Abstract:
:Neuronal factors co-released with neurotransmitters may play an important role in synapse development and function. Calcitonin gene related peptide (CGRP) and adenosine 5'-triphosphate (ATP), two principal neuromodulators present in the motor nerve terminals, were studied for their roles and mechanisms during early development of neuromuscular synapses in Xenopus nerve--muscle co-cultures. CGRP treatment increased the decay time and amplitude of spontaneous synaptic currents (SSCs) recorded from innervated myocytes, without affecting SSC frequency, suggesting a postsynaptic mechanism. ATP also increased the SSC amplitude and decay time. In addition, ATP was shown to potentiate the responses of isolated myocytes to iontophoretically applied acetylcholine (ACh). Single-channel recording from isolate myocytes showed that both CGRP and ATP specifically increased the open time of embryonic-type, low-conductance ACh channels. Pharmacological experiments suggest that the CGRP actions were mediated by cAMP-dependent protein kinase (PKA), while ATP exerted its effects by binding to P2 purinoceptors and thereby activating protein kinase C (PKC). Moreover, the effects of CGRP and ATP on ACh channel activity were restricted to immature myocytes. Taken together, these results suggest that endogenous CGRP and ATP co-released with ACh from the nerve terminal may promote synaptic development by potentiating postsynaptic ACh channel activity during the early phase of synaptogenesis.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Lu B,Fu WMdoi
10.1139/y95-149subject
Has Abstractpub_date
1995-07-01 00:00:00pages
1050-6issue
7eissn
0008-4212issn
1205-7541journal_volume
73pub_type
杂志文章,评审abstract::The role that thromboxane A2 plays in contractions induced by leukotriene D4 in guinea-pig isolated lung parenchyma was investigated under equilibrium conditions. Lung tissue generated thromboxane A2 and prostacyclin spontaneously as evidenced by the slow accumulation of their biologically inactive metabolites, thromb...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-230
更新日期:1987-07-01 00:00:00
abstract::Lectins, known to recognize endothelial cell adhesion molecules, have been shown to release endothelium-derived relaxing factor (EDRF) from blood vessels. We investigated the effects of different leukocyte-type cells to determine if these cells, by interacting with the endothelium, could release EDRF from the circumfl...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y95-052
更新日期:1995-03-01 00:00:00
abstract::N,N-Diethyl-2-(1-pyridyl)ethylamine (E-2-P) produced 59 +/- 7% of the maximal response to histamine in guinea pig ileal longitudinal smooth muscle and antagonized the responses of this tissue to histamine. The estimated binding constant of E-2-P for the histamine receptor predicted a binding curve nearly coincident wi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-198
更新日期:1980-11-01 00:00:00
abstract::Nonalcoholic fatty liver disease (NAFLD) is a spectrum of chronic liver conditions that are characterized by steatosis, inflammation, fibrosis, and liver injury. The global prevalence of NAFLD is rapidly increasing in proportion to the rising incidence of obesity and type 2 diabetes. Because NAFLD is a multifaceted di...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-2016-0681
更新日期:2017-10-01 00:00:00
abstract::Connexin43 has been recognized as forming gap junctions in Leydig cells. However, previous work has shown that mouse Leydig cells lacking this connexin do not suffer any limitation of their ability to produce testosterone when stimulated with luteinizing hormone. The objective of this study was to identify additional ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2012-0385
更新日期:2013-02-01 00:00:00
abstract::The endothelium, although only a single layer of cells lining the vascular and lymphatic systems, contributes in multiple ways to vascular homeostasis. Subsequent to the 1980 report by Robert Furchgott and John Zawadzki, there has been a phenomenal increase in our knowledge concerning the signalling molecules and path...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y2012-073
更新日期:2012-06-01 00:00:00
abstract::High buffer cardioplegia may provide protection against ischemic damage by reducing the extent of intracellular acidosis. Secondary cardioplegia may improve postischemic recovery by restoration of high energy phosphates, ionic gradients, and intracellular pH. To test these hypotheses, pig hearts were arrested with hig...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y91-260
更新日期:1991-11-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y05-067
更新日期:2005-08-01 00:00:00
abstract::Rapamycin, a new antifungal antibiotic, was found to inhibit the immune response in rats. It totally prevented the development of two experimental immunopathies (experimental allergic encephalomyelitis (EAE) and adjuvant arthritis (AA)) and the formation of humoral (IgE-like) antibody. It was about half as potent as c...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y77-007
更新日期:1977-02-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-234
更新日期:1985-11-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-268
更新日期:1985-12-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2019-0015
更新日期:2019-11-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y06-014
更新日期:2006-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-019
更新日期:1988-02-01 00:00:00
abstract::The development of cardiac hypertrophy was examined in rats given ethanol in a nutritionally adequate, liquid diet mixture, by intubation, in severely intoxicating doses at 8-h intervals for up to 96 h, alone or in combination with prazosin. Other groups of rats received isocalorically paired quantities of maltose-dex...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-040
更新日期:1989-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-044
更新日期:1982-03-01 00:00:00
abstract::Changes in electrical potential difference and sodium-potassium ATPase activity of rectal mucosa in dogs were examined before and after jejunal-ileal bypass surgery. The potential difference in the postoperative period was significantly higher (P less than 0.05) than the preoperative value. The potential difference in...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-078
更新日期:1983-05-01 00:00:00
abstract::Changes in metabolic characteristics of the liver and jejunal epithelia as a result of feeding the beta-agonist albuterol to chickens for 3 and 6 weeks were studied. Feeding albuterol resulted in a change in weights of the liver and small intestines. Chickens fed albuterol for 6 weeks had greater levels of plasma none...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-069
更新日期:1989-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:2001-08-01 00:00:00
abstract::Significant tension development resulting from the administration of lanthanum salts (La3+) to isolated aorta tissues was observed in preparations from the spontaneously hypertensive rat (SHR) but not in preparation from age-matched normotensive Wistar rats (NWR). The response to La3+ was significantly greater in tiss...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:1977-10-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-170
更新日期:1992-09-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-134
更新日期:1987-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-149
更新日期:1986-06-01 00:00:00
abstract::We found when L-type calcium current (ICa-L) was recorded with the perforated patch-clamp method in rat ventricular myocytes that bath application of phenylephrine (with propranolol) evoked a biphasic response characterized by an initial transient suppression followed by a sustained potentiation. The transient suppres...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y05-058
更新日期:2005-11-01 00:00:00
abstract::We tested the effects of inhibiting the carbonic anhydrase activity of rat soleus and extensor digitorum longus muscles on the isometric contractile properties and the resistance to fatigue. SOL and EDL muscles from female rats were incubated in vitro in the presence of methazolamide, a specific inhibitor of carbonic ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-103
更新日期:1989-06-01 00:00:00
abstract::Space travelers experience anorexia and body weight loss in a microgravity environment, and microgravity-like situations cause changes in hypothalamic activity. Hypothalamic melanocortins play a critical role in the regulation of metabolism. Therefore, we hypothesized that microgravity affects metabolism through alter...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y09-074
更新日期:2009-10-01 00:00:00
abstract::In urethane-anaesthetized rats, ion-selective microelectrodes recorded changes in extracellular K+ and Ca2+ concentrations (delta[K+]omicron and delta[Ca2+]omicron) in pyramidal layers of the hippocampus (mostly in area CA1), which were evoked by fimbrial-commissural stimulation. [K+]omicron increased linearly with fr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-243
更新日期:1982-12-01 00:00:00
abstract::Normal mammalian sexual maturation and reproductive functions require the integration and precise coordination of hormones at the hypothalamic, pituitary, and gonadal levels. Hypothalamic gonadotropin-releasing hormone (GnRH) is a key regulator in this system; after binding to its receptor (GnRHR), it stimulates de no...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:
更新日期:2000-12-01 00:00:00
abstract::The effects of U46619, a thromboxane mimic, on cytosolic Ca2+ concentration and platelet aggregation were determined in human platelets. Cytosolic Ca2+ concentration was determined by Quin-2 fluorescence and platelet aggregation quantitated with an aggregometer. Addition of U46619 (1 x 10(-7) M) to the platelet suspen...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y91-088
更新日期:1991-05-01 00:00:00
abstract::The purpose of the present investigation was to determine the nature of the functional interaction of muscarinic agonists with cAMP-generating and cAMP-independent agonists in left atria. Negative inotropic responses of rabbit isolated left atrial strips to the muscarinic agonist carbachol were measured in the absence...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-099
更新日期:1986-05-01 00:00:00