[Quantitative analyses of human prostatic alpha-adrenoceptors and effects of terazosin on the alpha-adrenoceptor activity].
The adrenergic alpha-1 and -2 adrenoceptors in human hypertrophied and non-hypertrophied prostatic adenomas were measured in the saturation experiment using 3H-prazosin and 3H-yohimbine. Not only alpha-1 adrenoceptor but also alpha-2 adrenoceptor were found to exist with great amount in prostatic adenomas. In the inhibition experiment selective alpha-1 antagonists, prazosin and terazosin inhibited the 3H-prazosin or 3H-yohimbine bindings to prostatic adenomas. The ability as alpha-1 antagonist is ten times greater in prazosin than in terazosin, but that as alpha-2 antagonist is greater in terazosin than in prazosin. These data suggest that terazosin may have other effects than the relaxation of prostatic smooth muscles in hypertrophied prostatic adenoma.
Morita
T
T
Department of Urology, Tokyo Medical and Dental University School of Medicine.
D000236:Adenoma / Q000378:metabolism; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000368:Aged; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009638:Norepinephrine / Q000037:antagonists & inhibitors; D011224:Prazosin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D011467:Prostate / Q000187:drug effects; D011470:Prostatic Hyperplasia / Q000188:drug therapy / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*; D015016:Yohimbine / Q000378:metabolism
D000317:Adrenergic alpha-Antagonists; D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; C041226:Terazosin; D009638:Norepinephrine; D011224:Prazosin