Reproductive performance of male mice after hypothalamic ghrelin administration

It has been demonstrated that food intake and reproductive physiology are both simultaneously modulated to optimize reproductive success under fluctuating metabolic conditions. Ghrelin (GHRL) is an orexigenic peptide identified as the endogenous ligand of the growth hormone secretagogue receptor that is being investigated for its potential role on reproduction. Considering that data available so far are still limited and characterization of GHRL action mechanism on the reproductive system has not been fully elucidated, we studied the participation of hypothalamus in GHRL effects on sperm functional activity, plasma levels of gonadotropins and histological morphology in mice testes after hypothalamic infusion of 0.3 or 3.0 nmol/day GHRL or artificial cerebrospinal fluid (ACSF) at different treatment periods. We found that GHRL 3.0 nmol/day administration for 42 days significantly reduced sperm concentration (GHRL 3.0 nmol/day = 14.05 ± 2.44 × 10⁶/mL vs ACSF = 20.33 ± 1.35 × 10⁶/mL, P < 0.05) and motility (GHRL 3.0 nmol/day = 59.40 ± 4.20% vs ACSF = 75.80 ± 1.40%, P < 0.05). In addition, histological studies showed a significant decrease percentage of spermatogonia (GHRL 3.0 nmol/day = 6.76 ± 0.68% vs ACSF = 9.56 ± 0.41%, P < 0.05) and sperm (GHRL 3.0 nmol/day = 24.24 ± 1.92% vs ACSF = 31.20 ± 3.06%, P < 0.05). These results were associated with a significant reduction in luteinizing hormone and testosterone plasma levels (P < 0.05). As GHRL is an orexigenic peptide, body weight and food intake were measured. Results showed that GHRL increases both parameters; however, the effect did not last beyond the first week of treatment. Results presented in this work confirm that central GHRL administration impairs spermatogenesis and suggest that this effect is mediated by inhibition of hypothalamic-pituitary-gonadal axis.

Pregnancy outcomes in women with polycystic ovary syndrome in two Latin American populations

Pregnancy complications and obstetric outcomes were compared in 80 Chilean (PPCOS_Ch) and 70 Argentinian (PPCOS_Ar) pregnant women. Reference groups of Chilean and Argentinian normal pregnant women from the same antenatal care units were also compared. PPCOS_Ch showed a higher prevalence of gestational diabetes mellitus (GDM) (OR, 2.28, 95% CI: 1.08-4.77, p = .030) and a lower prevalence of pregnancy-induced hypertension (PIH) (OR, 0.20, 95% CI: 0.07-0.54, p = .001) compared to PPCOS_Ar. In the normal pregnant groups, the prevalence of PIH was lower in Chilean women compared to Argentinian women (OR, 0.24, 95% CI: 0.10-0.62, p = .001). Similar to the pattern observed in the normal populations, newborns from PPCOS_Ch had higher birth weight and length compared with the newborns of PPCOS_Ar (p = .006 and .014, respectively). In conclusion, differences in pregnancy complications and obstetric outcomes between Chilean and Argentinian pregnant women with PCOS could be determined by ethnic diversity together with environmental factors of both populations. Impact Statement What is already known on this subject: The reproductive and metabolic phenotypes of women with polycystic ovary syndrome vary between different populations, which could significantly influence the obstetric and neonatal outcomes in this syndrome. What the results of this study add: Pregnant women with PCOS from two Latin American countries (Chile and Argentina) exhibit differences in the prevalence of gestational diabetes and pregnancy-induced hypertension, and in the birth weight of their newborns. What the implications are of these findings for clinical practice and/or further research: Ethnic diversity together with environmental factors are fundamental elements that must be considered in the management of pregnant women with PCOS.

Reduced vasopressin receptors activation mediates the anti-depressant effects of fluoxetine and venlafaxine in bulbectomy model of depression

RATIONALE

In response to stress, corticotropin releasing hormone (CRH) and vasopressin (AVP) are released from the hypothalamus, activate their receptors (CRHR1, CRHR2 or AVPr1b), and synergistically act to induce adrenocorticotropic hormone (ACTH) release from the anterior pituitary. Overstimulation of this system has been frequently associated with major depression states.

OBJECTIVE

The objective of the study is to assess the role of AVP and CRH receptors in fluoxetine and venlafaxine effects on the expression of depression-related behavior.

METHODS

In an animal model of depression (olfactory bulbectomy in mice, OB), we evaluated the effects of fluoxetine or venlafaxine (both 10 mg/kg/day) chronic administration on depression-related behavior in the tail suspension test. Plasma levels of AVP, CRH, and ACTH were determined as well as participation of their receptors in the expression of depression related-behavior and gene expression of AVP and CRH receptors (AVPr1b, CRHR1, and CRHR2) in the pituitary gland.

RESULTS

The expression of depressive-like behavior in OB animals was reversed by treatment with both antidepressants. Surprisingly, OB-saline mice exhibited increased AVP and ACTH plasma levels, with no alterations in CRH levels when compared to sham mice. Chronic fluoxetine or venlafaxine reversed these effects. In addition, a significant increase only in AVPr1b gene expression was found in OB-saline.

CONCLUSION

The antidepressant therapy used seems to be more likely related to a reduced activation of AVP rather than CRH receptors, since a positive correlation between AVP levels and depressive-like behavior was observed in OB animals. Furthermore, a full restoration of depressive behavior was observed in OB-fluoxetine- or venlafaxine-treated mice only when AVP was centrally administered but not CRH.

[Polycystic ovary sindrome: impact on reproductive and maternal fetal health]

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism (H), oligo-anovulation (O) and / or polycystic ovaries (P). There is currently little information on perinatal complications.

OBJECTIVE

to investigate obstetric and neonatal characteristics of women with PCOS in our population.

MATERIAL AND METHODS

we studied 87 pregnant women with PCOS (categorized in four phenotypes according Rotterdam Consensus: A (H + O + P) n = 53; B (H + O) n = 9; C (H + P) n = 16 and D (O + P) n = 9) and 96 without PCOS (control). We analyzed clinical and biochemical features (age, anthropometry hirsutism, acanthosis nigricans, OGTT, insulin, lipid profile, androgen and gonadotropins) during preconception, (weight gain, blood pressure, OGTT) through gestation and occurrence of perinatal complications.

RESULTS

we found no differences in age (29.4 ± 4 and 28.7 ± 5 years) and body mass index (28.2 ± 6 and 27.8 ± 6 kg / m2) in both groups; while patients with PCOS had higher waist circumference, blood pressure and acanthosis nigricans versus control. Despite similar weight gain, patients with PCOS had higher percentage of perinatal complications. In the A phenotype RR for perinatal adverse outcomes was 2.37 (95%CI: 1.67-3.36, p <0.001). The HOMA-IR index preconception and fasting glucose during pregnancy were the predictors for these complications (p=0.01).

CONCLUSION

patients with PCOS have a higher risk for complications during pregnancy and newborns more frequently have low weight or macrosomy. A careful history can recognize patients with higher perinatal risk to develop complications.

Role of ghrelin in fertilization, early embryo development, and implantation periods

In order to clarify the physiological role of ghrelin in gestation, we evaluated the effects of administration of exogenous ghrelin (2 or 4 nmol/animal per day) or its antagonist (6 nmol/animal per day of (d-Lys3)GHRP6) on fertilization, early embryo development, and implantation periods in mice. Three experiments were performed, treating female mice with ghrelin or its antagonist: i) starting from 1 week before copulation to 12 h after copulation, mice were killed at day 18 of gestation; ii) since ovulation induction until 80 h later, when we retrieved the embryos from oviducts/uterus, and iii) starting from days 3 to 7 of gestation (peri-implantation), mice were killed at day 18. In experiments 1 and 3, the antagonist and/or the highest dose of ghrelin significantly increased the percentage of atrophied fetuses and that of females exhibiting this finding or a higher amount of corpora lutea compared with fetuses (nCL/nF) (experiment 3: higher nCL/nF-atrophied fetuses: ghrelin 4, 71.4-71.4% and antagonist, 75.0-62.5% vs ghrelin 2, 46.2-15.4% and control, 10-0.0%; n=7-13 females/group; P<0.01). In experiment 2, the antagonist diminished the fertilization rate, and both, ghrelin and the antagonist, delayed embryo development (blastocysts: ghrelin 2, 62.5%; ghrelin 4, 50.6%; and antagonist, 61.0% vs control 78.4%; n=82-102 embryos/treatment; P<0.0001). In experiment 3, additionally, ghrelin (4 nmol/day) and the antagonist significantly diminished the weight gain of fetuses and dams during pregnancy. Our results indicate that not only hyperghrelinemia but also the inhibition of the endogenous ghrelin effects exerts negative effects on the fertilization, implantation, and embryo/fetal development periods, supporting the hypothesis that ghrelin (in 'adequate' concentrations) has a physiological role in early gestational events.

The impact of obesity on male reproduction: its biological significance

Since obesity and male subfertility have increased in parallel during the last decades, the hypothesis of an association between these two phenomena has been explored by several researchers. Although there is no consensus apparently obesity impacts men's reproductive potential by several mechanisms, like alterations on the hypothalamus-pituitary-testicular axis, modifications of spermatogenesis and semen quality and/or impairment of men's sexual health. This review intends to summarize the underlying bases of such alterations and propose new ones, without miscalculating their biological significance. Obesity is not rigorously related to subfertility; in addition, the existence of a genetic predisposition to obesity-linked sterility is currently under investigation. Nonetheless, the impact of obesity on male reproductive potential must be fully elucidated since the prevalence of obesity is increasing and consequently, the number of obese men with reduced fertility will also rise.

[Polycystic ovary syndrome: physiopathology review]

Polycystic ovary syndrome (PCOS), the most common gynecological endocrinopathy in women of reproductive age, is characterized by hyperandrogenism, chronic anovulation and /or polycystic ovaries. Although the cause of PCOS is still unknown, there are several hypotheses attempting to explain the primary defect; the most commonly accepted is insulin resistance. Due to its high prevalence, the patients have increased risk of developing metabolic and cardiovascular alterations. The compensatory hyperinsulinemia contributes to hyperandrogenism in different ways: by stimulating ovarian androgen synthesis and inhibiting hepatic production of sex hormone binding globulin. From the study of the intrauterine environment in recent years it has been suggested that PCOS may have an origin in utero associated with prenatal exposure to androgens. The aim of this paper is to review the main mechanisms proposed to cause the syndrome.

Differential effects of fluoxetine and venlafaxine on memory recognition: possible mechanisms of action

Serotonin-specific reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI) are antidepressant drugs commonly used to treat a wide spectrum of mood disorders (Wong and Licinio, 2001). Although they have been clinically used for more than 50 years, the molecular and cellular basis for the action of SSRIs and SNRIs is not clear. Considering that the changes in gene expression involved in the action of antidepressant drugs on memory have not been identified, in this study we investigated the impact of chronic treatment with a SSRI (fluoxetine) and a SNRI (venlafaxine) on the mRNA expression of genes related to memory cascade in the mouse hippocampus, namely, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), nitric oxide synthase 1 (NOS1), neurotrophic tyrosine kinase receptor type 2 (TrKB), mitogen-activated protein kinases (MAPK/ERK) and serotonin transporter (SERT). Animals treated with fluoxetine 10 mg/Kg/day for 28 days showed a significant decrease in the percentage of time spent in the novel object recognition test (p≤0.005) and induced MAPK1/ERK2 down-regulation (p=0.005). Our results suggest that the effect on cognition could probably be explained by fluoxetine interference in the MAPK/ERK memory pathway. In contrast, chronic treatment with venlafaxine did not reduce MAPK1/ERK2 expression, suggesting that MAPK1/ERK2 down-regulation is not a common effect of all antidepressant drugs. Further studies are needed to examine the effect of chronic fluoxetine treatment on the ERK-CREB system, and to determine whether there is a causal relationship between the disruption of the ERK-CREB system and the effect of this antidepressant on memory performance.

Acute ghrelin administration reverses depressive-like behavior induced by bilateral olfactory bulbectomy in mice

This study aims to examine the antidepressant-like action of Ghrelin (Ghr), a hormone synthesized predominantly by gastrointestinal endocrine cells and released during periods of negative energy balance, in two behavioral models: tail suspension test (TST), a predictive model of antidepressant activity, and the olfactory bulbectomy (OB), an established animal model of depression. The reduction in the immobility time in the TST was the parameter used to assess antidepressant-like effect of Ghr. The depressive-like behavior in olfactory bulbectomized mice was inferred through the increase in the immobility time in the TST and the hyperlocomotor activity in the open-field test. Ghr produced antidepressant-like effect in TST (0.3 nmol/μl, i.c.v.), and reversed OB-induced depressive-like behavior. In conclusion, these results provide clear evidence that an acute administration of ghrelin produce antidepressant-like effect in the TST and OB.

Adrenal activity and anxiety-like behavior in fur-chewing chinchillas (Chinchilla lanigera)

Due to its complexity, in combination with a lack of scientific reports, fur-chewing became one of the most challenging behavioral problems common to captive chinchillas. In the last years, the hypothesis that fur-chewing is an abnormal repetitive behavior and that stress plays a role in its development and performance has arisen. Here, we investigated whether a relationship existed between the expression and intensity of fur-chewing behavior, elevated urinary cortisol excretion and anxiety-related behaviors. Specifically, we evaluated the following parameters in behaviorally normal and fur-chewing animals of both sexes: (1) mean concentrations of urinary cortisol metabolites and (2) anxiety-like behavior in an elevated plus-maze test. Urinary cortisol metabolites were higher only in females that expressed the most severe form of the fur-chewing behavior (P≤0.05). Likewise, only fur-chewing females exhibited increased (P≤0.05) anxiety-like behaviors associated with the elevated plus-maze test. Overall, these data provided additional evidence to support the concept that fur-chewing is a manifestation of physiological stress in chinchilla, and that a female sex bias exists in the development of this abnormal behavior.

[Obesity and male fertility]

Obesity and male infertility have increased in the last decades; therefore, a possible association between these pathologies has been explored. Studies inform that obesity may affect fertility through different mechanisms, which alltogether could exert erectile dysfunction and/or sperm quality impairment. These include: 1) hypothalamic-pituitary-testicular (HPG) axis malfunction: obese hormonal profile is characterized by reduction of testosterone, gonadotrophins, SHBG and/or inhibin B concentrations (marker of Sertoli cells function) and hyperestrogenemy (consequence of aromatase overactivity ascribed to adipose tissue increase); 2) increased release of adipose-derived hormones: leptin increase could be responsible for some of the alterations on the HPG axis and could also exert direct deleterious effects on Leydig cells physiology, spermatogenesis and sperm function; 3) proinflammatory adipokines augmentation, higher scrotal temperature (due to fat accumulation in areas surrounding testes) and endocrine disruptors accumulation in adiposites, all of these responsible for the increase in testes oxidative stress and 4) sleep apnea, frequent in obese patients, suppresses the nocturnal testosterone rise needed for normal spermatogenesis. Finally, although controversial, all the above mentioned factors could comprise gametes quality; i.e. decrease sperm density and motility and increase DNA fragmentation, probably disturbing spermatogenesis and/or epididymal function. In summary, although obesity may impair male fertility by some/all of the described mechanisms, the fact is that only a small proportion of obese men are infertile, probably those genetically predisposed or morbidly obese. Nevertheless, it is likely that because the incidence of obesity is growing, the number of men with reduced fertility will increase as well.

Developmental and neurobehavioral effects of perinatal exposure to diets with different omega-6:omega-3 ratios in mice

OBJECTIVE

To investigate in mice the effect of diets enriched with soy or sunflower oil with different omega-6:omega-3 ratios on gestation, reproductive success, physical maturation, and the neurobiological development of the pups.

METHODS

Dams were assigned, throughout gestation and lactation, to different groups: a commercial diet (CD), a soy oil-enriched diet (SOD), or a sunflower oil-enriched diet (SFOD). Measurements during gestation were dams' body weights and daily food intakes. Measurements in the offspring were physical parameters (body weight, body length, body mass index, fur appearance, pinna detachment, incisor eruption, eye opening, and puberty onset) and behavioral preweaning tests (surface righting reflex, negative geotaxis, and cliff avoidance).

RESULTS

The SOD and SFOD dams became significantly heavier than the CD dams from gestational days 14 and 19, respectively, to parturition. There were no significant differences in gestational length or food consumption during pregnancy or lactation or in maternal weight during lactation. Diets did not modify litter size, sex ratio, survival index at weaning, or body weight. The SFOD and SOD offspring were significantly shorter than the CD offspring at weaning. The mean offspring physical scores of SOD and SFOD offspring were higher than CD offspring and simple reflexes were earlier in the SOD and SFOD groups. In SFOD offspring, puberty onset was significantly delayed, at postnatal days 26 and 27 in male and female offspring, respectively.

CONCLUSION

This study suggests that the maintenance of an adequate omega-6:omega-3 ratio is necessary for the optimal growth and development of murine offspring. In populations that do not have sufficient provision of polyunsaturated fatty acids in the diet, their consumption would be advisable during gestation and lactation because these improve most neurodevelopmental outcomes included in this study.

Semen quality and aging: analysis of 9.168 samples in Cordoba. Argentina

OBJECTIVES

Concomitantly with the actual trend towards later fathering, more detailed studies are necessary to establish the relationship between male age and seminal features. The objective of the present paper was to evaluate the relationship of men age with semen quality and with the seminal levels of epididymal and accessory gland markers.

METHODS

The study was conducted as a retrospective study of 9168 cases obtained from the Andrology and Reproduction Laboratory in Cordoba, Argentina for 10 years (1995-2004) (men ages 20 to 77). An important number of factors such as abstinence time, toxic habits, work conditions and drugs consumption has been statistically considered. The parameters measured were: seminal volume, sperm concentration, total sperm count, sperm motility, morphology and viability. Seminal levels of alpha-glucosidase, fructose and citric acid were also evaluated.

RESULTS

We detected a significant decrease in seminal volume, sperm count, motility, viability and normal morphology, and a reduction in alpha-glucosidase and fructose levels in relation to age.

CONCLUSIONS

Since semen quality is a tool for fertility prognosis estimation, the weight of evidence indicates that men may become progressively less fertile as they get older. Couples who decide to delay childbearing should be warned about this matter.

Overweight and seminal quality: a study of 794 patients

OBJECTIVES

To evaluate sperm quality, levels of markers of epididymal and accessory gland function, and T in semen from men grouped according to their body mass index (BMI).

DESIGN

Blind prospective study.

SETTING

Andrology and reproduction laboratory in Cordoba, Argentina (2006-2007).

PATIENT(S)

Seven hundred ninety-four men.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

In semen samples, sperm quality (volume, density, motility, morphology, viability, hypoosmotic swell test, and nuclear maturity) and levels of neutral alpha-glucosidase, fructose, citric acid and T.

RESULT(S)

Multivariate analysis showed a negative association between BMI and motility, rapid motility and neutral alpha-glucosidase levels, and a positive association between BMI and seminal fructose levels. No associations were found among BMI and sperm concentration, the other parameters evaluated, or seminal T levels.

CONCLUSION(S)

Results found in our study support a deleterious effect of obesity on seminal quality, probably by alterations in the function of the epididymis (i.e., in epididymal maturation).

Chronic administration of nonsteroidal-antiinflammatory drugs (NSAIDS): effects upon mouse reproductive functions

Although nonsteroidal-antiinflamatory drugs (NSAIDs) are widely employed, reproductive side effects of prostaglandins long-term inhibition remain unknown. The objective of the present study was to evaluate the effects of chronic low/moderate NSAIDs doses upon mice reproductive functions. Male or female mice were injected (i.p. for 60 or 35 days respectively) with: ibuprofen doses A, B or C (0.56, 1.12 or 1.68 mg/100 g/day respectively) or piroxicam doses A, B or C (0.028, 0.056 or 0.084 mg/100 g/day respectively). Parameters evaluated were: a) in females, spontaneous and induced ovulation, oocyte maturity and spermatozoa migration through genital tract, b) in males, epididymal spermatozoa concentration, motility, viability, resistance to hypoosmotic shock, acrosomal status and membrane maturity and c) in both genders, in vitro and in vivo fertilization, reproductive hormones plasma levels and cyclooxigenase inhibition in reproductive tissues. In females ibuprofen (dose A) elicited a significant reduction in spontaneous and induced ovulation rates and piroxicam (dose A) diminished the concentration of spermatozoa found in the uterus after mating. Males treated with ibuprofen (dose B) showed a reduction in the in vitro fertilization ability. Our data reveal that chronic administration of ibuprofen or piroxicam can exert detrimental effects upon reproductive physiology, which depends on the doses and/or the drug employed.

Time-related changes in functional activity and capacitation of chinchilla (Chinchilla lanigera) spermatozoa during in vitro incubation

The application of assisted breeding programs for chinchilla, an endangered species, requires detailed knowledge about their gamete physiology. Main purposes of the present study were to examine the time-related changes during 8h in vitro incubation in parameters that reflect chinchilla sperm functional activity (including sperm motility, viability, membrane and acrosome integrity), and to determine the incubation time required for achieving in vitro sperm capacitation, evaluated through the quantification of the percentages of sperm that underwent the acrosome reaction in response to progesterone (P, 20 microM) or another acrosome reaction inducer the calcium ionophore, A23187 (20 nM). Semen was obtained by electroejaculation, subjected to swim-up and incubated for 0, 2, 4 and 8h. After these periods, sperm functional activity was assessed. In all treatments percentages of motile, viable and viable sperm with intact acrosomes decreased (p<0.001) after 8h of incubation. The percentages of swollen gametes decreased (p<0.001) after 2h of incubation. Capacitation of chinchilla sperm could be achieved within 4h, as indirectly demonstrated by the increase of acrosome reacted cells in response to P or A23187 (time x treatment interaction: p=0.02).

Neutral α-glucosidase activity in mouse: a marker of epididymal function?

Neutral α-glucosidase (NAG) activity is considered a functional epididymal marker in several species. Unlike the rat, no NAG activity has been detected in mice. The aims of the present study were to evaluate NAG secretory activity (the supernatant of the incubated tissue) in mouse epididymis and to determine whether it could be used as a functional epididymal marker. Epididymides (whole or in parts) were incubated in the presence or absence of testosterone (10−5 m) and secretory NAG activity was compared with known positive controls. Furthermore, we compared enzyme activity in epididymides from well-fed and undernourished mice (50% food restriction for 21 days), a model that alters the epididymal maturation processes. Spectrophotometric analysis revealed NAG activity in mouse epididymis (22.6 ± 3.7 mU g–1 tissue; n = 4), being higher in the caput. NAG activity was statistically higher in the caput than in the corpus and in the cauda. No significant differences existed between the caput NAG activity and complete epididymis NAG activity. In undernourished mice, we confirmed changes in epididymal maturation observed previously (i.e. increased number of immature spermatozoa and diminution of the sperm concentration). Concordantly, the epididymides of undernourished mice exhibited decreased enzyme secretory activity, which increased to values similar to those seen in controls following incubation in the presence of testosterone (22.5 ± 2.6, 12.5 ± 1.0 and 22.4 ± 3.7 mU g–1 tissue, n = 9 in control (n = 7), undernourished (n = 9) and undernourished + testosterone groups (n = 9), respectively). In conclusion, NAG activity was detected in mouse epididymis. Although the present study supports the possibility of using NAG as an epididymal marker, more studies are necessary to effectively prove that NAG activity can be used as an epididymal marker.

Improving the predictive value of the hypoosmotic swelling test in humans

Using a combined hypoosmotic swelling-eosin (HOS-E) technique in human semen samples, we evaluated the frequency of dead swollen spermatozoa (dHOS) after 10 and 30 minutes of incubation, the correlation between total HOS-reactive (tHOS) and viable HOS-reactive (vHOS) spermatozoa with other seminal parameters, and the possibility that dead spermatozoa react to HOS. We obtained the following results: [1] some dead spermatozoa swell under hypoosmotic conditions and [2] HOS-E results correlate strongly with other seminal parameters. We recommend that HOS be performed after 10 minutes of incubation because [1] the increase in the incubation time enhances the percentage of dHOS, [2] there are no differences in vHOS percentages between 10 and 30 minutes, and [3] correlation coefficients between vHOS and tHOS with other parameters are very similar at 10 or 30 minutes of incubation.

Year-round testicular volume and semen quality evaluations in captive Chinchilla lanigera

In mammals, reproductive performance is usually associated with seasons. Chinchilla lanigera, an endemic South American rodent, reproduces throughout the year in captivity but its seasonal breeding pattern is not fully understood. The present study was designed to evaluate (bi-weekly) over 1 year: (1) testicular volume variations and (2) seminal volume, sperm concentration and functional activity changes. Five animals were studied; they were individually housed indoors (22.2 +/- 1.0 degrees C) under natural photoperiod in Argentina (Córdoba, 31 degrees S-64 degrees W). Semen was obtained by electroejaculation; a total of 116 ejaculates was evaluated. Monthly values for paired testicular volume were less in the middle of the summer than in other seasons (p < 0.006), while those for seminal volume and total spermatozoa/ejaculate were not significantly different; these variables ranged between 7.2-30.9 cm(3), 10-130 microL and 0.9-432.6 x 10(6), respectively. Spermatozoa concentration was (x 10(6)/mL) 2145.9 +/- 365.3 and the pH of semen was 7.3 +/- 0.0. Spermatozoa functional activity showed no significant differences between monthly evaluations; confidence intervals were calculated for the means of: motility, 92.2-95.8%; viability, 92.2-96.1%; swollen cells (hypo-osmotic swelling test), 81.2-87.7% and viable intact acrosome, 83.5-89.0%. The present study represents the first longitudinal reproductive assessment in the chinchilla male. In conclusion, males produce spermatozoa continuously that exhibit high quality functional activity.

Assessment of urine and fecal testosterone metabolite excretion in Chinchilla lanigera males

Endemic chinchilla (Chinchilla spp.) populations are nearly extinct in the wild (South America). In captive animals (Chinchilla lanigera and C. brevicaudata), reproduction is characterized by poor fertility and limited by seasonal breeding patterns. Techniques applied for studying male reproductive physiology in these species are often invasive and stressful (i.e. repeated blood sampling for sexual steroids analysis). To evaluate endocrine testicular function, the present experiments were designed to (a) determine the main route of testosterone excretion (14C-testosterone infusion in four males); (b) validate urine and fecal testosterone metabolite measurements (HPLC was used to separate metabolites and immunoreactivity was assessed in all metabolites using a commercial testosterone radioimmunoassay, and parallelism, accuracy and precision tests were conducted to validate the immunoassay); and (c) investigate the biological relevance of the techniques applied (quantification of testosterone metabolite excretion into urine and feces from five males injected with hCG and comparison between 10 males and 10 females). Radiolabelled metabolites of 14C-testosterone were excreted, 84.7+/-4.2 % in urine and 15.2+/-3.9 % in feces. A total of 82.7+/-4.2% of urinary and 45.7+/-13.6% of fecal radioactivity was excreted over the first 24 h period post-infusion (metabolite concentration peaked at 8.2+/-2.5 h and 22.0+/-7.0 h, respectively). Several urinary and fecal androgen metabolites were separated by HPLC but only fecal metabolites were associated with native testosterone; however, there was immunoreactivity in more than one metabolite derived from 14C-testosterone. After hCG administration, an increase in androgen metabolite excretion was observed (p<0.05). Males excreted greater amounts daily of urinary androgen metabolites as compared with females (p<0.05); this difference was not evident in feces. Results of the present study indicate that the procedure used is a reliable and non-invasive method to repeatedly monitor variations in testicular endocrine activity in this species. It can be a useful tool that would help ensure the survival of the wild populations as well as to provide the basis for a more efficient use by the fur industry.

The Effect of Alcohol, Tobacco, and Aspirin Consumption on Seminal Quality among Healthy Young Men

In this study, the authors examined the effects of alcohol, tobacco, and drug use on plasma testosterone and seminal parameters (in accordance with the World Health Organization's standards) in healthy Argentine medical students (n = 34). Some alterations in seminal parameters were detected in 19 (56%) subjects. Alcohol and tobacco use were correlated significantly, p = 0.005; subjects who used these substances exhibited a nonsignificant reduction in sperm concentration, motility, viability, and normal morphology. There was a significant decrease in sperm motility among students who used moderate amounts of aspirin (i.e., > or = 500 mg/wk). The authors concluded that alcohol, tobacco, and aspirin use could have had detrimental effects on seminal parameters and that men who wish to procreate should be warned of such effects. Doses, exposure time, and interactions with other variables deserve additional study.

Effects of alcohol and cigarette consumption on human seminal quality

OBJECTIVE

To evaluate the effects of alcohol or cigarette consumption on seminal parameters in a large population of men attending an andrology laboratory.

DESIGN

Analysis of ten years of data (1990-1999).

SETTING

Andrology and Reproduction Laboratory (Córdoba, Argentina).

PATIENT(S)

Patients (3,976) were grouped according to nonsmokers; <==20 cigarettes/day; >20 cigarettes/day; nonalcohol consumers; <==500 mL of wine ( approximately 52 g of ethanol) or equivalent/day; and >500 mL of wine or equivalent/day. Patients who drank alcohol and smoked were also considered.

INTERVENTION(S)

A questionnaire was voluntarily filled out by patients. It provided data on drug consumption and genitourinary diseases.

MAIN OUTCOME MEASURE(S)

Seminal volume, sperm concentration, motility, viability, and morphology.

RESULTS

No statistical differences in seminal parameters were found between the degrees of alcohol or tobacco consumption; so, independently of the degree of consumption patients were considered as smokers or alcohol consumers.

CONCLUSION(S)

Alcohol or cigarette consumption did not alter the seminal parameters. Nevertheless, when the patients with these two habits were compared to those without these habits, a significant reduction in seminal volume, sperm concentration, percentage of motile spermatozoa, and a significant increase of the nonmotile viable gametes were detected. The synergic or additive effect of these two toxic habits is discussed.

Effects of PDC-109 on bovine sperm functional activity in presence or absence of heparin

PDC-109, a heparin-binding protein (from the seminal vesicles) that binds to sperm surface phospholipids at ejaculation, may modulate several aspects of sperm activity. The objectives of the present study were to determine: (1) in the presence or absence of heparin, the effects of exogenous PDC-109 on sperm motility (Makler chamber), viability (Hoechst 33258) and membrane functional integrity (hypoosmotic swelling test) of bovine spermatozoa; (2) the role of PDC-109 as a capacitation-inducing factor; and (3) its ability to induce the acrosome reaction (fluorescein staining). After 4-h capacitation in the presence of heparin, the addition of PDC-109 (0.5, 1.5 or 3.0mg/ml) significantly decreased the percentages of motile, progressive, and viable cells; these effects were also detected in the absence of heparin. However, PDC-109 elicited a twofold increase (from 14 to 28%) in the proportion of acrosome-reacted spermatozoa, but only in the presence of heparin. Progesterone (10 microM) or angiotensin II (100 or 1000 nM) stimulated the acrosome reaction after capacitation in the presence of PDC-109 without heparin (from 10 to 17, 23 and 22%, respectively). In conclusion, PDC-109 appears to modulate sperm functional activity, with some effects manifest in the absence of heparin.

A non-invasive method for assessing adrenal activity in the chinchilla (chinchilla lanigera)

The Chinchilla is a rodent that was once abundant in the central Andes of South America. Excessive hunting for fur greatly reduced its distribution at the beginning of the twentieth century, and today Chinchilla species are nearly extinct in the wild. Although protected, wild populations of chinchilla are still declining. In general, this species has received little research attention and its biology is poorly understood. Improvements in captive breeding, husbandry, and genetic management are needed to ensure the conservation of the species. In this study, a noninvasive corticosteroid hormone monitoring technique was validated for use in Chinchilla lanigera. Two male domestic chinchillas were administered 3H-corticosterone (i.m.) to determine the time course and relative proportion of urinary and fecal steroid metabolites. Most radioactivity was detected in urine and feces 5-10 and approximately 30 h post-isotope administration, respectively. Corticosteroid immunoreactivity was assessed by corticosterone radioimmunoassay (RIA) and cortisol enzyme immunoassay (EIA). High-pressure liquid chromatography (HPLC) separation of corticosteroid metabolites in unprocessed urine revealed the presence of highly polar corticosteroid metabolites, but after enzymatic hydrolysis and diethyl ether extraction, most immunoreactivity co-eluted with unconjugated cortisol. A 'cause-and-effect' relationship between the administration of exogenous adrenocorticotrophic hormone (ACTH), and the appearance of increased urinary corticosteroid metabolites demonstrated the physiological relevance of these measures for evaluating adrenal status in male chinchillas. From a conservation perspective, these methods can aid in situ and ex situ initiatives designed to evaluate how environmental conditions and management strategies affect overall animal health, well-being and reproduction.