Contractile properties of urethral smooth muscles of young and aged female dogs: morphological and pharmacological aspects.
Int J Urol
; 7(8): 298-306, 2000 Aug.
Article
em En
| MEDLINE
| ID: mdl-10976818
ABSTRACT
BACKGROUND:
Alpha1-adrenoceptors are highly concentrated in the urethral smooth muscles and may play an important role in the contraction of this area. However, detailed examinations of age-related changes of the properties of urethral smooth muscle have rarely been undertaken.METHODS:
The contractile properties of urethras from young non-parous and old parous female beagles were determined with a urethral function study, macroscopic autoradiography for urethras using [3H]-labeled tamsulosin and morphometry of the urethral muscles.RESULTS:
The antagonistic effect (pA2) of prazosin for norepinephrine was 7.76+/-0.13 in young dogs and 7.62+/-0.06 in aged dogs. The specific binding of [3H]-tamsulosin (a relatively selective alpha1A-adrenoceptor antagonist) was recognized diffusely in proximal urethras with in vitro autoradiography. The density of binding in smooth muscles was approximately 60 and 40% in circular longitudinal layers, respectively, for both dogs.CONCLUSIONS:
The female canine urethra had alpha1A, and alpha1L-adrenoceptors. No age-related changes were seen in the function of the proximal urethra, distribution of alpha1-adrenoceptor binding sites and smooth muscle densities.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Uretra
/
Envelhecimento
/
Contração Muscular
/
Músculo Liso
Limite:
Animals
Idioma:
En
Revista:
Int J Urol
Assunto da revista:
UROLOGIA
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
Japão