Effect Of Qiangshengubenkeli On CGRP And Mrna Protein Expression Of Nos Isoform In Corpus Cavernous Body Of Castrated Rats

To study the long-term effica-cy of qiangshengubenkeli(QSKL)on erectile dysfunction(ED) and the pharmaceutical action mechanism, the effects of the herb on the CGRP and expression of mRNA and protein of NOS isoforms(nNOS)in corpus cavernous(CC) body of castrated rats ED after long-term oral administration were investigated.Many researches indicated that nitric oxide (NO), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), substance P are main neurotransmitters for penile erection. Some studies have revealed the dependence of mRAN expression of nitric oxide synthase (NOS) and VIP on androgen in rat penis, so far no study has investigated whether protein expression of CGRP in rat penis is regulated by androgen, including testosterone (T) and dihydrotestosterone (DHT), or whether CGRP is dependent on T or DHT. In this research, on the basis of our animal models, the effect of androgen on protein expression of CGRP of SD rats was studied. METHODSThe study was conducted on 120 male Sprague-Dawley (SD) rats (10 weeksold, body weight 320±20g). Rats were maintained in alternating cycles. Food and water were freely available. Rats were randomly divided into 6 groups: 120 Wistar rats were ran-domly divided into 6 groups. Group A(Normal),B(castrated),C(castrated but given testosterone undecanoat 25 mg/kg per 4 weeks by intramuscular injection), D(Bigherb).E(Midherb) F(smallherb). ED animal model was constructed by surgically removes of testis and Herb and normal saline was orally administrated for 10 weeks. Serum free testosterone wasmeasured by ELISA analysis. Group A. Normal. Group B. castrated. Group C. castrated. Treated with testosterone undecanoate 25mg/kg/4 weeks. Intramuscular injection Group D. castrated treated with big QSKL.Group E. Castrated treated with middle QSKL. Grop F. castrated treated with small QSKL.Five and ten weeks after treatments with Qiangshengubenkeli(QSKL) described above, half of rats were killed under the condition of intraperitoneal injection of ketamine (35mg/kg). During the operation blood samples were taken for the measurements of testosterone (T) and dihydrotestosterone (DHT) by radioimmunoassay. Penis samples were stored under10% formaldehyde (for the second part of the research). Paraffin-embedded tissue sections of the rat penis were stained with antibodies against CGRP Using Envision System immunohistochemical technique. Those nerve fibers whose colors were stained to be brown-yellow were identified to be CGRPpositive nerve fibers. At 200 magnification of Sight microscopy, computer assisted quantitative image analysis system was used to count the mean areas of CGRP positive nerve fibers and CGRP negative nerve fibers of 10 randomly selected fields of each section. So as to count the percent of CGRP positive nerve fibers area.The expression of mRNA and protein of NOS isoforms(nNOS) in CC of rats were detected by RT-PCR and immunohistochemical staining.SPSS12.0 for windows (Statistical Product and Service solution.SPSS) were used, if P<0.05. it means that difference between two groups is significant. RESULTS1 The level of serum free testosterone was decreased significantly in castrated rats (P<0. 05).QSKL has significant influence on the level of serum free testosterone (P<0. 05).The expression of mRNA and protein of nNOS and iNOS in CC of castrated rats were decreased significantly(P<0. 05), However, eNOS was not expressed. The expression of mRNA and protein of nNOS and iNOS in CC of castrated rats increased significantly after oral administration of QSKL for ten weeks compared with placebo, but no obvious influence on eNOS expression in CC.2.There was significant difference of the percent of CGRP positive nerve fibers area between group A. C. D. E and groupB, F in 5 weeks model (P<0. 05)3. After 10 weeks, the group A, D^ E percent of CGRP positive nerve fibers area of control group was significant higher than that of group B, C,F (P<0. 05)4.In the experimental groupA^ C, E, F.the percent of CGRP positive nerve fibers area in each 5 weeks model was...