Changes Of α₁-Adrenoceptor Subtypes MRNA Content And Norepinephrine Content In Human Benign Prostatic Hyperplasia Concomitant With Hypertension

Background and purposeBenign prostatic hyperplasia （BPH） is a common disease of middle-aged men,can cause difficulty urinating、urinary retention and even lead to renal failure,hypertension also is a common disease of middle-aged men. BPH and hypertensionoften troubled the quality of life of older men over the age of60, approximately25%of BPH patients merger hypertension. Foreign studies have shown that the symptomsof hypertension in BPH patients with hypertension was increased with the types ofantihypertensive drugs, in the BPH patients with hypertension group, IPSS wassignificantly higher than simple BPH group, maximum flow rate was significantlylower than simple BPH group, hypertension aggravated LUTS symptoms of BPH,tension and anxiety caused by LUTS can increased hypertension, the treatment ofBPH with hypertension has become a difficulty of clinical.Aging and the androgen has been the risk factors of BPH, the etiology of BPH isstill not very clear, a lot of data showing that increased excitability of the sympatheticnervous system is the correlation between BPH and hypertension, more and moreevidence show that the sympathetic nervous excitement can be used as an independentfactor of the causes of BPH other than androgen, the cause of hypertension is due toexcessive sympathetic nerve ending neurotransmitter release, increased sympatheticactivity may be the common pathogenesis of the BPH and hypertension.This study was designed to detect changes of three kinds of adrenoceptorsubtypes and changes of the content of norepinephrine in patients with BPH prostatetissue, to observe the impact of hypertension on BPH, and clarify the commonpathogenesis of BPH and hypertension to guide clinical treatment. Method47fresh specimens of BPH tissue were obtained by transurethral resection, andwere divided into simple BPH group of23cases and BPH with hypertension group of24cases, the diagnosis of hypertension was according to clinical criteria and the bloodpressure was controlled well. RT-PCR was used to determine the amount of α_1A、α_1B、α_1Dadrenoceptor subtypes mRNA and ELISA was used to determine the content ofnorepinephrine in each BPH tissue specimen.To observe the change of the expressionof adrenoceptor-1subtypes of prostate by the change of sympathetic activity.ResultIn all47specimens, the predominant subtype mRNA was α_1Aadrenoceptor, themRNA amount of α_1A、α_1B、α_1Dadrenoceptor subtypes were0.95±0.22,0.97±0.16,1.00±0.28（P>0.05） and the proportion of them was32.4%:33.1%:34.5%,respectively. Between simple BPH group and BPH with hypertension group, themRNA amount of α₁receptor and α_1Breceptor subtype were no difference, but α_1Aand α_1Dreceptor subtypes mRNA amount were changed. In BPH with hypertensiongroup, the amount of3subtypes mRNA were1.06±0.16,0.95±0.14,0.84±0.17（P<0.05） and the proportion was37.1%:33.4%:29.5%. The amount of α_1AsubtypemRNA was dominant and higher than simple BPH group （P<0.05）. In simple BPHgroup, the amount of3subtypes mRNA were0.83±0.22,0.98±0.18,1.19±0.27（P<0.05） and the proportion was27.7%:32.7%:39.4%. The amount of α_1DsubtypemRNA was dominant and higher than BPH with hypertension group （P<0.05）. Thecontent of norepinephrine in the prostate tissue of the group of simply BPH group is81.21±31.94ng/g, The content of norepinephrine of the group of BPH withhypertension is210.42±42.73ng/g, The content of norepinephrine in the prostatetissue of the group of BPH with hypertension is greater than simply BPHgroup（P<0.05）. ConclusionCompared to simple BPH group, the sympathetic activity was increased in thewith hypertension BPH group. The three kinds of adrenoceptor-1receptor subtypesare all expressed in the prostate tissue, there is no great difference of the expression ofthree kinds of adrenoceptor receptor subtypes. It was found that, in the simple BPHgroup, the expression proportion of the α_1Aadrenoceptor subtypes does not takeadvantage of other adrenoceptor-1receptor subtypes, the expression of α_1Dsubtypewas dominant. The amount of α_1A-adrenoceptor subtype mRNA in the BPH withhypertension group was significantly increased, we can assume that increasedsympathetic activity leading to increased of the α_1A-adrenoceptor subtype mRNA inthe prostate tissue. By the neurotransmitter norepinephrine, the sympathetic nervoussystem cause the prostatic smooth muscle contraction, which illustrates that the LUTSin patients of BPH with hypertension was more serious than simple BPH patients inthe molecular aspects. In this study, we can think that the sympathetic activity in theBPH with hypertension was greater, in performance of the enhancement of theexpression of α_1A-adrenoceptor subtype mRNA, focus on blocking α_1A-adrenoceptorsubtype function may be more beneficial to the clinical treatment of BPH patientsconcomitant with hypertension.