Structure and mechanics of growing arterial microvessels from hypertrophied urinary bladder in the rat
(1994) In Pflügers Archiv 426(6). p.506-515- Abstract
- Rat bladder hypertrophy, induced by a partial ligation of the urethra, was used to study the accompanying changes of microvascular smooth muscle mechanics, pharmacology and morphology. A segment of a microarterial vessel to the bladder was taken from a defined anatomical location and studied in a wire myograph in vitro at the length for maximal isometric force development (Lmax). After 10 days of ligation, bladder hypertrophy resulted in a microvascular growth response compared to non-operated controls which was characterized by (i) an increase of the calculated diameter at Lmax from 134 +/- 5 microns to 222 +/- 19 microns; (ii) an increase of the media thickness from 22.4 +/- 1.9 microns to 32.2 +2- 3.0 microns; (iii) an increase of the... (More)
- Rat bladder hypertrophy, induced by a partial ligation of the urethra, was used to study the accompanying changes of microvascular smooth muscle mechanics, pharmacology and morphology. A segment of a microarterial vessel to the bladder was taken from a defined anatomical location and studied in a wire myograph in vitro at the length for maximal isometric force development (Lmax). After 10 days of ligation, bladder hypertrophy resulted in a microvascular growth response compared to non-operated controls which was characterized by (i) an increase of the calculated diameter at Lmax from 134 +/- 5 microns to 222 +/- 19 microns; (ii) an increase of the media thickness from 22.4 +/- 1.9 microns to 32.2 +2- 3.0 microns; (iii) an increase of the active tension from 1.42 +/- 0.28 mN/mm to 3.06 +/- 0.33 mN/mm; (iv) no change of the wall/lumen ratio (from 0.83 +/- 0.10 to 0.79 +/- 0.15). Normalized length/force relations (active, passive and total) did not differ significantly between microarteries from control and hypertrophic bladders. Microvascular smooth muscle growth was also associated with a decreased sensitivity to K(+)-induced depolarization and an increased sensitivity to alpha 1-adrenergic stimulation. No differences were noted regarding the Ca2+ sensitivity of force during K(+)-induced depolarization. The results suggest that microvascular growth (1) is immediately and positively influenced by the organ growth; (2) results in a functional resetting of the microvascular segments towards larger diameters without gross morphological or mechanical alterations; and (3) is accompanied by pharmacological alterations of the smooth muscle reactivity. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1108523
- author
- Boels, P J ; Arner, Anders LU ; Malmqvist, Ulf LU and Uvelius, Bengt LU
- organization
- publishing date
- 1994
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Phenylephrine, K+ Sensitivity, Ca2+ Sensitivity, Length/force relation, Smooth muscle
- in
- Pflügers Archiv
- volume
- 426
- issue
- 6
- pages
- 506 - 515
- publisher
- Springer
- external identifiers
-
- pmid:8052520
- scopus:0028344779
- ISSN
- 0031-6768
- DOI
- 10.1007/BF00378528
- language
- English
- LU publication?
- yes
- id
- 9212ff01-fed8-4a63-81e2-86e8b5d1eddd (old id 1108523)
- date added to LUP
- 2016-04-01 16:53:11
- date last changed
- 2021-12-23 08:14:46
@article{9212ff01-fed8-4a63-81e2-86e8b5d1eddd, abstract = {{Rat bladder hypertrophy, induced by a partial ligation of the urethra, was used to study the accompanying changes of microvascular smooth muscle mechanics, pharmacology and morphology. A segment of a microarterial vessel to the bladder was taken from a defined anatomical location and studied in a wire myograph in vitro at the length for maximal isometric force development (Lmax). After 10 days of ligation, bladder hypertrophy resulted in a microvascular growth response compared to non-operated controls which was characterized by (i) an increase of the calculated diameter at Lmax from 134 +/- 5 microns to 222 +/- 19 microns; (ii) an increase of the media thickness from 22.4 +/- 1.9 microns to 32.2 +2- 3.0 microns; (iii) an increase of the active tension from 1.42 +/- 0.28 mN/mm to 3.06 +/- 0.33 mN/mm; (iv) no change of the wall/lumen ratio (from 0.83 +/- 0.10 to 0.79 +/- 0.15). Normalized length/force relations (active, passive and total) did not differ significantly between microarteries from control and hypertrophic bladders. Microvascular smooth muscle growth was also associated with a decreased sensitivity to K(+)-induced depolarization and an increased sensitivity to alpha 1-adrenergic stimulation. No differences were noted regarding the Ca2+ sensitivity of force during K(+)-induced depolarization. The results suggest that microvascular growth (1) is immediately and positively influenced by the organ growth; (2) results in a functional resetting of the microvascular segments towards larger diameters without gross morphological or mechanical alterations; and (3) is accompanied by pharmacological alterations of the smooth muscle reactivity.}}, author = {{Boels, P J and Arner, Anders and Malmqvist, Ulf and Uvelius, Bengt}}, issn = {{0031-6768}}, keywords = {{Phenylephrine; K+ Sensitivity; Ca2+ Sensitivity; Length/force relation; Smooth muscle}}, language = {{eng}}, number = {{6}}, pages = {{506--515}}, publisher = {{Springer}}, series = {{Pflügers Archiv}}, title = {{Structure and mechanics of growing arterial microvessels from hypertrophied urinary bladder in the rat}}, url = {{http://dx.doi.org/10.1007/BF00378528}}, doi = {{10.1007/BF00378528}}, volume = {{426}}, year = {{1994}}, }