to the aggressive behavior and chemotherapeutic resistance of pancreatic ductal adenocarcinoma (PDAC). Thus, targeting the NF-κB pathway has proven an insurmountable challenge for PDAC therapy. In this study, we investigated whet...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/jpi.12285
更新日期：2016-01-01 00:00:00
abstract：:A link between endotoxemia and nonalcoholic fatty liver disease (NAFLD) has been demonstrated in human and rodent animals. Nevertheless, the molecular mechanisms of endotoxin-evoked NAFLD remain poorly understood. We hypothesize that reactive oxygen species (ROS) mediate lipopolysaccharide (LPS)-evoked hepatic lipid a...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2011.00905.x
更新日期：2011-11-01 00:00:00
abstract：:Melatonin, an endogenous neurohormone secreted by the pineal gland, has a variety of physiological functions and neuroprotective effects. However, its protective role on the neural tube defects (NTDs) was not very clear. The aim of this study was to investigate the effects of melatonin on the incidence of NTDs (includ...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/jpi.12282
更新日期：2015-11-01 00:00:00
abstract：:In three separate experiments, the effect of acute exposure to either artificial or natural light during darkness of pineal N-acetyltransferase (NAT) activity and melatonin content was studied in the cotton rat (Sigmodon hispidus). The exposure of animals to an artificial-light irradiance of 160,000 microW/cm2 during ...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1985.tb00717.x
更新日期：1985-01-01 00:00:00
abstract：:In chronically inflamed animals, adrenal hormones exert a positive control on the secretion of melatonin by the pineal gland. In this paper, the mechanism of corticosterone as a modulator of melatonin and N-acetylserotonin (NAS) was determined. Rat pineal glands in culture, stimulated for 5 hr with noradrenaline (10 n...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2004.00191.x
更新日期：2005-04-01 00:00:00
abstract：:Melatonin is a powerful antioxidant and free radical scavenger. A large body of in vivo and in vitro evidence shows that melatonin effectively inhibits membrane lipid peroxidation; this damage was based on the measurement of malondialdehyde and/or 4-hydroxynonenal levels. In the current study, for the first time using...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2005.00311.x
更新日期：2006-05-01 00:00:00
abstract：:Chronic hyperhomocysteinemia is a risk factor in cardiovascular diseases and neurodegeneration. Among the putative mechanisms of homocysteine-induced neurotoxicity, an increased production of reactive oxygen species has been suggested. However, elevated homocysteine levels might disturb neurogenesis during brain devel...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2007.00506.x
更新日期：2008-03-01 00:00:00
abstract：:Melatonin and its precursor, l-tryptophan, have been shown to exert gastroprotective effects in animals, but their influence on the gastric damage by aspirin (ASA) in humans has been sparingly investigated. In this study, we designed to determine the effects of melatonin and l-tryptophan on ASA-induced gastric mucosal...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.2010.00755.x
更新日期：2010-05-01 00:00:00
abstract：:We tested whether combined melatonin (Mel) and exendin-4 (Ex4) treatment can better preserve glomerular structural integrity after ischemia-reperfusion (IR) injury compared with either alone. Adult male Sprague Dawley rats (n = 50) were equally divided into sham control (SC), IR, IR-Ex4 (10 μg/kg subcutaneously 30 min...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/jpi.12273
更新日期：2015-11-01 00:00:00
abstract：:Our objective was to suppress the daily surge of melatonin in serum of prepubertal dairy heifers by manipulating intensity of light (Experiment 1) and duration of exposure to light (Experiment 2). Heifers in Experiment 1 were exposed to either 12 hr of darkness (000 lux, control), or 400, 800, or 1,200 lux of light du...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1992.tb00046.x
更新日期：1992-05-01 00:00:00
abstract：:Excessive activity of NADPH oxidase (Nox) is considered to be of importance for the progress of diabetic nephropathy. The aim of the study was to elucidate the effect of melatonin, known for its nephroprotective properties, on Nox activity under diabetic conditions. The experiments were performed on three groups of an...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/jpi.12296
更新日期：2016-01-01 00:00:00
abstract：:Melatonin is a very potent and efficient endogenous radical scavenger. The pineal indolamine reacts with the highly toxic hydroxyl radical and provides on-site protection against oxidative damage to biomolecules within every cellular compartment. Melatonin acts as a primary non-enzymatic antioxidative defense against ...
journal_title：Journal of pineal research
pub_type： 杂志文章,评审
doi：10.1111/j.1600-079x.1993.tb00498.x
更新日期：1993-05-01 00:00:00
abstract：:Fetal intrauterine growth restriction (IUGR) is a serious pregnancy complication associated with increased rates of perinatal morbidity and mortality, and ultimately with long-term neurodevelopmental impairments. No intervention currently exists that can improve the structure and function of the IUGR brain before birt...
journal_title：Journal of pineal research
pub_type： 临床试验,杂志文章
doi：10.1111/jpi.12121
更新日期：2014-04-01 00:00:00
abstract：:Studies on farm animals have contributed significantly to our increased understanding of basic melatonin-related physiological mechanisms, as well as to the regulation of reproduction and pelage in individual domestic species. This review concentrates on recent work on the role of melatonin in the regulation of porcin...
journal_title：Journal of pineal research
pub_type： 杂志文章,评审
doi：10.1111/j.1600-079x.1994.tb00097.x
更新日期：1994-05-01 00:00:00
abstract：:The effects of melatonin (3 mg/kg i.p.) and the melatonin receptor agonist S-20098 (3 mg/kg i.p.) on the vigilance states, electroencephalogram power spectra (0.25-25.0 Hz), and cortical temperature were determined in eight rats in the first 6-hr interval of the 12-hr light period. Compared to the vehicle injection bo...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1994.tb00078.x
更新日期：1994-01-01 00:00:00
abstract：:When organic compounds are irradiated with UV light at 254 nm, part of their covalent bonds can dissociate if the compound absorbs light at that wavelength. Therefore, photo-degradation depends strongly on the wavelength used. The energy of a light quanta at 254 nm amounts to approximately 110 kcal/mol quanta, which i...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.2007.00536.x
更新日期：2008-05-01 00:00:00
abstract：:The purpose of the present studies using artificial light was to determine how the timing and duration of exposure influence the light-induced suppression of pineal melatonin levels in hamsters. An 8-min exposure to 0.186 microW/cm2 of cool white fluorescent light caused a continued depression of pineal melatonin even...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1984.tb00202.x
更新日期：1984-01-01 00:00:00
abstract：:We tested the hypothesis that melatonin (Mel) enhances exogenous mitochondria (Mito) treatment against rodent hepatic ischemia-reperfusion (IR) injury. In vitro study utilized three groups of hepatocytes (i.e. nontreatment, menadione, and menadione-melatonin treatment, 4.0 × 10(5) each), while in vivo study used adult...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/jpi.12326
更新日期：2016-08-01 00:00:00
abstract：:Oxidative stress is reported as one of the most widely accepted mechanisms of maneb (MB)- and paraquat (PQ)-induced nigrostriatal dopaminergic neurodegeneration leading to the Parkinson's disease (PD) phenotype. The study investigated the effects of silymarin, an antioxidant of plant origin, and melatonin, an indoleam...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2010.00819.x
更新日期：2011-03-01 00:00:00
abstract：:In a recent study melatonin (N-acetyl-5-methoxytryptamine), a well-investigated animal molecule but minimally studied in plants, was seen to have a physiological role as growth-promoting molecule in lupin hypocotyls. In the present study, the role of melatonin as a growth promoter is extended to coleoptiles of canary ...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2005.00226.x
更新日期：2005-09-01 00:00:00
abstract：:Melatonin is an excellent free radical scavenger, reacting with tert-butoxyl and cumyloxyl radicals with rate constants of 3.4 x 10(7) and 6.7 x 10(7) M-1s-1, respectively. Reaction with benzophenone triplet occurs with a near-diffusion-controlled rate constant of 7.6 x 10(9) M-1s-1 in acetonitrile and probably involv...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1995.tb00188.x
更新日期：1995-11-01 00:00:00
abstract：:The aim of the study was to determine whether a discrepancy between the genetically determined endogenous circadian period and an abnormally long Zeitgeber period disturbs the development of melatonin synthesis. Breeding pairs of rats were kept under 12:12- or 14:14-hr light:dark (LD) conditions. Pineal melatonin cont...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079x.1996.tb00283.x
更新日期：1996-10-01 00:00:00
abstract：:The purpose of this study was to evaluate the effect of melatonin on oxidative stress occurring in the brain after routine lobectomy neurosurgery procedures. Different concentrations of melatonin (5, 15 and 150 mg/kg) were administered 1 hr before lobectomy in a rodent surgical brain injury (SBI) model. Neurological o...
journal_title：Journal of pineal research
pub_type： 杂志文章
doi：10.1111/j.1600-079X.2008.00607.x
更新日期：2009-01-01 00:00:00
