THE EFFECT OF A SINGLE NEONATAL SEX HORMONE INJECTION ON THE GROWTH OF THE RAT PELVIS

1974 ◽  
Vol 77 (3) ◽  
pp. 612-624 ◽  
Author(s):  
P. C. R. Hughes ◽  
J. M. Tanner
Keyword(s):  
Sex Differences ◽  
Testosterone Propionate ◽  
Sex Hormone ◽  
Male Rats ◽  
Hormone Injection ◽  
Males And Females ◽  
Normal Males ◽  
Pelvic Size

ABSTRACT On the 26th day post-copulation (p. c.) male rats were injected with 100 μg Hexoestrol® and females were injected with 1.25 mg testosterone propionate. The growth of the pelvis of these animals was then measured from radiographs taken longitudinally from 23 days p. c. until 140 days p.c. Generally the effect of neonatal sex hormone injection was to diminish, but not abolish, the sex differences in pelvic size. The magnitude of the effect differed according to measurement and sex. Thus ilium length was diminished more in males than it was augmented in females, while ischial length and bi-acetabular width were only slightly diminished in males but considerably increased in females. The effects were greatest in bi-iliac width where both treated groups came to be exactly intermediate between normal males and females.

GONADOTROPHIN PATTERNS IN MALE AND FEMALE RATS:

1968 ◽  
Vol 58 (4) ◽  
pp. 600-612 ◽  
Author(s):  
Robert Boyd ◽  
Donald C. Johnson
Keyword(s):  
Ascorbic Acid ◽  
Testosterone Propionate ◽  
Female Rats ◽  
Female Rat ◽  
Feedback Effects ◽  
Male And Female ◽  
Prostate Weight ◽  
Male And Female Rats ◽  
Males And Females ◽  
Normal Males

ABSTRACT The effects of various doses of testosterone propionate (TP) upon the release of luteinizing hormone (LH or ICSH) from the hypophysis of a gonadectomized male or female rat were compared. Prostate weight in hypophysectomized male parabiotic partners was used to evaluate the quantity of circulating LH. Hypophyseal LH was measured by the ovarian ascorbic acid depletion method. Males castrated when 45 days old secreted significantly more LH and had three times the amount of pituitary LH as ovariectomized females. Administration of 25 μg TP daily reduced the amount of LH in the plasma, and increased the amount in the pituitary gland, in both sexes. Treatment with 50 μg caused a further reduction in plasma LH in males, but not in females, while pituitary levels in both were equal to that of their respective controls. LH fell to the same low level in partners of males or females receiving 100 μg TP. When gonadectomized at 39 days, males and females had the same amount of plasma LH, but males had more stored hormone. Pituitary levels were unchanged from controls following treatment with 12.5, 25 or 50 μg TP daily, but plasma values dropped an equal amount in both sexes with the latter two doses. Androgenized males or females, gonadectomized when 39 days old, were very sensitive to the effects of TP and plasma LH was significantly reduced with 12.5 μg daily. Pituitary LH in androgenized males was higher than that of normal males but was reduced to normal by small amounts of TP. The amount of stored LH in androgenized females was not different from that of normal females and it was unchanged by any dose of TP tested. Results are consistent with the conclusion that the male hypothalamic-hypophyseal axis is at least as sensitive as the female axis to the negative feedback effects of TP. Androgenization increases the sensitivity to TP in both males and females.

scholarly journals Risk-based Decision Making in Rats: Modulation by Sex and Amphetamine

2020 ◽  
Author(s):  
Dannia Islas-Preciado ◽  
Steven R. Wainwright ◽  
Julia Sniegocki ◽  
Stephane E. Lieblich ◽  
Shunya Yagi ◽  
...  
Keyword(s):  
Decision Making ◽  
Sex Differences ◽  
Gonadal Hormones ◽  
Risky Choice ◽  
Female Rats ◽  
Male Rats ◽  
Risky Decision Making ◽  
Risky Decision ◽  
17Β Estradiol ◽  
Males And Females

AbstractDecision-making is a complex process essential to daily adaptation in many species. Risk is an inherent aspect of decision-making and it is influenced by gonadal hormones. Testosterone and 17β-estradiol may modulate decision making and impact the mesocorticolimbic dopamine pathway. Here, we explored sex differences, the effect of gonadal hormones and the dopamine agonist amphetamine on risk-based decision making. Intact or gonadectomised (GDX) male and female rats underwent to a probabilistic discounting task. High and low doses of testosterone propionate (1.0 or 0.2 mg) and 17β-estradiol benzoate (0.3 μg) were administered to assess acute effects on risk-based decision making. After 3-days of washout period, intact and GDX rats received high or low (0.5 or 0.125 mg/kg) doses of amphetamine and re-tested in the probabilistic discounting task. Under baseline conditions, males made more risky choices during probability discounting compared to female rats, particularly in the lower probability blocks, but GDX did not influence risky choice. The high, but not the low dose, of testosterone modestly reduced risky decision making in GDX male rats. Conversely, 17β-estradiol had no significant effect on risky choice regardless of GDX status in either sex. Lastly, a higher dose of amphetamine increased risky decision making in both intact males and females, but had no effect in GDX rats. These findings demonstrated sex differences in risk-based decision making, with males showing a stronger bias towards larger, uncertain rewards. GDX status influenced the effects of amphetamine, suggesting different dopaminergic regulation in risk-based choices among males and females.

The effect of sex and sex hormones on the infection of rats by Trichinella spiralis

1972 ◽  
Vol 50 (5) ◽  
pp. 597-602 ◽  
Author(s):  
Sarojam K. Mankau ◽  
Raymond Hamilton
Keyword(s):  
Sex Hormones ◽  
Worm Burden ◽  
Testosterone Propionate ◽  
Marked Decrease ◽  
Trichinella Spiralis ◽  
Male Rats ◽  
Normal Male ◽  
Normal Males

Male hooded rats infected with Trichinella spiralis larvae had three times more larvae in the muscles than females. Gonadectomized males injected with stilbestrol had a lower worm burden than normal males. Gonadectomized females injected with testosterone propionate harbored far more worms than normal females. Stilbestrol administered to normal male rats caused a marked decrease in T. spiralis, while testosterone administered to normal females resulted in a significant increase in the number of parasites.

Concentrations of immunoreactive tonin in submandibular glands and saliva of the rat

1986 ◽  
Vol 111 (1) ◽  
pp. 140-144
Author(s):  
Yukio Hirata ◽  
Masahiro Tomita ◽  
Takuo Fujita ◽  
Masao Ikeda
Keyword(s):  
Serine Proteases ◽  
Biological Significance ◽  
Male Rats ◽  
Male Rat ◽  
Female Rat ◽  
Adult Males ◽  
Angiotensin I ◽  
Adult Male Rat ◽  
Males And Females ◽  
Normal Males

Abstract. The submandibular gland (SMG) of the rat contains tonin, an enzyme of serine proteases, which specifically cleaves angiotensinogen and angiotensin I to yield angiotensin II directly. Using a specific RIA for rat tonin, the present study was performed to examine the concentrations of immunoreactive (IR) tonin in SMG of normal Wistar male rats with various ages, those in SMG and saliva of normal adult males and females, and also its SMG levels of castrated males and testosterone-treated females. The concentrations of IR-tonin in SMG of immature 4 week old male rats were very low but rose exponentially with increasing age to reach adult levels (3–6 μg/mg wet tissue) in male rats after 6 week old or more. SMG of the adult male rat contained 10-fold more IR-tonin than that of the female rat and male saliva contained 5-fold more IR-tonin than that of females. The concentrations of SMG IR-tonin in the castrated males fell to about one-tenth the levels of normal males, whereas SMG IR-tonin levels in the testosterone-treated females increased about ten times more than those of normal females. These data confirm the sexual dimorphism of rat SMG with respect to the concentrations of tonin and indicate that androgens play an important role in regulating the synthesis and/or storage of tonin in rat SMG. It is also suggested that tonin is secreted into saliva in concentrations reflecting its SMG levels. However, biological significance of tonin in SMG and saliva remains obscure.

scholarly journals Sex Differences and Similarities in Hippocampal Cellular Proliferation and the Number of Immature Neurons during Adolescence in Rats

2019 ◽  
Vol 41 (1-2) ◽  
pp. 132-138 ◽  
Author(s):  
Alina Siddiqui ◽  
Russell D. Romeo
Keyword(s):  
Sex Differences ◽  
Dentate Gyrus ◽  
Cellular Proliferation ◽  
Female Rats ◽  
Male Rats ◽  
Ki 67 ◽  
Cross Sectional ◽  
Male And Female Rats ◽  
Immature Neurons ◽  
Males And Females

Adolescence is associated with significant reductions in hippocampal cellular proliferation and neurogenesis, the physiological and behavioral implications of which are unclear. Though sex differences exist in these proliferative processes in adulthood, relatively little is known about the role sex plays in these adolescent-related changes. To address this gap, we examined cross-sectional area of the dentate gyrus and cellular proliferation, as measured by Ki-67 immunohistochemistry, in pre- (30 days), mid- (45 days), and post-adolescent (70 days) male and female rats. We also investigated the number of immature neurons using doublecortin (DCX) immunohistochemistry in pre- and post-adolescent males and females. Despite increases in the size of the dentate gyrus during adolescence, we found significant adolescent-related decreases in hippocampal proliferation in both males and females, with a more dramatic decrease in males, indicating both age- and sex-dependent changes in the dentate gyrus. We also found an adolescent-related decline in the number of immature neurons in the dentate gyrus of male rats and a female-biased sex difference in the number of immature neurons in adults. Given these significant changes in the dentate gyrus, these data suggest that this period in development might be particularly sensitive to internal and external factors known to modulate neurogenesis, with potential sex-specific neurobehavioral ramifications.

Sex Differences in Cue-Dependency as a Function of Socialization Environment

1967 ◽  
Vol 24 (2) ◽  
pp. 599-602 ◽  
Author(s):  
Richard C. Sherman ◽  
Frances Smith
Keyword(s):  
Sex Differences ◽  
Sex Identification ◽  
Normal Families ◽  
Geometrical Concept ◽  
Males And Females ◽  
Normal Males ◽  
The Given ◽  
Socialization Environment

A formulation by Lynn (1962) proposing that sex differences in cue-dependency are due to differential sex-identification modes was tested. Nineteen Ss from normal families and 20 Ss from a parochial orphanage learned a geometrical concept and then were tested for tendencies to deviate from the given perceptual standard in judging new figures as similar to the learned concept. Differences between normal males and females replicated earlier findings (Wallach & Caron, 1959) in that females were more cue-dependent than males. Differences between orphaned males and females, however, showed a reversed trend. These results were interpreted as supportive of Lynn's formulation.

scholarly journals Sex steroids skew ACE2 expression in human airway: a contributing factor to sex differences in COVID-19?

2020 ◽  
Vol 319 (5) ◽  
pp. L843-L847
Author(s):  
Rama Satyanarayana Raju Kalidhindi ◽  
Niyati A. Borkar ◽  
Nilesh Sudhakar Ambhore ◽  
Christina M. Pabelick ◽  
Y. S. Prakash ◽  
...  
Keyword(s):  
Sex Differences ◽  
Sex Steroids ◽  
Confocal Imaging ◽  
Cell Entry ◽  
Human Airway Smooth Muscle ◽  
Angiotensin Converting Enzyme 2 ◽  
Human Airway ◽  
A Cell ◽  
Males And Females ◽  
Normal Males

The incidence, severity, and mortality of ongoing coronavirus infectious disease 19 (COVID-19) is greater in men compared with women, but the underlying factors contributing to this sex difference are still being explored. In the current study, using primary isolated human airway smooth muscle (ASM) cells from normal males versus females as a model, we explored the effect of estrogen versus testosterone in modulating the expression of angiotensin converting enzyme 2 (ACE2), a cell entry point for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Using confocal imaging, we found that ACE2 is expressed in human ASM. Furthermore, Western analysis of ASM cell lysates showed significantly lower ACE2 expression in females compared with males at baseline. In addition, ASM cells exposed to estrogen and testosterone for 24 h showed that testosterone significantly upregulates ACE2 expression in both males and females, whereas estrogen downregulates ACE2, albeit not significant compared with vehicle. These intrinsic and sex steroids induced differences may help explain sex differences in COVID-19.

SEX DIFFERENCES AND HORMONAL CONTROL OF TESTOSTERONE METABOLISM IN RAT PITUITARY AND BRAIN

1973 ◽  
Vol 59 (3) ◽  
pp. 605-621 ◽  
Author(s):  
CARL DENEF ◽  
CAREW MAGNUS ◽  
B. S. McEWEN
Keyword(s):  
Sex Differences ◽  
Sex Difference ◽  
Testosterone Propionate ◽  
Brain Regions ◽  
Hormonal Control ◽  
Female Rats ◽  
Male Rats ◽  
Testosterone Metabolism ◽  
Conversion Rates ◽  
Oestradiol Benzoate

SUMMARY The in-vitro conversion of testosterone to 17β-hydroxy-5α-androstan-3-one (5α-dihydrotestosterone, DHT) and 3α, 17β-dihydroxy-5α-androstane (3α-androstanediol, DIOL) in pituitary and slices of brain regions was compared between male and female rats. Intact pituitaries from male rats formed 2·5 times more DHT and 1·5 times more DIOL than those of females. A small sex difference was also detected in the hypothalamus, males again being higher than females. No sex differences could be detected in other brain regions. However, DHT formation in the brain was regionally differentiated with higher conversion rates in hypothalamus than in cortex, hippocampus, amygdala, pineal gland or cerebellum. The highest transformation, however, was found in the mid-brain. Metabolism in the pre-optic area was as low as that in the cortex. 5α-Dihydrotestosterone and DIOL formation in the pituitary increased several-fold after gonadectomy in both sexes and the sex difference disappeared. Little or no increase occurred after thyroidectomy or adrenalectomy. The increase in pituitary DHT formation after gonadectomy could be attenuated or prevented both by treatment with testosterone propionate and with oestradiol benzoate. Replacement therapy, particularly with oestradiol benzoate, gave rise to a sex difference reminiscent of that of normal animals. No significant change in pituitary DHT formation occurred in adult females which had been treated with testosterone propionate on the 4th day of life. The results suggested a close relationship between DHT formation and activity of gonadotrophin secretion, particularly at the level of the pituitary.

Lethal mutations in Euphydryas aurinea beckeri (Lederer, 1853) (Lepidoptera: Nymphalidae) from Sierra Blanca, Malaga, Spain

2019 ◽  
Vol 70 (4) ◽  
pp. 211-216
Author(s):  
Jim Pateman ◽  
Peter Russell
Keyword(s):  
The Other ◽  
Lethal Mutations ◽  
Males And Females ◽  
Normal Males

Two Euphydryas aurinea beckeri females from Sierra Blanca, Malaga, Spain were captured and returned to the U.K.; each laid a single egg batch on Succisa pratensis. Both batches hatched and the resulting larvae were reared through to adulthood. One group of larvae produced butterflies with three different mutations: pupae with spines, legs lacking distal tarsals and claws, and with appendages attached to the genitalia which protruded though the rear of the abdomens in both males and females. The other group of larvae produced normal males and females.

scholarly journals Sex Difference in Self-Reported Sexual Functioning Among Frail Older Adults

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 313-313
Author(s):  
Brianne Olivieri-Mui ◽  
Sandra Shi ◽  
Ellen McCarthy ◽  
Dae Kim
Keyword(s):  
Older Adults ◽  
Logistic Regression ◽  
Sex Differences ◽  
Sexual Function ◽  
Older Adult ◽  
Sexual Functioning ◽  
Social Life ◽  
Well Being ◽  
Adult Males ◽  
Males And Females

Abstract Frailty may differentially impact how older adult males and females perceive sexual functioning, an important part of well-being. We assessed the level of frailty (robust, pre-frail, frail) for anyone with data on 11 sexual functioning questions asked in wave 2 of the National Social Life, Health, and Aging Project, 2010-2011 (n=2060). Questions covered five domains: overall sexual function (OSF), sexual function anxiety (SFA), changes in sexual function (CSF), erectile/vaginal dysfunction (EVD), and masturbation. Logistic regression identified sex differences in frailty and reporting worse sexual functioning. Linear regression predicted the number of domains reported as worse. Among males (n=1057), pre-frailty meant higher odds of reporting SFA (OR 1.8 95%CI 1.2-6.6), CSF (OR 1.7 95%CI 1.1-2.7), and EVD (OR 1.5 95%CI 1.0-2.2). Among females (n=1003), there was no difference in reporting by frailty. Females were more likely to report worse OSF (Robust: OR 7.4, 95%CI 4.8-11.4; Pre-frail: OR 6.2, 95%CI 3.9-9.9; Frail: OR 3.4 95%CI 1.7-6.6), but less likely to report SFA (Robust OR .3, 95%CI .2-.5; Pre-frail OR .2, 95%CI .1-.3; Frail OR .2 95%CI .1-.3). Pre-frail and frail females reported fewer domains as worse (Pre-frail coefficient -0.21 SE 0.09, Frail -0.43 SE 0.14). As frailty worsened, males reported more domains as worse (Pre-frail 0.24 SE 0.07, Frail 0.29 SE 0.08). Self-reported sexual functioning differs by sex at all levels of frailty, and reporting by males, but not females, changes with frailty. Providers should be aware that sexual functioning is of importance to both sexes despite varying degrees of frailty.

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