Thereafter, there is no seasonal increase in weight or change in morphology in either the testis or epididymis, and spermatogenesis occurs all year round. The tammar prostate develops between Days 25 and 60 postpartum and is largely under the influence of androgens and dihydrotestosterone. But there is a clear increase in weight of the adult prostate during the breeding season that is attributed to the seasonal fluctuation in plasma testosterone concentrations. It is interesting to note that the MTR hybridization signal was stronger in the adult prostate compared with the juvenile and pouch young. This suggests the presence of higher numbers of MTRs in the adult prostate compared with that of prepubertal animals and may limit the role of MT in the male reproductive tract to adults.
Archive for the ‘Prostate Gland’ Category
Although immunoreactive MT and OT have been reported in Leydig cells, within seminiferous tubules and in the dorsal portion of the prostate gland in some male marsupials, neither the tammar testis nor prostate gland synthesizes MT. MT has been extracted in microgram quantities from the pituitary of male tammars and possums, and its release in the latter species is stimulated by hypertonic stress and hemorrhage.
Concentrations of MTRs in the anterior and central portion of the prostate were considerably lower than those of MTRs in the myometrium but were comparable with receptor concentrations in other female tissues such as the median vagina and endometrium. As MTR transcripts were found only in the smooth muscle layers surrounding the urethral lumen and in the outer fibroelastic capsule, low MTR protein concentrations may be due to a dilution effect from the glandular tissue that makes up the bulk of the prostate. ventolin 100 mcg
Analysis of male reproductive tract tissues by RT-PCR demonstrated MTR transcripts in the prostate gland and epididymis, but not testis, of both adult and juvenile males. Transcripts were also detected in the prostate of pouch young aged between 4 and 5 mo. These findings are not in agreement with recent work in the marmoset monkey showing that OT receptor mRNA was strongly expressed in the adult testis but only weakly expressed in the epididymis, vas deferens, and prostate. Our data at the mRNA level were confirmed at the protein level by radioreceptor assays that showed a high-affinity MTR in the prostate, but not the testis, of the male tammar wallaby. We previously characterized an MTR with ligand-binding specificities similar to those of the eutherian OT receptor in the tammar myometrium. buy birth control online
We obtained a partial (588 bp) nucleotide sequence of a putative MTR cDNA in an Australian marsupial, the tam-mar wallaby, that showed high homology to eutherian OT receptors and low homology to vasopressin receptors. The 196-amino acid MTR fragment corresponds to the region extending from the II to the VI putative transmembrane domain in all eutherian OT receptor genes published. Our data highlight regions of highly conserved amino acids in the OT receptor gene that are important for its biological function. ventolin 100 mcg
Characterization of the MTR in Male Reproductive Tract Tissues
Scatchard plots of 125I-OTA binding to matched samples of adult tammar prostate and testis were linear, indicating a single class of binding site that was confirmed by analysis with the Ligand program. The mean binding affinities (Ka) were similar in the prostate (2.1 ± 0.18 L/nmol: mean ± SEM, n = 8) and testis (1.3 ± 0.4 L/nmol). The specificity of 125I-OTA binding was assessed by competitive displacement studies with various OT and vasopressin receptor agonists and antagonists (Fig. 5). In the prostate gland and myometrium, MT and OT showed relatively high and equal binding affinities for the 125I-OTA-binding site, whereas AVP, LVP, and MC had much lower binding affinities. proventil inhaler
No MTR transcripts were detected if water replaced the cDNA template in the PCR reaction. The lack of a positive signal in those prostate samples pretreated with RNase prior to the PCR reaction (data not shown) indicated that any PCR products arose from cDNA. Specificity was confirmed by sequence analysis and hybridization with a gene-specific internal oligonucleotide probe. Strong positive signals were observed in the myometrium, prostate, and epididymis of the adult tammar compared with weaker signals in equivalent tissues in the juvenile and pouch young males (Fig. 2b). A weak positive signal was also present in the testis. Cheap Diskus Advair