Higher Plasma Testosterone Research Articles

Physiological responses of male goats as affected by genotype and hemicastration

This study was undertaken to evaluate the effect of hemicastration and bilateral castration at one month of age of buck kids representing three genotypes, namely, Egyptian local Baladi (BAL), 1 2 Anglo-Nubian 1 2 Baladi ( 1 2 ANG 1 2 BAL) and 1 2 Alpine 1 1 2 Baladi ( 1 2 ALP 1 2 BAL). Hemicastrated buck kids had significantly higher body weight ( P < 0.01) and daily gain ( P < 0.05) at 12 months of age as compared to those of intact or bilaterally castrated kids. Although, Baladi kids had significantly lower body weight ( P < 0.01) at younger ages (1–6 months) compared to crossbreds, they had higher ( P < 0.01) daily gain at 12 months of age leading to insignificant differences in body weight and higher ( P < 0.01) relative body weight at 12 months of age compared with crossbred buck kids. Hemicastration of male goats at one month of age resulted in ( P < 0.01) hypertrophy and enlargement of the remaining testis and consequently nonsignificant differences in testis circumference and higher values for testis mass index compared to the intact kids. Genotype of kids did not affect any of the testis measurements, however, crossbred males of 1 2 ANG 1 2 BAL had higher values especially testis weight compared to the other genotypes. Blood packed cell volume and haemoglobin contents were not significantly affected by castration treatments. However at 12 months of age both parameters were affected ( P < 0.01) by genotype and were higher in crossbred kids. Hemicastrated kids had higher plasma testosterone ( P < 0.01) that was associated with an increase of plasma total protein ( P < 0,01) and plasma cholesterol ( P < 0.01) concentrations at 9 and 12 months of age compared to intact kids. Hemicastrated kids reached puberty earlier than intact kids as indicated by testosterone concentration and live body weight. In conclusion, hemicastration of male goats at one month of age could be used as a tool to improve animal growth performance without impairing the physiological functions.

The Role of Androgens in Opportunistic Breeding, Tropical Frogs

In this paper we present the results of an interspecific study on the androgen levels of several species of Old World tropical frogs. These data are used to test three hypotheses: (1) in unpredictable, aseasonal environments with opportunistic breeding, gonadal hormones have a permissive rather than an activating role in the expression of mating behavior (Crews and Moore, 1986), (2) a behaviorally induced androgen response is present in opportunistic aseasonal species as well as in temperate seasonal breeders (Crews and Moore, 1986; Wingfieldet al.,1990), and (3) because maintenance of high plasma testosterone levels has an associated energetic and/or fitness cost (Moore and Marler, 1987; Wingfieldet al.,1990), continuously breeding frogs have lower testosterone levels than seasonal, discontinuous breeders. Androgen and corticosterone levels were found to vary significantly among species exhibiting the same mating behavior, providing support for the hypothesis that hormones have a permissive role. Differences in androgen level were correlated with (1) variation in level of male–male aggression, (2) relative density of male frogs, and (3) call rate and power output of male vocalization. These results indicate that a behaviorally induced androgen response is present in opportunistic, aseasonal breeders. Furthermore, tropical, aseasonal, opportunistic breeding frogs appeared to have lower androgen levels, generally, than confamilial temperate, seasonal breeders. This difference is consistent with the hypothesis that maintenance of high plasma testosterone levels is energetically expensive.

Infantile acne associated with a high plasma testosterone level in a 21-month-old boy

and forearms is typical of photodistributed LDE.4 The histopathologic findings in our patient were also consistent with an LDE.5 The previously reported case also showed the typical changes of an LDE, although eosinophils were seen within the dermal infntrate. Although eosinophils were not present in our case, a study by West, Berger, and LeBoit4 comparing histologic features in photodistributed versus nonphotodistributed LDE found eosinophils in only 1 of 8 patients with photodistributed lesions. Similarly, Van den Haute, Antoine, and Lachapelle5 reported that eosinophils were found in only two patients of their series of 15 with LDE.’ Frequently, patients with LDE are taking many drugs, which can make identification of the offending agent difficult6 Our patient had been receiving more than 20 medications, most over months. However, only ethambutol is known to be associated with LDE. The rapid response to its withdrawal supports it as the cause of the eruption. In our patient, the eruption was in a photodistribution as was the previously reported case, which suggests that UV light plays a role in ethambutol-induced LDE.

A new deletion of the 5α‐reductase type 2 gene in a Turkish family with 5α‐reductase deficiency

The molecular basis for male pseudohermaphroditism produced by the 5 alpha-reductase deficiency is becoming increasingly understood. We have performed biochemical and molecular analyses of the 5 alpha-reductase type 2 gene in a Turkish family with a 5 alpha-reductase deficiency. A 46,XY prepubertal Turkish patient with female phenotype showing clitoral hypertrophy, high plasma testosterone and dihydrotestosterone, and normally differentiated and developed testosterone-dependent internal genitalia. 5 alpha-Reductase activity, measured by the conversion of 3H-T into 5 alpha-reduced compounds, was determined from cultured genital skin fibroblasts by both intact monolayer assay and cell-free extracts at various pH values. The five exons of the 5 alpha-reductase type 2 gene were sequenced after enzymatic amplification (PCR) of the patient's genomic DNA. Labelled PCR of the consanguineous parents' DNA was submitted to electrophoresis on a sequencing gel. A marked decrease in the transformation of T into 5 alpha-reduced compounds by intact cells and a diminished 5 alpha-reductase activity at acidic pH by sonicated cell extracts strongly suggested a 5 alpha-reductase type 2 deficiency. Molecular analysis of the 5 alpha-reductase type-2 gene showed a trinucleotide deletion straddling codons 156 and 157, responsible for a methionine residue deletion at position 157 of the protein. The parents' DNA contained both normal and deleted alleles. This is the third deletion described in the 5 alpha-reductase type 2 gene. The deleted methionine 157 is conserved in both types 1 and 2 of human and rat 5 alpha-reductase, which suggests its crucial role in the functioning of the enzyme. This gene rearrangement was thus clearly responsible for the reduced 5 alpha-reductase activity and abnormal genital development in this patient.

Longitudinal patterns of physical aggression: Associations with adult social, psychiatric, and personality functioning and testosterone levels

AbstractA retrospective longitudinal research design was used to evaluate male adult outcomes associated with four patterns of physical aggression from childhood to adulthood—child-only aggression, child and adult continuity of aggression, adult-onset aggression, and a contrast group with low levels of aggression in childhood and adulthood. The continuity and adult-onset aggression groups had the highest levels of social maladjustment (e.g., marital instability), psychiatric disturbance (e.g., alcohol disorders, major depression), personality dysfunction (e.g., higher prevalence of elevated borderline and narcissistic personality disorder scores), and higher plasma testosterone levels. The child-only aggression group manifested more psychiatric and personality disturbance than the contrast group, but not nearly as much disturbance as the continuity and adult-onset groups. After controlling for age and socioeconomic status (SES) variables, race (White/Black) was typically not a significant predictor of outcome variables. Findings are discussed with regard to life course implications of the physical aggression patterns, and of the support provided for an adult-onset aggressive type.

Behavioral and endocrinological correlates of social status in the male sugar glider ( Petaurus breviceps Marsupialia: Petauridae)

Socially dominant male sugar gliders are heavier than socially subordinate males, have higher plasma testosterone and lower cortisol concentrations, win more social encounters, scan the arena more, scent-mark more, and are more active and move more quickly, even though they spend more time in the colony nesting box. When they are transferred into a foreign stable colony there is an impressive reversal of behavioral measures and a concomitant decrease in concentration of plasma testosterone and rise in cortisol that is apparent over the first 3 weeks of observation.

Effects of cyproterone acetate on sexual arousal patterns of pedophiles

The antiandrogen treatment of sexual offenders has been shown to reduce the recidivism rate. The mechanism of action has been assumed to be through asexualization with its secondary effects on sexual behavior. This study shows that the mechanism may be more complex and may involve a differential effect on sexual arousal patterns. Treatment responses may differ in high and low plasma testosterone groups.

Heat-stress response of broiler cockerels to manipulation of the gonadal steroids, testosterone and estradiol

1. 1. Estradiol supplementation resulted in heat-stress mortality in both intact and caponized cockerels accompanied by depressed plasma c corticosterone. 2. 2. Phenotype-selection for large comb and high plasma testosterone increased heat tolerance which was attributed to an increased plasma corticosterone. 3. 3. The results suggested that the presence of testosterone had a positive influence on the heat tolerance of broiler cockerels.

The Texas Experience with DepoProvera

We are reporting on our experience with treatment of sex offending behaviors with anti-androgen therapy (DepoProvera) to control sex offending behaviors. In the last ten years, we have had the opportunity to compare a group of men who received DepoProvera to a group who had the same clinical and legal problems of sexual offenses but who refused pharmacological treatment. Both groups received group therapy, individual therapy, and sometimes family therapy. The goal of treatment was to prevent further victimization, develop personal insight. enhance self esteem, and to make restitution to society through successful probation and parole, working regularly, and meeting their adult responsibilities. Side effects of the medication can be serious and include formation of gall stones, weight gain, malaise, muscle cramps, and even diabetes. Outcome results indicate that possible factors signifying an increased likelihood of re-offense are high initial plasma testosterone, regressed behavior type, exhibitionism, co...

Psychosocial job factors and symptoms from the locomotor system--a multicausal analysis

The effects of physical and psychosocial work environment factors on emotions, psychosomatic and endocrine (cortisol and testosterone) states, back pain, symptoms of degenerative joint disease, and absenteeism for sickness, were studied in 147 men and 60 women in six occupations representing widely different physical and psychological activities. In most subjects, measurements were carried out twice to four times over one year. Statistical analyses were performed of the associations between different factor levels, such as age, gender, height, body mass index, and physical stressors at work. It was found that psychological work demands were associated with physiological indicators of strain (plasma cortisol and self-reported muscle tension) and that self-reported muscle tension was associated with several emotional reactions as well as with symptoms from the back, neck and shoulders. Little possibility for decision-making was associated with a high rate of absenteeism for sickness. In men, a high plasma testosterone level was associated with self-reported muscle tension. The results indicate that work environment factors influence mood, bodily tension and somatic symptoms, but that load on the locomotor system and opportunity to influence decisions play an important and more direct role in absenteeism for sickness.

Reproductive performance and productive traits of beef bulls selected for different levels of testosterone response to GnRH

In two separate studies, one with four Hereford-Shorthorn and one with three Zebu × British crossbred bulls, the efficacy of using the testosterone response to gonadotrophin-releasing hormone (GnRH; Lutal, Hoechst) to predict differences in reproductive performance was assessed. Young bulls (17 or 29 months of age) selected for low to high (3.1 to 10.3 ng/ml) peak plasma testosterone 2 to 2.5 hours after the intramuscular injection of GnRH (62.5 to 2000 ng/kg LWT) were each later individually joined with groups of 19 to 30 cows in which estrus had been synchronized. In both studies, the rankings of bulls for overall fertility (capable cows pregnant), for libido (estrous cows mounted), and for fertilizing ability (mounted cows pregnant) were in close agreement with rankings for testosterone responses to GnRH. In the Bos indicus bulls rankings for both reproductive performance and testosterone response to GnRH were repeatable when measured at two and four years of age. Other reproductive measurements (semen quality, scrotal circumference, pen-type serving capacity tests) were less reliable predictors of reproductive performance. Measurements of liveweight gains and parasite resistance indicated that bulls superior for these characteristics do not always have satisfactory reproductive performance. These studies suggest that the testosterone response to GnRH could be a useful test to ensure that bulls selected for productive traits have adequate reproductive potential.

Demonstration of an odorous intramale primer effect in short-tailed vole,Microtus agrestis L.

Anal (proctodeal) glands of maleMicrotus agrestis housed in social isolation undergo severe atrophy. Their weight and volume is significantly lower than those of the stock control males. The atrophied glands can be revived by subjecting deprived voles to various social odors. Atrophied glands of isolated males do not respond to the odors of male and female urine, voided feces of females, and unvoided feces of males. Atrophied anal glands of males exposed to voided male feces (which have passed the orifice of the anal gland) and soiled bedding from adult males show strong recrudescence. The mean weight and volume of the glands and plasma testosterone level are significantly higher than of males maintained in complete social isolation, although they are significantly less than those of stock control males. Atrophied glands of socially deprived males strongly respond to the odor of ethereal extract of gland secretion. In males exposed daily to anal gland secretion extract, the weight and volume of the gland and plasma testosterone level increase and are not significantly different from those of stock controls. They enjoy higher plasma testosterone levels and consequently larger and more active anal glands than complete isolates.

Dose and time effects of treatment with low doses of a LRH agonist on testicular axis and accessory sex organs in rats.

LRH and its agonists have been shown to exert both stimulatory and inhibitory effects on testicular function. In the present study, the dose and length of treatment were tested to determine the appearance of the stimulatory and inhibitory effects of LRH agonist on testicular axis including the three levels. Two doses of an agonist of LRH, 40 and 100 ng/100 g body weight (buserelin, 'agonist'), were administered daily for 1 to 15 days to adult male rats. Control rats received the vehicle only. On day 1, 2, 4, 8 and 15 of treatment, the pituitary, testicular and peripheral levels (weight of accessory sex organs and androgen receptors in ventral prostate) were tested 6 h after the last injection. For the 15 days of treatment with both doses, a stimulatory effect of the 'agonist' was observed on LH and FSH release. A short exposure (1-2 days) to the low dose of the 'agonist' had a stimulatory effect on the density of LH/hCG testicular receptors (326 +/- 49 vs control 185 +/- 21 fmol/mg protein, mean +/- SEM), on the weights of seminal vesicles and ventral prostate and exposure to both doses led to high plasma testosterone levels (13.8 +/- 0.5 and 13.7 +/- 0.7 ng/ml, respectively, vs control 2.6 +/- 0.3 ng/ml), and to an increased density of nuclear androgen receptors in the ventral prostate (142 +/- 9 and 144 +/- 15 fmol/mg protein respectively vs control 97 +/- 12 fmol/mg protein).(ABSTRACT TRUNCATED AT 250 WORDS)

Possible role of prolactin in the inhibitory effect of testosterone on the hypothalamic-pituitary-testicular axis in the rat.

To study the role of testosterone on the regulation of the hypothalamic-pituitary-testicular axis, young intact male Wistar rats were given acute (24 h) or chronic (5 days) subcutaneous treatments of 500 micrograms testosterone propionate (TP) or vehicle alone. Plasma LH, prolactin and testosterone levels were measured both basally and after administration of LH-releasing hormone (LHRH) or human chorionic gonadotrophin (hCG) by means of specific radioimmunoassay systems using materials supplied by the NIADDK. After acute treatment with TP there was an increase in basal plasma testosterone concentrations and no modification in the hCG response when compared with vehicle-treated animals. No difference could be detected in basal plasma testosterone levels after the chronic treatment, but a significant reduction in the hCG response was observed. Both acute and chronic treatments with TP resulted in a significant decrease of basal plasma LH levels. A reduced LH response to LHRH in acutely treated rats and no response in the chronically treated rats was detected. Plasma prolactin levels showed an increase after both acute and chronic treatments. To evaluate the possible role of the increased plasma prolactin levels on the above modifications during TP treatment, another group of animals was treated with TP and bromocriptine (dopamine agonist) simultaneously to avoid the increase in plasma prolactin levels. In this situation, neither basal plasma LH levels nor the response to LHRH were altered when compared to vehicle-treated rats; a normal testosterone response to hCG stimulation was observed in spite of the high basal plasma testosterone levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma testosterone transport in primates

All primate species, including Old and New World primates and prosimians have a plasma testosterone-estradiol binding globulin (TeBG), which is a glycoprotein and has a similar mobility in polyacrylamide gel electrophoresis. In New World primates the TeBG binding capacity for [ 3H]testosterone was higher and its affinity lower than in Old World primates. These changes were associated with high unbound plasma testosterone concentrations in these species. Binding parameters of TeBG in prosimian species varied markedly. Thus, in primate evolution TeBG was conserved despite marked differences in binding characteristics. In New World primates changes are associated with high total and unbound testosterone, a finding concordant with alterations of other steroid hormones concentration in these species with “generalized steroid hormone resistance”.

Malignant Transformation of Polyostotic Fibrous Dysplasia

We have described an unusual case of polyostotic fibrous dysplasia in a 25-year-old white woman who had malignant transformation into a mesenchymal tumor with widespread metastases and features of rhabdomyosarcoma. Masculinization also occurred with high plasma testosterone levels. A mechanism for the development of masculinizing features is discussed.

Study of testicular activation in early infancy using the newborn lamb as experimental model

Higher plasma testosterone (T), LH and FSH at 5 wks of age in the male lamb found by Lee et al and in this laboratory suggest its usefulness as an experimental model for the study of early postnatal testicular activation in the human. Pulsatile LH release and T secretion were more important at 2 and 8 wks than at 4 wks but hCG increased T secretion similarly. Hemicastration was done in 2, 4 and 8 wk old lambs and saline or hCG (500 IU/kg) administered 2 h prior to removal of the 2nd testis. 17,20 Lyase and 3 HSD were measured. In collaboration with doctors M.G. Forest and J.M. Saez of Lyon, isolated interstitial cells were prepared and hCG binding sites, T and cAMP secretion measured. An 8 to 10 fold increase in plasma T was observed 2 h post hCG. T production by isolated interstitial cells was increased by cAMP, choleratoxin and hCG but in hCG pretreated animals, T response was not further enhanced. Higher in vitro responsiveness was observed at 4 wks. These results suggest a transitory increased reactivity of the pituitary gonadal axis in early life.

Relationship between testicular blood flow, testosterone secretion and spermatogenic activity in young and adult wild red foxes (Vulpes vulpes).

Testicular capillary blood flow (TCBF) was measured by the radioactive inert gas clearance technique throughout the reproductive life of young adult foxes and was related to the spermatogenic and androgenic activities of the testis. Mean (+/-S.E.M.) blood flow (ml min-1 g-1) was maximal in January in adults during the mating period (0-65 +/- 0-03), and in pubertal animals (0-62 +/- 0-04). At this time spermatozoa were observed in the testes of all animals, but testicular weight and circulating testosterone levels were lower in the pubescent foxes than in the adults. TCBF was minimal during immaturity (0-29 +/- 0-03) and during the resting period of the adult (0-12 +/- 0-01). These values were associated with a low testosterone level and with the multiplication of gonocytes in the young or with the seasonal very low spermatogenic activity in the adult. During the prepubertal period, TCBF slowly increased and was accompanied by testicular growth. In the adult, in September, TCBF rapidly increased without changes of testicular size and then slowly increased as the testes enlarged. High plasma testosterone concentrations occurred later. During the period of testicular regression, TCBF, testicular size, spermatogenic and androgenic activities decreased together.

Male Pseudohermaphroditism With Partial Androgen Insensitivity

Androgen insensitivity was demonstrated in two male siblings with partial masculinization of the external genitalia. They had a previously undescribed defect characterized postpubertally by high plasma testosterone and luteinizing hormone concentrations with low serum follicle-stimulating hormone levels. Studies in skin fibroblasts showed normal androgen receptor affinity and capacity for 5alpha-dihydrotestosterone (DHT), normal nuclear retention of the receptor-DHT complex, and normal conversion of testosterone to DHT.

94: Binding capacity of serum Testosterone-Estradiol Binding Globulin (TeBG) in males: Variations with age and pathological conditions

The binding capacity of TeBG was determined by polyacrylamid gel electrophoresis after preincubation of serum with 3H-dihydrotestosterone (3H-DHT). Steady state binding conditions were obtained by initial disolving of 3H-DHT in the gel. In these conditions, the binding of 3H-DHT to TeBG was displaced by addition of unlabel-led DHT. The saturation curve was determined by addition of increasing concentrations of 3H-DHT in serum incubates. At saturation, the TeBG binding capacity of serum (BC) expressed as μg p. cent ml was calculated from the peak of radioactivity. Mean ± SD BC value was 3.85 ± 0.37 in prepubertal boys and significantly lower (p<0.01) in adult men : 1.47 ± 0.6. In boys from birth to 6 months mean BC value was 3.5 ± 1.6, while it was only 1.37 ± 0.3 in cord blood. In 2 boys with precocious puberty BC values were 0.34 and 1.6, and in 3 patients with complete testicular feminisation (TF) 4.41, 4.83 and 5.90. The association of a low BC and a high plasma testosterone level is concomitant of male pubertal development, while the association of a high BC with testosterone level in the adult range, present in TF and male new-borns, seems characteristic of a peripheral inactivity of testosterone.