Abstract:
:Vascular smooth muscle tone is regulated primarily by the sarcoplasmic free Ca2+ concentration, which determines the level of myosin phosphorylation. Stimulation of the muscle results in an increase in free [Ca2+], whereupon Ca2+ binds to calmodulin, inducing a conformational change enabling calmodulin to interact with and activate myosin light chain kinase. The active Ca2+.calmodulin.myosin light chain kinase complex catalyses the phosphorylation of serine-19 of the two 20-kDa light chains of myosin; this triggers cross-bridge cycling and the development of force. Relaxation follows restoration of free [Ca2+] to the resting level, whereupon calmodulin dissociates from myosin light chain kinase, which is thereby inactivated, and myosin is dephosphorylated by myosin light chain phosphatase and remains detached from actin. Overwhelming evidence now exists in favour of the central role of myosin phosphorylation-dephosphorylation in smooth muscle contraction-relaxation. However, considerable evidence supports the existence of additional, secondary mechanisms that can modulate the contractile state of smooth muscle either by altering the Ca2+ sensitivity of the contractile response or otherwise modulating one of the molecular events occurring downstream of the Ca2+ signal, e.g., the interaction of phosphorylated myosin heads with actin. The interplay of several regulatory elements confers on the contractile response of vascular smooth muscle the high degree of flexibility and adaptability required for the effective regulation of blood pressure.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Walsh MPdoi
10.1139/y94-130subject
Has Abstractpub_date
1994-08-01 00:00:00pages
919-36issue
8eissn
0008-4212issn
1205-7541journal_volume
72pub_type
杂志文章,评审abstract::Using the glycogen depletion technique, we have examined utilization of specific fibre types during prolonged submaximal exercise to investigate the recruitment pattern employed by the central nervous system to sustain force generation in the face of a progressive glycogen depletion. Six male subjects (Vo2 max, 52.8 +...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-208
更新日期:1990-10-01 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
abstract::Steady state glucose kinetics were measured in 19 premature and 16 full-term piglets. Bodyweight, plasma glucose concentration, total body glucose turnover rate, and glucose pool size were not significantly different between the two groups. This suggests that the premature piglet is capable of maintaining glucose home...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y81-163
更新日期:1981-10-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-069
更新日期:1989-05-01 00:00:00
abstract::The present research was to assess the relationship between ABCB1 (G2677T/A, C3435T) polymorphisms and lipid homeostasis as well as risk of liver injury induced by atorvastatin in in-patients from China. The lipid levels (total cholesterol, high-density lipoprotein, triglycerides) as well as metabolic enzymes of hepar...
journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-388
更新日期:1987-12-01 00:00:00
abstract::The effects of 5-hydroxytryptamine (5-HT) on spinal motoneurons were examined in pentobarbital-anaesthetized cats and in nonanaesthetized decerebrate cats by intracellular recording and extracellular iontophoresis of 5-HT. 5-HT first induced a depolarization and then a long-lasting hyperpolarization (up to 60 min) wit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:1991-02-01 00:00:00
abstract::The effect of high potassium depolarization on the release of exogenously supplied [3H]glutamate and endogenous glutamate from tissue slices of the cestode Hymenolepis diminuta was examined. Increasing concentrations of potassium stimulated the release of radiolabel from tissues preloaded with [3H]glutamate. This rele...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-145
更新日期:1988-07-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-049
更新日期:1980-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-168
更新日期:1986-07-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y09-008
更新日期:2009-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-053
更新日期:1986-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y2012-099
更新日期:2012-10-01 00:00:00
abstract::Diazinon (DZN) is a common organophosphorus insecticide extensively used for agriculture and veterinary purposes. DZN toxicity is not limited to insects; it also induces harmful effects in mammals and birds. Our experiment evaluated the protective and antioxidant potential of sesame oil (SO) and (or) alpha-lipoic acid...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2015-0131
更新日期:2016-01-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y04-038
更新日期:2004-06-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:
更新日期:2000-03-01 00:00:00
abstract::The reported efficiencies of drug encapsulation into liposomes range from less than 0.1% to more than 10% per micromole phospholipid, depending on the nature of the drug and of the liposome employed. We have sought to investigate some of the factors which control the efficiency of drug encapsulation. We have found tha...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y79-081
更新日期:1979-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-126
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/Y11-007
更新日期:2011-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-262
更新日期:1992-01-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-083
更新日期:1988-04-01 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-75-4-255
更新日期:1997-04-01 00:00:00
abstract::To determine if increased endometrial vascular permeability (a response which precedes decidualization) could be obtained in temporally nonsensitized uteri by treatments designed to increase endometrial adenosine 3':5'-cyclic monophosphate (cAMP) concentrations, cholera toxin (an activator of adenylate cyclase) was in...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-172
更新日期:1985-09-01 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
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更新日期:2012-06-01 00:00:00
abstract::The level of circulating triacylglycerols is determined by the balance between their delivery into the plasma and their removal from it. Plasma triacylglycerols are derived either from dietary fat as chylomicrons or from endogenous hepatic synthesis as very low density lipoproteins. Their removal occurs through the ac...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y91-242
更新日期:1991-11-01 00:00:00
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::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
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更新日期:2015-03-01 00:00:00
abstract::The freezing point and the melting point of myoplasm were measured with two experimental models. In all samples, a supercooled stage was reached by lowering the temperature of the sample to approximately - 7 degrees C, and the freezing of the sample was mechanically induced. The freezing process was associated with a ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-167
更新日期:1983-10-01 00:00:00
abstract::Cerebrocrast is a novel lipophilic dihydropyridine derivative with potential neuroprotective and antidiabetic properties. We have analyzed its interaction with L-type (CaV1.2b) and T-type (CaV3.1) calcium channels using a whole-cell patch clamp in HEK 293 cells. Cerebrocrast inhibited current flux through both CaV1.2b...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y09-086
更新日期:2009-11-01 00:00:00
abstract::Several experimental data document an activation of the mitogen-activated protein kinases Erk1 and Erk2 by bradykinin (BK), an agonist of the kinin B2 receptor (B2R). In contrast, other reports showed an inhibitory modulation of mitogenesis by BK. Therefore, we explored in the isolated glomeruli the effect of B2R acti...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y02-033
更新日期:2002-04-01 00:00:00