Abstract:
:A series of studies were conducted to determine the effects of leucine-(leu-) enkephalin and methionine-(met-) enkephalin on perfusion pressure. These experiments utilized isolated perfused femoral arterial preparations in pentobarbital-anesthetized cats. The enkephalins were administered intraarterially into the femoral artery and changes in perfusion pressure recorded. Leu-enkephalin in doses of 1 microgram to 320 micrograms produced significant dose-dependent decreases in perfusion pressure (4.0 +/- 1.3% with 1 microgram to 19.1 +/- 2.1% with 320 microgram). Similar declines in perfusion pressure (5.2 +/- 2.4% with 1 microgram to 21.7 +/- 4.1% with 320 micrograms) were observed following the administration of met-enkephalin. Pretreatment with naloxone (3 mg/kg) antagonized the effects of both enkephalins. Diphenhydramine (2 mg/kg) effectively antagonized the leu-enkephalin elicited decline in perfusion pressure but blocked the effects of met-enkephalin only at lower agonist doses. Propranolol treatment (4 mg/kg) did not alter the pressure responses to either enkephalin. The results of the study show that intraarterially administered enkephalins exert a vasodilatory effect on vasculature in skeletal muscle which may be direct, indirect or both. The differential antagonism of the effects of the two enkephalins suggest that the two opioids act through different receptors or multiple receptors.
journal_name
Life Scijournal_title
Life sciencesauthors
Moore RH 3rd,Dowling DAdoi
10.1016/0024-3205(82)90047-9subject
Has Abstractpub_date
1982-10-11 00:00:00pages
1559-66issue
15eissn
0024-3205issn
1879-0631pii
0024-3205(82)90047-9journal_volume
31pub_type
杂志文章相关文献
LIFE SCIENCES文献大全abstract::Unfertilized ova from Shad, a North Atlantic herring, contains a cytostatic inhibitor of T lymphocyte blastogenesis. The inhibitor has an estimated molecular weight of 10,000-30,000 Da, is heat stable, non dialyzable, and resistant to protease digestion and periodate oxidation. Although the inhibitor functions at an e...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(90)90336-p
更新日期:1990-01-01 00:00:00
abstract::Partially purified fractions from sheep pineal gland extracts, which show a fluorescence like pteridines, were shown to suppress the enzyme hydroxy-indole-o-methyltransferase (HIOMT) isolated from avian pineals and retinas. The results described demonstrate that the mechanism of inhibition of HIOMT activity is indepen...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(82)90022-4
更新日期:1982-04-19 00:00:00
abstract::Different ligands of both the "peripheral" and the "central" benzodiazepine receptors were tested for their ability to induce human monocyte chemotaxis. Only the ligands interacting with the "peripheral receptor" (diazepam and Ro 5-4864) were active, and their action was blocked by the specific antagonist PK 11-195, b...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(93)90275-8
更新日期:1993-01-01 00:00:00
abstract::Hypertension is closely associated with vascular endothelial dysfunction. The aim of this study was to investigate the effects of Angiotensin II (ANG II) receptor antagonist losartan on the blood-brain barrier (BBB) permeability in L-NAME-induced hypertension and/or in ANG II-induced acute hypertension in normotensive...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/s0024-3205(02)01772-1
更新日期:2002-07-12 00:00:00
abstract::These experiments were designed to test the hypothesis that cyclosporine A (CSA) inhibits renin secretion and stimulates renal prostaglandin E2 (PGE2) release in vitro. In rat renal cortical slices incubated at 37 degrees C in a buffered and oxygenated physiological saline solution containing 4 mM KCl, CSA concentrati...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(90)90187-v
更新日期:1990-01-01 00:00:00
abstract::The experiments were designed to study whether the inhibitors of the uptake of serotonin (5-HT) potentiated the prejunctional effects of 5-HT on peripheral sympathetic nerves. The effect of two selective 5-HT uptake inhibitors, citalopram and fluoxetine, were studied on the presynaptic actions of 5-HT in the cat isola...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(86)90438-8
更新日期:1986-07-07 00:00:00
abstract::In the present report we describe an NTPDase 1 (ATP diphosphohydrolase; ecto-apyrase; EC 3.6.1.5) in rat hippocampal slices. The effect of glutamate on the ATPase and ADPase activities in rat hippocampal slices of different ages was also studied since adenosine, the final product of an enzymatic chain that includes NT...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/s0024-3205(02)01621-1
更新日期:2002-05-31 00:00:00
abstract::Physalis angulata and P. peruviana are herbs widely used in folk medicine. In this study, the aqueous and ethanol extracts prepared from the whole plant of these species were evaluated for their antihepatoma activity. Using XTT assay, three human hepatoma cells, namely Hep G2, Hep 3B and PLC/PRF/5 were tested. The res...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/j.lfs.2003.09.058
更新日期:2004-03-05 00:00:00
abstract::Tricyclic antidepressant drugs bind to histamine receptors in rodent and other mammalian tissues. However, a readily accessible, normal human tissue for studies of these drugs has not been available. We showed that freshly isolated human leukocytes can be used for this purpose. Following isolation by dextran sedimenta...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(84)90441-7
更新日期:1984-12-17 00:00:00
abstract::A response in heat shock protein 70 (hsp 70) expression in the beta-naphthoflavone (BNF) treated rainbow trout (Oncorhynchus mykiss) corresponded to altered metabolic status of the liver as evidenced by the lower phosphoenolpyruvate carboxykinase (PEPCK), lactate dehydrogenase and 3-hydroxyacylcoA dehydrogenase activi...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/s0024-3205(97)00366-4
更新日期:1997-01-01 00:00:00
abstract::Human, dog and rabbit corpus cavernosum type 5 phosphodiesterases (PDE5) were isolated and their characteristics were compared. The three enzymes showed Km values of 0.8, 2.1 and 2.3 uM, respectively. They exhibited similar pH-dependence with optimal pH being 7.5. They required Mg++ for activity and the activity was s...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/s0024-3205(01)00989-4
更新日期:2001-03-16 00:00:00
abstract::Anandamide (arachidonylethanolamide; AEA) is an endogenous ligand for the cannabinoid receptor and its pharmacological effects are under intensive study. However, AEA has a low aqueous solubility and stability which may restrict its use and may eventually endanger the reliability of the obtained results. In the presen...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(96)00024-0
更新日期:1996-01-01 00:00:00
abstract::A new simplified procedure for determination of nitric oxide (NO) in biological solutions is described utilizing a new reducing system of nitric oxide prior to chemiluminescence. Advantages of the new method makes heating of the reducing solution unnecessary and avoids cooling and condensation of generated vapors. Onl...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(92)90625-y
更新日期:1992-01-01 00:00:00
abstract::Inhibitors of neuronal norepinephrine (NE) uptake are useful for the treatment of a variety of diseases including depression and urinary incontinence. In the present study, we synthesized and evaluated a novel analog of the potent and selective NE uptake inhibitor, nisoxetine. Thionisoxetine more potently inhibited th...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(95)00166-4
更新日期:1995-01-01 00:00:00
abstract::Involvement of cyclic AMP-dependent protein kinase in the desensitization of GABAB receptor expressed in Xenopus oocytes was studied. GABA produced an outward current in the presence of bicuculline, under voltage-clamp conditions. Baclofen mimicked the effect of GABA, thereby indicating that the response to GABA in th...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(95)02235-1
更新日期:1995-11-17 00:00:00
abstract::5-Bromo-2'-deoxyuridine (BrdU) has been recently found to enhance adrenal glucocorticoid secretion in rats. Since BrdU-labeling is today the most employed technique for assessing cell proliferation, we have investigated whether this side-effect of BrdU may influence mitotic activity (as evaluated by metaphase-arrested...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/s0024-3205(97)00439-6
更新日期:1997-01-01 00:00:00
abstract::Addition of a nitroxybutyl moiety to diclofenac greatly reduces its damaging effects on the gastric mucosa without altering its ability to suppress prostaglandin synthesis and exert anti-inflammatory actions. The present study was performed in order to determine if this derivative of diclofenac, called nitrofenac, wou...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(94)90083-3
更新日期:1994-01-01 00:00:00
abstract::In primary cultured bovine adrenal chromaffin cells (BACC), pituitary adenylate cyclase activating polypeptide 1-38 (PACAP) produced a dose related increase in tyrosine hydroxylase (TH) Vmax when measured 48 hours after the beginning of the treatment; a significant increase was observed with 0.5 nM and the maximal ind...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(94)00614-8
更新日期:1994-01-01 00:00:00
abstract::Much evidence has gathered that nitric oxide (NO) signaling, via cGMP-dependent mechanisms, may activate pro-survival pathways in hippocampal neurons and inhibit apoptosis. Past research has revealed that the enhancement of monoaminergic neurotransmission via exercise or treatment with antidepressant medications leads...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/j.lfs.2007.09.003
更新日期:2007-09-29 00:00:00
abstract::Effects of intracellular accumulation of isoproterenol (ISO) on lactate production were examined in perfused rat heart. The lactate production during ISO perfusion in rat heart was increased and subsequent addition of an inhibitor of catechol-O-methyl transferase (COMT) further enhanced the production, and the enhance...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(90)90284-x
更新日期:1990-01-01 00:00:00
abstract::Acute renal injury (AKI) is a risk factor for the development of hypertension, which involves oxidative stress, changes in Na+ handling, and the intrarenal renin-angiotensin-aldosterone system (RAAS) as underlying mechanisms. We investigated in rats whether renal ischemia-reperfusion (IR) leads to changes in the proxi...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/j.lfs.2020.118879
更新日期:2021-02-01 00:00:00
abstract::Fenfluramine, a drug that induces increased synaptic serotonin, was used to train Fawn-Hooded rats in a drug discrimination paradigm. This strain of rats is thought to possess a genetic serotonin storage abnormality. The intent of the study was to see if the Fawn-Hooded rat was similar or dissimilar to the more freque...
journal_title:Life sciences
pub_type: 杂志文章
doi:
更新日期:1997-01-01 00:00:00
abstract::Prolidase deficiency seems to be a rather rare metabolic disorder. However, many new cases can be detected because screening is easy to perform and enzymatic confirmation allows the differentiation from other iminodipeptidurias . Clinical symptoms are briefly reviewed, while biological considerations and prolidase pro...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(84)90363-1
更新日期:1984-05-21 00:00:00
abstract::LH stimulation is mediated by its own receptor at the first step of the cascade, after which intracellular cAMP increases to stimulate the transcription of steroidogenic acute regulatory protein (StAR) in mouse MA-10 Leydig tumor cells. StAR mediates the rate-limiting step of steroidogenesis, which is the transfer of ...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/s0024-3205(03)00698-2
更新日期:2003-10-17 00:00:00
abstract::The aggregation of melanin-granules within fish pigment cells (melanophores) can be elicited either by electrical stimulation of intrinsic nerves or by the addition of adrenergic agonists. The pigment aggregation seems to be mediated by alpha-2-adrenoceptors. In this investigation we have used various agonists and ant...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(85)90595-8
更新日期:1985-09-16 00:00:00
abstract::The compound (+)-MR200 [(+)-methyl (1R,2S)-2-{[4-(4-chlorophenyl)-4-hydroxypiperidin-1-yl]methyl}-1-phenylcyclopropanecarboxylate] is a sigma ligand with increased affinity and selectivity compared to the structurally related ligand haloperidol. From the results of a previous study on the modulation of a systemically ...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/j.lfs.2005.10.005
更新日期:2006-04-18 00:00:00
abstract:AIMS:Aristolochic acid (AA) nephrotoxicity is related to accumulation of methylglyoxal (MGO) and N(ε)-(carboxymethyl)lysine (CML) in the mouse kidney. We studied the activity of renal semicarbazide-sensitive amine oxidase (SSAO), a key enzyme involved in MGO generation, in AA-treated mice, and investigated nephroprotec...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/j.lfs.2014.07.034
更新日期:2014-09-26 00:00:00
abstract::In an effort to obtain highly potent glucagon antagonists, we have investigated glucagon (1) structure-function relationships utilizing the following design principles: (1) structural changes known to lead to partial agonist activities; (2) conformational restrictions; (3) changes in the conformational probabilities o...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(93)90513-3
更新日期:1993-01-01 00:00:00
abstract::The anticonvulsant effects and duration of protective action of midazolam against Metrazol induced seizures were studied in 528 rats aged 7,12,18,25 and 90 days. The doses of 0.025, 0.05, 0.25, 0.5 and 1.0 mg/kg were administered immediately before Metrazol (100 mg/kg in all but 18-day-old animals where 90 mg/kg were ...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(92)90421-k
更新日期:1992-01-01 00:00:00
abstract::Thalidomide (Thd) was given in two trials (total daily dose: 5 or 8 mg Thd/kg body weight, respectively) for five and three days to a healthy male volunteer, and various receptors were analyzed on white blood cells before, during and after (up to 30 days) the treatment period. There were neither marked deviations in t...
journal_title:Life sciences
pub_type: 杂志文章
doi:10.1016/0024-3205(92)90162-i
更新日期:1992-01-01 00:00:00