Testicular vasomotion (rhythmical variations in testicular blood flow) was studied in adult rats using laser Doppler flowmetry. Vasomotion was not present in testes in which the Leydig cells had been destroyed, but it could be induced by a low dose of testosterone. Transposition of a scrotal testis into the abdominal cavity inhibited vasomotion and this was apparently not caused by Leydig cell malfunction. Depletion of specific germ cells (by unilateral X-irradiation induced killing of spermatogonia and maturation depletion of germ cells) did not abolish vasomotion in the testis. It is suggested that testicular vasomotion is influenced by testosterone and by factors from Sertoli cells.
O. Colin, A. Bergh, J-E. Damber and A. Widmark
Joanna Cartwright, W Colin Duncan, Hilary O D Critchley and Andrew W Horne
Ectopic pregnancy remains a considerable cause of maternal morbidity and mortality worldwide. Currently, it is diagnosed using a combination of transvaginal ultrasound and serial serum β-human chorionic gonadotrophin levels. Diagnosis is often delayed and these tests are time-consuming and costly, both psychologically to the patient and financially to health services. The development of a biomarker that can differentiate a tubal ectopic from an intrauterine implantation is therefore important. In the pre-genomic era, a one-by-one scientific approach has revealed over 20 candidate biomarkers that could be used as a test to diagnose ectopic pregnancy although at present their clinical utility is very limited. These biomarkers cluster into themes: markers of abnormal embryo/trophoblast growth, markers of abnormal corpus luteum function, markers of a growing pregnancy in the Fallopian tube, markers of inflammation and peritoneal irritation, and uterine markers of normal implantation. It is likely that this thematic approach will facilitate the identification of newer biomarkers using microarray technology and inform the development of investigative paradigms using multiple markers at the time of presentation.
Cheryl J Ashworth, Charis O Hogg, Cindy W F Hoeks, Ramona D Donald, W Colin Duncan, Alistair B Lawrence and Kenny M D Rutherford
This study assessed the effect of pre-natal social stress and post-natal pain on the reproductive development of young (approximately day 40) pigs. Male pigs carried by sows that were stressed by mixing with unfamiliar older sows for two 1-week periods during mid-pregnancy had lower plasma testosterone (0.54 vs 0.86 ng/ml, s.e.d.=0.11; P=0.014) and oestradiol (E2; 22.9 vs 38.7 pg/ml, s.e.d.=7.80; P=0.021) concentrations compared with males carried by unstressed control sows. Although there was no effect of pre-natal stress on female E2 concentrations, female pigs carried by stressed sows had fewer primordial ovarian follicles (log −4.32/μm2 vs −4.00/μm2, s.e.d.=0.136; P=0.027). Tail amputation on day 3 after birth reduced E2 concentrations in female (4.78 vs 6.84 pg/ml, s.e.d.=0.86; P=0.03) and in male (25.6 vs 34.9 pg/ml, s.e.d.=3.56; P=0.021) pigs and reduced both testis weight (0.09% of body weight vs 0.10% of body weight, s.e.d.=0.003; P=0.01) and the percentage of proliferating Leydig cells (1.97 vs 2.12, s.e.d.=0.114; P=0.036) compared with sham-amputated littermate controls. There was a significant (P=0.036) interaction between the effects of pre-natal stress and post-natal pain on testicular expression of the steroidogenic enzyme 17α-hydroxylase, such that amputation increased expression in pigs born to control sows, but reduced expression in animals born to stressed sows. This study shows that stressful procedures associated with routine animal husbandry can disrupt the developing reproductive axis.