29 research outputs found
Ontogeny and regulation of variant thyroid hormone receptor isoforms in developing rat testis
High affinity-low capacity nuclear triiodothyronine (T 3) receptors (TR(s)), identified as a product of c-erbA(α) proto-oncogene, are expressed in prepubertal rat Sertoli cell. At this age, exogenous T 3 treatment as well as hypothyroidism affects Sertoli cell functions. We examined the ontogenetic expression pattern of TR(s) in the rat testis. Northern analysis confirms that TR(s) are expressed at high level from fetal development until prepubertal period. RNase protection analysis demonstrates that TR(α2), the variant isoform of TR(α1), is constitutively expressed at all ages, while TR(α3) is absent in the adult gonad. While TR(α1) and TR(α2) expression declines during development, Rev-erbA(α) (Rev), the antisense mRNA encoded by the same c-erbA(α) genomic locus, increases beginning 5 days after birth and maximizing in adulthood. TR(α1), TR(α2), and Rev mRNA(s) do not appear to be directly regulated by thyroid hormone in testis; however, short-term neonatal hypothyroidism leads to the expression of TR(α1) and its variant in adult testis, which is absent in control coeval animals. Thus, during development of rat testis, the levels of messages of genes encoded in the c-erbA(α) genomic locus have different ontogenetic control. The ontogenetic profile of TR(α1) and its variant isoforms within the seminiferous epithelium suggests that these receptors are involved in the differentiation of the male gonad. (J. Endocrinol. Invest. 22: 843-848, 1999) (C)1999 Editrice Kurtis
Prevalence of chronic prostatitis in men with premature ejaculation.
OBJECTIVES: To investigate the prevalence of chronic prostatitis in men with premature ejaculation. The etiology of premature ejaculation is currently considered psychological in nature. However, the possibility that urologic, hormonal, or neurologic factors may contribute to this condition should be considered in its management.
METHODS: We evaluated segmented urine specimens before and after prostatic massage and expressed prostatic secretion specimens from 46 patients with premature ejaculation and 30 controls by bacteriologic localization studies. The incidence of premature ejaculation in the subjects with chronic prostatitis was also evaluated.
RESULTS: Prostatic inflammation was found in 56.5% and chronic bacterial prostatitis in 47.8% of the subjects with premature ejaculation, respectively. When compared with the controls, these novel findings were statistically significant (P <0.05).
CONCLUSIONS: Considering the role of the prostate gland in the mechanism of ejaculation, we suggest a role for chronic prostate inflammation in the pathogenesis of some cases of premature ejaculation. Since chronic prostatitis has been found with a high frequency in men with premature ejaculation, we stress the importance of a careful examination of the prostate before any pharmacologic or psychosexual therapy for premature ejaculation
Ontogenetic pattern of thyroid hormone receptor expression in the human testis
We studied the spatiotemporal distribution of thyroid hormone nuclear receptors (TRs) alpha1 and alpha2 and beta messenger RNA (mRNA) levels in normal human testicular tissue during development and in adulthood. Nonpathological specimens from five aborted fetuses (17 and 23 weeks of gestation, three and two cases, respectively) and from four patients undergoing orchiectomy (18 months old and 38-, 42-, and 52-yr-old, respectively) were analyzed by Northern blot, semiquantitative RT-PCR amplification using DNA sequences or specifically designed primers for the TR isoforms, and in situ hybridization. By using PCR amplification, we found that TRalpha1 and TRalpha2 are both expressed at different levels in fetal and adult testis. At all ages TRalpha2 is found at higher levels. Northern analysis showed hybridization signals corresponding to the expression of TRalpha2 and TRalpha in a ratio that increased from 2.6 at 17 weeks of gestation to 12.0 in adulthood. In fact, the expression of TRalpha1 dramatically decreased throughout development, being faintly detectable in the adult testis. Expression of TRbeta was not detected at any age studied. This finding was further confirmed by PCR, which did not amplify TRbeta either in fetal or in adult testis mRNAs. In situ hybridization studies showed the absence of TRbeta and that TRalpha1 and TRalpha2 colocalized in Sertoli cells of prepubertal testis, whereas germ and interstitial cells appeared devoid of TR mRNA signals. From these results it can be concluded that the human testis exclusively expresses TRalpha, which is localized in Sertoli cells, TRbeta being always undetectable. Fetal and prepubertal ages represent the period of maximal expression of TRalpha1 and TRalpha2. The alpha2/alpha1 ratio rises dramatically after development. These results confirm a critical window for the action of thyroid hormone in human testis, in the period of maximal expression of T3 binding isoform TRalpha1, and may account for the macroorchidism without virilization occurring when hyposecretion of thyroid hormones occurs before puberty
Is acupuncture a therapeutic option for premature ejaculation?
In the past, premature ejaculation (PE) has been considered a psychogenic condition, treated with psychotherapy. Our growing understanding of PE pathophysiology has increased the scientific community's interest in a symptom that is seen across many sexual pathologies. Is it possible to approach PE with traditional medicine approaches, such as acupuncture