scholarly journals Phasic and Tonic Smooth Muscle Function of the Partially Obstructed Guinea Pig Intestine

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Jingbo Zhao ◽  
Donghua Liao ◽  
Jian Yang ◽  
Hans Gregersen
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Guinea Pigs ◽  
Muscle Function ◽  
Circumferential Stress ◽  
Outer Diameter ◽  
Dependent Manner ◽  
Contraction Force ◽  
Jejunal Segment ◽  
Smooth Muscle Function

This study was to generate phasic and tonic stress-strain curves for evaluation of smooth muscle function in the obstructed guinea pig jejunum. Partial and sham obstruction of the jejunum in guinea pigs was created surgically, with guinea pigs not being operated on served as normal controls. The animals survived 2, 4, 7, and 14 days, respectively. The jejunal segment was distended to 10 cm H2O. The pressure and outer diameter changes were recorded. Passive conditions were obtained by using papaverine. Total phasic, tonic, and passive circumferential stress and strain were computed from the diameter and pressure data with reference to the zero-stress-state geometry. The active phasic and tonic stresses were defined as the total phasic and tonic stress minus the passive stress. The thickness of intestinal muscle layers increased in a time-dependent manner after obstruction. The amplitude of passive, total phasic, total tonic, active phasic, and active tonic circumferential stresses increased as function of strain 7 days after obstruction. However, when normalized to muscle layer thickness, the amplitude of active stresses did not differ among the groups. In conclusion, the long-term-obstructed intestine exhibits increased total smooth muscle contraction force. However, the contraction force per smooth muscle unit did not increase.

Ontogeny of epithelial modulation of airway smooth muscle function in the guinea pig

1993 ◽  
Vol 15 (2) ◽  
pp. 105-110 ◽  
Author(s):  
W. Michael Southgate ◽  
Bruce E. Pichoff ◽  
Edward L. Stevens ◽  
Venkataraman Balaraman ◽  
Catherine F. T. Uyehara ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Airway Smooth Muscle ◽  
Muscle Function ◽  
Smooth Muscle Function

SMALL BOWEL ISCHEMIA/REPERFUSION (II/R) ALTERS COLONIC SMOOTH MUSCLE FUNCTION.

Shock ◽  
1998 ◽  
Vol 9 (Supplement) ◽  
pp. 13
Author(s):  
DT Dempsey ◽  
BS Myers ◽  
JP Ryan ◽  
J Carroll ◽  
SI Myers
Keyword(s):  
Smooth Muscle ◽  
Small Bowel ◽  
Muscle Function ◽  
Ischemia Reperfusion ◽  
Bowel Ischemia ◽  
Smooth Muscle Function

Effect of Flush-Perfusion on Vascular Endothelial and Smooth Muscle Function

1997 ◽  
Vol 64 (4) ◽  
pp. 1075-1081 ◽  
Author(s):  
Richard Ingemansson ◽  
Algimantas Budrikis ◽  
Ramunas Bolys ◽  
Trygve Sjöberg ◽  
Stig Steen
Keyword(s):  
Smooth Muscle ◽  
Muscle Function ◽  
Vascular Endothelial ◽  
Smooth Muscle Function

scholarly journals Effects of Scleroderma Antibodies and Pooled Human Immunoglobulin on Anal Sphincter and Colonic Smooth Muscle Function

2012 ◽  
Vol 143 (5) ◽  
pp. 1308-1318 ◽  
Author(s):  
Jagmohan Singh ◽  
Sidney Cohen ◽  
Vaibhav Mehendiratta ◽  
Fabian Mendoza ◽  
Sergio A. Jimenez ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Anal Sphincter ◽  
Muscle Function ◽  
Human Immunoglobulin ◽  
Smooth Muscle Function

scholarly journals Fundamental Roles of Axial Stretch in Isometric and Isobaric Evaluations of Vascular Contractility

2019 ◽  
Vol 141 (3) ◽  
Author(s):  
Alexander W. Caulk ◽  
Jay D. Humphrey ◽  
Sae-Il Murtada
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Muscle Function ◽  
Contractile Function ◽  
Contractile Activity ◽  
Comparison Of Methods ◽  
Axial Stretch ◽  
Smooth Muscle Function ◽  
In Vivo Loading

Vascular smooth muscle cells (VSMCs) can regulate arterial mechanics via contractile activity in response to changing mechanical and chemical signals. Contractility is traditionally evaluated via uniaxial isometric testing of isolated rings despite the in vivo environment being very different. Most blood vessels maintain a locally preferred value of in vivo axial stretch while subjected to changes in distending pressure, but both of these phenomena are obscured in uniaxial isometric testing. Few studies have rigorously analyzed the role of in vivo loading conditions in smooth muscle function. Thus, we evaluated effects of uniaxial versus biaxial deformations on smooth muscle contractility by stimulating two regions of the mouse aorta with different vasoconstrictors using one of three testing protocols: (i) uniaxial isometric testing, (ii) biaxial isometric testing, and (iii) axially isometric plus isobaric testing. Comparison of methods (i) and (ii) revealed increased sensitivity and contractile capacity to potassium chloride and phenylephrine (PE) with biaxial isometric testing, and comparison of methods (ii) and (iii) revealed a further increase in contractile capacity with isometric plus isobaric testing. Importantly, regional differences in estimated in vivo axial stretch suggest locally distinct optimal biaxial configurations for achieving maximal smooth muscle contraction, which can only be revealed with biaxial testing. Such differences highlight the importance of considering in vivo loading and geometric configurations when evaluating smooth muscle function. Given the physiologic relevance of axial extension and luminal pressurization, we submit that, when possible, axially isometric plus isobaric testing should be employed to evaluate vascular smooth muscle contractile function.

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