In vivo experiments for the evaluation of α1-adrenoceptor antagonistic effects of SGB-1534 on canine urethra

Prostatic α1-adrenoceptors and uroselectivity

“…Although different protocols may be employed, the most commonly used species is the anesthetized dog, in which intraprostatic pressure changes can be measured and related to hemodynamic changes [81][82][83][84]. There is an excellent correlation between selectivity data derived from radioligand binding and the dog model [84].…”

The role of α1‐adrenoceptors and 5‐HT1A receptors in the control of the micturition reflex in male anaesthetized rats

“…Evidence suggests that this contraction is mediated by α 1 ‐adrenoceptors. For example, α 1 ‐adrenoceptor agonists increase intraurethral pressure and contract the isolated urethra ( Taniguchi et al ., 1996 ; Nishimatsu et al ., 1999 ) while antagonists at the α 1 ‐adrenoceptor, such as doxazosin and prazosin, inhibit contractions of the prostate and urethra induced by phenylephrine or hypogastric nerve stimulation in the anaesthetized rat, rabbit and dog ( Imagawa et al ., 1989a , 1989b ; Kenny et al ., 1994 ; Guilmard et al ., 1996 ; Suzuki et al ., 2000 ). In conscious rats, α 1 ‐adrenoceptor antagonists reduce baseline urethral pressure ( Martin et al ., 1995 ; 1997 ) and, in the conscious dog, doxazosin, terazosin and tamsulosin block increases in urethral pressure induced by phenylephrine ( Brune et al ., 1996 ).…”