Faculty Bibliography

PURPOSE: We determined the tissue localization of the alpha 1a-adrenoceptor in the human prostate. MATERIALS AND METHODS: Autoradiographic localization of the alpha 1a-adrenoceptor in the human prostate was determined by performing competitive displacement experiments on slide mounted tissue sections using the ligand 125iodine-2-(-[4-hydroxyphenyl]-ethyl-aminomethyl)tetralone (125I-Heat), and the alpha 1-antagonists WB-4101 (4 x 10(-8) M.) and 5-carboxamido-2,6-diethyl-1,4-dihydro-3-[N-(3-[4-hydroxy-4-phenylpipe ridin- yl]propyl)]carboxamido-4-(4-nitrophenyl) (SNAP 5272, 3 x 10(-7) M.). Under these experimental conditions, WB-4101 and SNAP 5272 are selective alpha 1a/alpha 1d-adrenoceptor and alpha 1a-adrenoceptor antagonists, respectively. The autoradiographs were quantitatively analyzed using a computer image analysis system. RESULTS: Specific 125I-Heat binding associated with the epithelium and stroma were independently analyzed. WB-4101 and SNAP 5272 inhibited 100% of the specific 125I-Heat binding in the stroma, suggesting that all of the stromal alpha 1-adrenoceptors are of the alpha 1a subtype. WB-4101 inhibited none of the specific 125I-Heat binding in the epithelium, suggesting that the alpha 1-adrenoceptor in the epithelium is of the alpha 1b subtype. SNAP 5272 displaced only 25% of the specific 125I-Heat binding in the epithelium, suggesting that a relatively small percentage of the epithelial alpha 1-adrenoceptor is of the alpha 1a subtype. CONCLUSIONS: To our knowledge, our study represents the first cellular localization of the alpha 1-adrenoceptor subtypes in the human prostate using highly selective alpha 1-adrenoceptor antagonists and is consistent with the physiological observation that the activity of prostatic smooth muscle is mediated by the alpha 1a-adrenoceptor

PURPOSE/OBJECTIVE:We assessed the relationship between changes in scores for the American Urological Association (AUA) symptom index and benign prostatic hyperplasia (BPH) impact index with patient global ratings of improvement in a large Veterans Affairs trial comparing different pharmacological therapies for BPH. MATERIALS AND METHODS/METHODS:The primary analyses compared absolute score changes from baseline with global ratings of improvement at 13 weeks for 1,218 men. RESULTS:Subjects who rated themselves as being slightly improved had a mean decrease in AUA symptom index and BPH impact index scores of 3.1 and 0.4 points, respectively. However, the baseline scores strongly influenced this relationship. CONCLUSIONS:These data provide guidance for investigators using the AUA symptom index and BPH impact index as outcome measures.

1. To examine the presence of nitric oxide synthase (NOS) activity in female dog urethra, pharmacological experiments were performed using electrical field stimulation (EFS), guanethidine, atropine, NG-nitro-L-arginine methyl ester and L-arginine, NOS immunohistochemistry using specific anti-NOS antibody, and reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining were also performed. 2. EFS caused frequency-dependent contractions in all urethral preparations, but in the presence of guanethidine and atropine, EFS caused significant relaxation in the proximal urethra and was without effect on the distal urethra. 3. In the presence of guanethidine, atropine, and NG-nitro-L-arginine methyl ester, small contractions to EFS were re-established in the proximal urethra, but not in the distal urethra. NG-nitro-D-arginine methyl ester had no such effect. 4. In the presence of guanethidine, atropine, and NG-nitro-L-arginine methyl ester, the addition of L-arginine, restored the EFS-elicited relaxant responses previously seen with guanethidine and atropine alone in the proximal urethra (at 30 Hz; 12.89 +/- 5.27% to -2.44 +/- 4.43%, mean +/- s.e., P < 0.05). D-Arginine had no such effect. 5. In the distal urethra, the addition of NG-nitro-L-arginine methyl ester and then L-arginine had no effect on responses to EFS in preparations treated with guanethidine and atropine. 6. Sodium nitroprusside caused relaxation in both the proximal and distal urethra. The relaxant responses per cm2 cross sectional area in the proximal and distal urethra were 1.23 +/- 0.29, and 2.02 +/- 0.54 g cm-2 cross sectional area (mean +/- s.e.), respectively: there was no significant difference between them. 7. Both NOS and NADPH diaphorase-positive neurones were present in dog urethra, the densities of both being higher in the proximal urethra than in the distal urethra. 8. These results show that female dog urethra possesses NOS nerves and that endogenous NO may play a role in relaxation in the proximal but not the distal urethra.

PURPOSE: We attempt to determine whether terazosin is effective therapy for the treatment of prostatism-like symptoms in women. MATERIALS AND METHODS: A total of 29 women 47 to 79 years old with prostatism-like symptoms entered a randomized double-blind study comparing terazosin (14) versus placebo (15). The salient inclusion and exclusion criteria consisted of an American Urological Association (AUA) symptom score of 8 or more, post-void residual volume less than 300 ml. and absence of stress urinary incontinence. RESULTS: The baseline and final visit AUA symptom scores were 12.7 and 10.7 respectively, in the placebo group, and 16.4 and 13.6, respectively, in the terazosin group. The differences between the change in AUA symptom score in the placebo and terazosin groups were not clinically or statistically significant. CONCLUSIONS: Our study demonstrates that terazosin is not effective for the treatment of prostatism-like symptoms in aging women

Randomized double-blind placebo controlled studies have consistently demonstrated the safety and effectiveness of selective alpha 1 blockers for the treatment of clinical BPH. Selective alpha 1 blockers relieve the symptoms of prostatism and decrease bladder outlet obstruction. The advantages of this class of drugs for the medical treatment of BPH include the extremely rapid onset of action, statistically and clinically significant effects on relevant outcome measures, adverse experiences that are generally infrequent, mild, and reversible, serum PSA levels are not affected, and hypertension is also effectively treated. The long-term effectiveness of selective alpha 1 blockers has recently been reported. Prostate smooth muscle tension is mediated by the alpha 1a (previously defined as alpha 1c) AR. The pharmaceutical industry is aggressively pursuing development of alpha 1a 'prostate' selective AR antagonists

The treatment of BPH has changed dramatically over the last decade. Industry has recognized the potential market for BPH therapies. Urologists have accepted and embrace the development of alternative treatment strategies. The combined resources and talents of industry and academic urology will lead to exciting future advances in this field. The optimal treatment of BPH requires not only new technology but a better understanding of the pathophysiology and natural history of this disease. Urologists are presently engaged in studies to better define these fundamental aspects of the disease process. The end result of these investigative efforts will be to the advantage of patients afflicted with BPH

The pathophysiology of clinical BPH has been attributed to bladder outlet obstruction resulting from the enlarged prostate. A direct relationship does not exist between prostate size, symptom severity, or bladder outlet obstruction. The pathophysiology of prostatism is most likely multifactorial. Elucidating the factors contributing to symptoms will likely provide the foundation for the development of new pharmacological alternatives for the medical treatment of BPH