Expression of parathyroid-hormone- related protein in the partially obstructed rabbit bladder.
BACKGROUND
Parathyroid-hormone-related protein (PTHrP) is considered as an autocrine/paracrine regulator of growth and/or differentiation in normal and malignant tissues. We determined the distribution and density of the expression of PTHrP in the rabbit bladder during growth in response to partial outlet obstruction and its relation with the smooth muscle/collagen ratio.


METHODS
A total of 30 male New Zealand White rabbits were studied. After 7, 14, 28 or 56 days of obstruction, 6 rabbits per group were sacrificed and the bladder extracted. Six sham-operated rabbits served as controls. The expression and localization of PTHrP or collagen type III were detected by immunohistochemistry using specific antibodies.


RESULTS
The levels of PTHrP were progressively increased by 14 days of obstruction, whereas they decreased after 14 days, although the PTHrP positivity was higher than in sham controls by 28 and 56 days of obstruction. PTHrP staining was related to the smooth muscle/collagen ratio, both showing a peak in rabbits obstructed for 14 days.


CONCLUSIONS
These data indicate that PTHrP may play an important regulatory role in the cellular and vascular response to partial outlet obstruction.
Perez-Martinez
Francisco C
FC
Fundación Conchita Rabago, Albany, NY, USA.
Mannikarottu
Anita
A
Guven
Ahmet
A
Chichester
Paul
P
Juan
Yung-Shun
YS
Lin
Wei-Yu
WY
Levin
Robert M
RM
D000818:Animals; D005347:Fibroblasts / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D009130:Muscle, Smooth / Q000378:metabolism*; D044162:Parathyroid Hormone-Related Protein / Q000096:biosynthesis*; D011817:Rabbits; D013997:Time Factors; D016896:Treatment Outcome; D001743:Urinary Bladder / Q000378:metabolism*; D001748:Urinary Bladder Neck Obstruction / Q000378:metabolism / Q000473:pathology; D014563:Urodynamics
D044162:Parathyroid Hormone-Related Protein