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 connexins in mouse Leydig cells that could be required for steroidogenesis. A reverse transcription - polymerase chain reaction screen involving isolated adult Leydig cells identified connexin36 and connexin45 as expressed along with connexin43. Treatment of dissociated testes with carbenoxolone, a nonspecific blocker of gap junctional coupling, significantly reduced testosterone output as did treatment with quinine, which disrupts coupling provided by connexin36 and connexin45 gap junctions but not those composed of connexin43, indicating that either or both of connexins 36 and 45 could be involved in supporting Leydig cell steroidogenesis. Immunolabeling of adult mouse testis sections confirmed the localization of connexin36 along with connexin43 in Leydig cell gap junctions but not connexin45, which is distributed throughout the cells. It was concluded that connexin36, connexin43, and connexin45 are coexpressed in Leydig cells with connexins 36 and 43 contributing to gap junctions. The role of connexin45 remains to be elucidated.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Li D,Sekhon P,Barr KJ,Márquez-Rosado L,Lampe PD,Kidder GMdoi
10.1139/cjpp-2012-0385subject
Has Abstractpub_date
2013-02-01 00:00:00pages
157-64issue
2eissn
0008-4212issn
1205-7541journal_volume
91pub_type
杂志文章abstract：:This study evaluated the in vitro expression of bone-related proteins by osteoblasts in the presence of different concentrations of human recombinant bone morphogenetic protein-2 (rhBMP-2). Immortalized human fetal osteoblastic cell line 1.19 (hFOB) were exposed to different concentrations of rhBMP-2 (10, 50, or 100 n...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2013-0080
更新日期：2013-11-01 00:00:00
abstract：:Previous studies have demonstrated that the D-enantiomer of isoidide dinitrate (IIDN) is 10-fold more potent than the L-enantiomer for relaxation and cyclic GMP accumulation in isolated rat aorta. To test whether preferential biotransformation of D-IIDN to a species that activates guanylate cyclase is the basis for th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-225
更新日期：1989-11-01 00:00:00
abstract：:The ability of dystrophic hamsters to maintain their body temperature despite abnormal muscle and brown adipose tissue, two organs involved in thermoregulation, was evaluated. Dystrophic hamsters (CHF 146) between the ages of 30 and 160 days kept at 21 degrees C had core (rectal) temperatures (TR) that were 0.5-1.5 de...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y85-187
更新日期：1985-09-01 00:00:00
abstract：:The purpose of this article is to review the current state of knowledge of ethanol neurobehavioural teratogenesis and its postulated mechanisms. The review comprises an examination of ethanol teratogenesis in the human, including the fetal alcohol syndrome, and in experimental animals. Several current proposed mechani...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y95-173
更新日期：1995-09-01 00:00:00
abstract：:Single-channel recordings from central neurons of the helix snail, Cepaea nemoralis, revealed two types of channels that could be activated by stretch (i.e., by the membrane deformation produced when suction is applied to the patch pipette). One, a K+ channel (58 pS in physiological solution), was evident in excised a...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y92-025
更新日期：1992-02-01 00:00:00
abstract：:We investigated potential sex differences in bone resorption and the conservation of whole body bone mass in 24-week-old Sprague-Dawley rats maintained on a 1.0% calcium diet and then fed diets containing 0.02, 0.5, 1.0, or 1.75% calcium for 31 days. Lowering dietary calcium from 1.00% to 0.02% doubled whole skeleton ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2001-05-01 00:00:00
abstract：:Electrophysiological studies were performed on slowly adapting cells of the crayfish (Astacus astacus) stretch receptor to examine some aspects of the operation of the sodium pump. Intracellular sodium activity (aiNa) and pH (pHi) were measured with liquid ion exchanger microelectrodes and the effects of NH3/NH+4 were...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y87-028
更新日期：1987-02-01 00:00:00
abstract：:The purpose of this study was to investigate whether Ca2+ -Mg2+ ATPase in the distal tubule (where calcium transport is active, against a gradient, and hormone dependent) presents some characteristics different from those observed in the proximal tubule, and whether these characteristics are likely to shed light on th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y87-328
更新日期：1987-10-01 00:00:00
abstract：:The systemic and inotropic properties of prostaglandin E1 (PGE1) were investigated in 20 unanesthetized dogs. Pairs of ultrasonic dimension gauges and a micromanometer were implanted in the subendocardium and the apex of the left ventricle (LV), respectively. Seven to ten days later, increasing doses of PGE1 were infu...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y84-249
更新日期：1984-12-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y84-105
更新日期：1984-06-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y83-159
更新日期：1983-09-01 00:00:00
abstract：:We have previously demonstrated a direct relationship between the activity of the arachidonic acid cascade in vivo and the extent of cellular damage following several types of experimental injury. Since phospholipase activity has been shown to regulate arachidonic acid availability, we tested the ability of circulatin...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y81-198
更新日期：1981-12-01 00:00:00
abstract：:The aim of the present study was to investigate the protective effect of total flavones of rhododendra (TFR) pharmacological preconditioning against myocardial ischemia-reperfusion (I/R) injury and its probable mechanisms in rats. Rat myocardial I/R injury was induced by ligating and untying the left anterior descendi...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y08-016
更新日期：2008-03-01 00:00:00
abstract：:The risk assessment of mycotoxins is made up of two major components: an exposure assessment and a hazard assessment. There are many uncertainties in both of these components. This paper will briefly discuss the various aspects of the risk assessment process as it applies to mycotoxins and will then focus mainly on so...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y90-155
更新日期：1990-07-01 00:00:00
abstract：:Chronically elevated plasma norepinephrine has the potential for supporting function of diseased hearts, yet may also initiate harmful biochemical and (or) structural changes in the myocardium. The present study investigated the dosage-related effects of chronic norepinephrine infusion on markers of myocardial damage ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y86-161
更新日期：1986-07-01 00:00:00
abstract：:The effects of localized distension of the pulmonary vein - left atrial junctions on plasma arginine vasopressin (AVP) have been examined in chloralose anaesthetized dogs. Pulmonary vein distension caused an increase in heart rate and a decrease in plasma AVP concentration. Cooling the vagosympathetic nerves to 10 deg...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y83-136
更新日期：1983-08-01 00:00:00
abstract：:The effects of lithium chloride on ornithine decarboxylase (ODC) activity were compared in the adrenal and kidney of control (saline treated) and prolactin-treated rats. ODC activity was decreased in kidney of both groups of animals, the magnitude of the effect of lithium in the hormone-treated group varying with the ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y92-180
更新日期：1992-09-01 00:00:00
abstract：:The mechanisms of the positive inotropic action of a new synthetic tetrahydroisoquinoline compound, SL-1, were investigated in isolated rat cardiac tissues and ventricular myocytes. SL-1 produced a rapidly developing, concentration-dependent positive inotropic response in both atrial and ventricular muscles and a nega...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y95-727
更新日期：1995-11-01 00:00:00
abstract：:The effects of modafinil on heat thermoregulatory responses were studied in 10 male subjects submitted to a sweating test after taking 200 mg of modafinil or placebo. Sweating tests were performed in a hot climatic chamber (45 degrees C, relative humidity <15%, wind speed = 0.8 m x s(-1), duration 1.5 h). Body tempera...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 临床试验,杂志文章
doi：10.1139/y02-092
更新日期：2002-08-01 00:00:00
abstract：:The combined effect of a beta 2-antagonist and an alpha 2-agonist on the release of adrenal catecholamines was studied in the anaesthetized and vagotomized dog. The electrical stimulation of the splanchnic nerve (5-V pulses of 2 ms duration for 3 min at a frequency of 3 Hz) produced a significant rise in adrenal catec...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-219
更新日期：1988-10-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y85-179
更新日期：1985-09-01 00:00:00
abstract：:Two principles suffice to model the large-scale geometry of normal human coronary arterial networks. The first principle states that artery diameters are set to minimize the power required to distribute blood through the network. The second principle states that arterial tree geometries are set to globally minimize th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2000-08-01 00:00:00
abstract：:Epinephrine caused hyperglycemia in part by increasing gluconeogenesis. However, the mechanism of its gluconeogenic effects has not been studied in ruminants. This study was undertaken to examine the effect of epinephrine on the net hepatic uptake of selected glucose precursors in sheep. The major abdominal blood vess...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y91-071
更新日期：1991-04-01 00:00:00
abstract：:Bacterial toxins are widespread in the environment as well as in the digestive system of humans and animals. Toxin from Gram-negative bacteria (endotoxin or lipopolysaccharide; LPS) has a life-long programming effect on reproduction in rats, but the mediators have not been well-documented, so we investigated the effec...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2014-0559
更新日期：2015-08-01 00:00:00
abstract：:Amiodarone is a new antiarrhythmic drug, commonly coadministered with digoxin in various cardiac disorders. Amiodarone caused a 10-fold increase of serum digoxin in rats, when the two drugs were simultaneously administered. Amiodarone significantly reduced digoxin uptake by renal cortical slices in the rat, and failed...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y83-212
更新日期：1983-12-01 00:00:00
abstract：:Radioactively labelled microspheres (15 micron diameter) were used to measure cardiac output (CO) distribution and blood flows in spleen, kidneys, and skeletal muscle before and after normovolemic anemia or polycythemia in anesthetized rats. Hematocrits were changed from 45 to 33% or from 45 to 59% by an exchange tran...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y80-069
更新日期：1980-04-01 00:00:00
abstract：:Ablation of the anteroventral third ventricle (AV3V) region, which includes the organum vasculosum laminae terminalis (OVLT), blocks the febrile response of guinea pigs to systemically injected endotoxin; by contrast, discrete lesions of the OVLT transiently enhance fever in rabbits and rats. To assess whether separat...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y87-200
更新日期：1987-06-01 00:00:00
abstract：:Airway smooth muscle (ASM) contraction controls the airway caliber. Airway narrowing is exaggerated in obstructive lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD). The mechanism by which ASM tone is dysregulated in disease is not clearly understood. Recent research on ion channels, parti...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/cjpp-2014-0417
更新日期：2015-03-01 00:00:00
abstract：:The purpose of this study was to characterize the biological activity of the synthetic rat growth hormone releasing factor analogue rGRF(1-29)NH2 and to compare its action on growth hormone (GH) release to that of authentic rGRF(1-43)OH. We first compared the concentration-response characteristics of the two peptides ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y91-026
更新日期：1991-02-01 00:00:00
abstract：:Resting membrane potentials and membrane conductances of chick skeletal muscle in culture were determined from the 3rd to the 10th day after plating. The effect of tetraethylammonium (TEA) and of replacement of potassium with caesium on these parameters was investigated. Resting membrane potential (Em) rises during my...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y80-100
更新日期：1980-06-01 00:00:00
