INFLUENCE OF NEONATAL ANDROGENIZATION ON THE RESPONSE OF α2u-GLOBULIN TO TESTOSTERONE AND DEXAMETHASONE IN THE RAT

The influence of neonatal androgens on the response of α2u-globulin to testosterone propionate or dexamethasone in adult rats has been investigated. It has been demonstrated previously that contact with androgens during the perinatal period results in higher unstimulated levels of α2u-globulin in the serum of adult rats and in higher levels of this protein when the animals are stimulated either with androgens or glucocorticoids. As shown here, however, non-androgenized animals reached comparable serum levels to their neonatally androgenized litter-mates only during prolonged stimulation with testosterone propionate. Previous exposure to androgens during adulthood did not result in comparable differences in levels of α2u-globulin in non-stimulated or stimulated rats. The residual sex difference in the stimulated levels observed in neonatally gonadectomized and oil-treated animals suggested that the sensitive period for this imprinting effect extends into the prenatal period.

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Effect of the anterior pituitary gland and gonads on enzyme components of the hepatic microsomal cytochrome P-450 system of male and female rats

Journal of Endocrinology ◽

10.1677/joe.0.0960259 ◽

1983 ◽

Vol 96 (2) ◽

pp. 259-267 ◽

Cited By ~ 1

Author(s):

B. Gillham ◽

J. S. M. Hutchinson ◽

M. B. Thorn

Keyword(s):

Sex Difference ◽

Anterior Pituitary ◽

Testosterone Propionate ◽

Specific Activity ◽

Female Rats ◽

Intact Male ◽

Adult Rats ◽

Microsomal Cytochrome ◽

Male And Female Rats ◽

Cytochrome P 450

The concentration of cytochrome P-450 in microsomes prepared from the livers of mature female Wistar-derived rats was significantly lower than in mature males. This sex difference was abolished after hypophysectomy, when the concentration of the cytochrome in males and females was not significantly different from that in the intact male. A concentration of cytochrome P-450 characteristic of females was restored by two anterior pituitary transplants under the kidney capsule of hypophysectomized females; a partial 'feminization' occurred in similarly treated hypophysectomized males. A partial 'feminization' was also achieved by the administration of rat or sheep prolactin to hypophysectomized females. Unexpectedly, the administration of l-dihydroxyphenylalanine to normal females was without effect on cytochrome P-450, whereas in intact males 'feminization' resulted. Castration of adult rats resulted in the 'feminization' of cytochrome P-450, whereas ovariectomy was without effect. Administration of testosterone propionate for 10 days, either immediately after the operation or 14 weeks later to rats castrated when adult failed, however, to reverse the fall in cytochrome P-450. The establishment of a higher concentration of cytochrome P-450 in the liver of female rats could not be brought about by the administration of testosterone propionate, whether given as a single dose on the second day after birth or as a 10-day course of treatment after puberty or both. It is concluded that the sex difference in hepatic microsomal cytochrome P-450 is maintained by the release in the female of an anterior pituitary factor(s) that serves to depress its concentration. The factor(s) shows some of the characteristics of prolactin but the findings are not consistent with that hormone being responsible for all of the effects observed. The release of the factor(s) in the male may be inhibited by a compound of gonadal origin other than testosterone. A sex difference could not be 'imprinted' in the female by either neonatal and/or postpubertal testosterone treatment. The concentration of hepatic microsomal cytochrome b5 and the specific activity of NADPH-cytochrome c reductase were found not to be sex-dependent in the rats used. However, anterior pituitary factor(s) other than prolactin and growth hormone act to suppress partially the concentration of the former and to promote the specific activity of the latter in the endoplasmic reticulum of rat hepatocytes.

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CONTROL OF PITUITARY FSH IN MALE RATS

Acta Endocrinologica ◽

10.1530/acta.0.0760235 ◽

1974 ◽

Vol 76 (2) ◽

pp. 235-241 ◽

Cited By ~ 17

Author(s):

Emil Steinberger ◽

Mridula Chowdhury

Keyword(s):

Plasma Levels ◽

Testosterone Propionate ◽

Serum Levels ◽

Male Rats ◽

Time Intervals ◽

Adult Rats ◽

Marked Rise ◽

Slight Elevation

ABSTRACT The pituitary and serum FSH levels were measured in cryptorchid or orchiectomized adult rats at time intervals up to 7 days after surgery utilizing a radioimmunoassay technique. In orchiectomized rats the pituitary levels showed a decline during the first 72 hours after surgery while serum levels showed an increase during this period of time. Between the 3rd and 7th days after surgery the serum levels remained elevated and pituitary levels depressed. In cryptorchid animals the pituitary levels showed marked rise during the first 72 hours after surgery and remained elevated until the end of the experiment. The serum levels showed no change during the first 72 hours and a slight elevation by 7 days. Administration of testosterone propionate (TP) prevented the ochiectomyinduced changes in pituitary and plasma FSH levels. A dose relationship was observed between the serum FSH levels and the dose of TP. With increase in TP dose up to 0.5 mg an increase in pituitary FSH levels was observed. Further increase in TP dose caused a drop in pituitary FSH levels. The plasma levels showed a progressive drop with increasing doses of TP. The data reported in this paper and information available in literature lead the authors to the conclusion that testosterone regulates primarily FSH release rather than its synthesis.

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OVARIAN SENSITIVITY TO OVULATORY STIMULI IN THE ANDROGEN-INDUCED PERSISTENT-OESTROUS RATS

Acta Endocrinologica ◽

10.1530/acta.0.0660266 ◽

1971 ◽

Vol 66 (2) ◽

pp. 266-272

Author(s):

Anant P. Labhsetwar

Keyword(s):

Testosterone Propionate ◽

Ovarian Response ◽

Minimal Amount ◽

Normal Complement ◽

Adult Rats ◽

Induced Ovulation ◽

Postnatal Treatment ◽

Small Doses

ABSTRACT The ovarian response of adult rats made persistent-oestrus by the postnatal treatment with testosterone propionate was examined by determining the number of ova shed in response to small doses of LH and/or FSH, and placental gonadotrophins (PMSG or HCG). A dose of LH (10 μg/rat) estimated to be equivalent to twice the minimal amount secreted for ovulation in normal rats failed to release a normal complement of ova. The same dose of FSH induced ovulation in 40% of rats with an ova count of 5.7 ± 1.8/rat. Both placental gonadotrophins induced ovulation, although the ova yield was significantly below the normal oestrous control. It is inferred from these findings that the ovarian sensitivity of androgen-sterilized rats is far below that of the normal animals despite the presence of numerous follicles in the ovaries of the persistent-oestrous rats.

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Cholestasis Alters miR-34c-5p Expression in the Testes of Male Wistar Rats

Gene Cell and Tissue ◽

10.5812/gct.110807 ◽

2021 ◽

Vol In Press (In Press) ◽

Author(s):

Amir Hossein Hasani Fard ◽

Hanieh Jalali ◽

Homa Mohseni Kouchesfehani

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Target Genes ◽

Serum Levels ◽

Testicular Tissue ◽

Adult Rats ◽

Altered Expression ◽

Rat Models ◽

Duct Ligation ◽

Male Wistar Rats

Background: Cholestasis is a pathophysiological condition, significantly reducing spermatozoa production. MiR-34c is highly expressed in adult male testicles and controls different stages of spermatogenesis. Objectives: Here, we aimed to investigate miR-34c expression in the testes of rat models of cholestasis. The expressions of THY-1, FGF-2, and CASP-3 genes, that are targeted by mirR-34c were also investigated. Methods: Cholestasis was induced in six adult rats via bile duct ligation. Four weeks after cholestasis induction, sera and testicular tissues were collected for further examinations. The levels of liver enzymes were measured using the ELISA. The structure of the testes was evaluated by histological examination. Total RNA was extracted from testes using a special kit and converted to cDNA. The expressions of miR-34c-5p, THY-1, FGF-2, and CASP-3 genes were determined by Real-Time PCR. Results: The serum levels of ALP, AST, and ALT were significantly elevated in the rat models of cholestasis (P < 0.001). Real-Time PCR revealed that the expressions of miR-34c-5p, THY-1, and FGF-2 genes decreased while CASP-3 gene was upregulated in the testes of cholestatic animals (all differences were significant at P < 0.05). Conclusions: Our study indicated that cholestasis was associated with reduced expression of miR-34c and altered expression of its target genes in the testis. Our results highlight the potential effects of cholestasis, a hepatobiliary disease, on testicular tissue function and male fertility.

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Short-term regular moderate exercise improved male hypothalamic-pituitary-gonadal axis function via the reduction of hypothalamic neurokinin B expression in adult rats

Physiology and Pharmacology ◽

10.32598/ppj.25.2.20 ◽

2021 ◽

Vol 25 (2) ◽

pp. 171-177

Author(s):

Nazli Khajehnasiri ◽

◽

Homayoun Khazali ◽

Farzam Sheikhzadeh Hesari, ◽

Hamid Reza Sadeghnia ◽

...

Keyword(s):

Molecular Mechanisms ◽

Serum Levels ◽

Moderate Exercise ◽

Short Term ◽

Neurokinin B ◽

Adult Rats ◽

Hpg Axis ◽

Intensive Exercise ◽

Reproductive Axis ◽

Gnrh Neurons

Introduction: In the arcuate nucleus, kisspeptin, neurokinin-B and pro-dynorphin (KNDy) neurons control the function of gonadotropin-releasing hormone (GnRH) neurons. Early investigations indicated that exercise with various intensities affects luteinizing hormone (LH) and testosterone (T) in different ways. Meanwhile the molecular mechanisms underlying its function not yet been fully understood. Accordingly, the present study evaluated the role of alterations in the levels of KNDy mRNA upstream of GnRH neurons in conveying the effects of various short-term exercise intensities on the male hypothermic-pituitary-gonadal (HPG) axis. Methods: Twenty-one adult Wistar rats were randomly divided into 3 groups: control, one-month regular moderate exercise (ME) and one-month regular intensive exercise (IE). In ME (22m/min) and IE (35m/min) groups, the rats were treated 5 days a week for 60min each day. Finally, we assessed serum levels of LH and T using the ELIZA technique and KNDy and Gnrh mRNA expression by the real-time PCR method. Results: The results revealed that in ME group the expression of Nkb was reduced and the expression of Gnrh mRNA and the LH and T serum levels were increased. However, intensive exercise did not change the serum levels of LH and T or the relative expression of kiss1, Nkb, Pdyn and Gnrh genes. Conclusion: The results suggested that monthly moderate exercise improved male reproductive axis function, while intensive exercise did not have an adverse effect on the reproductive axis. These various effects on the male HPG axis may be propagated by the change in hypothalamic Nkb gene expression.

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FACTORS INFLUENCING THE EXCRETION OF A FAT-MOBILIZING SUBSTANCE IN THE URINE OF RATS

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y66-011 ◽

1966 ◽

Vol 44 (1) ◽

pp. 95-101 ◽

Cited By ~ 3

Author(s):

J. R. Beaton ◽

A. J. Szlavko ◽

J. A. F. Stevenson

Keyword(s):

Body Weight ◽

Sex Difference ◽

Specific Activity ◽

Young Male ◽

Total Activity ◽

Female Rats ◽

Male Rats ◽

Diabetic Rat ◽

Adult Rats ◽

Factors Influencing

The effect of various factors on excretion of a lipid-mobilizing activity in FMS IA (anorexigenic) and in FMS IB (fat-mobilizing) by the fasting rat has been investigated. During fasting, the greatest excretion of such activity in FMS IA and FMS IB occurred in the first 24 hours and diminished thereafter up to 72 hours; and the specific activity of FMS IB was greatest in the first 24 hours whereas that of FMS IA was constant throughout. The hypothalamicobese rat excretes FMS IA and FMS IB in greater than normal amounts. The alloxan-diabetic rat excretes less total activity of FMS IA and IB than do control animals. Young male rats excrete greater amounts of FMS IB, but not of FMS IA, than do adult rats, the greatest excretion per 100 g body weight being observed at approximately 37 days of age. At 27 days of age (prepuberty), male rats excreted a greater total activity of FMS IB but not of FMS IA than did female rats. At 90 days of age (post-puberty), there was no apparent sex difference in the amount of total activity of FMS IB excreted per rat, but when expressed per 100 g body weight, females excreted more FMS IB than did males.

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Gender-related long-term effects in adult rats by perinatal dietary ratio of n-6/n-3 fatty acids

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00342.2004 ◽

2005 ◽

Vol 288 (3) ◽

pp. R575-R579 ◽

Cited By ~ 70

Author(s):

Marina Korotkova ◽

Britt G. Gabrielsson ◽

Agneta Holmäng ◽

Britt-Marie Larsson ◽

Lars Å. Hanson ◽

...

Keyword(s):

Fatty Acids ◽

Linseed Oil ◽

Maternal Diet ◽

Perinatal Period ◽

Late Gestation ◽

Male Rats ◽

Long Term Effects ◽

Adult Rats ◽

Serum Leptin

Epidemiological studies in humans have shown that perinatal nutrition affects health later in life. We have previously shown that the ratio of n-6 to n-3 polyunsaturated fatty acids (PUFA) in the maternal diet affects serum leptin levels and growth of the suckling pups. The aim of the present study was to investigate the long-term effects of various ratios of the dietary n-6 and n-3 PUFA during the perinatal period on serum leptin, insulin, and triacylglycerol, as well as body growth in the adult offspring. During late gestation and throughout lactation, rats were fed an isocaloric diet containing 7 wt% fat, either as linseed oil (n-3 diet), soybean oil (n-6/n-3 diet), or sunflower oil (n-6 diet). At 3 wk of age, the n-6/n-3 PUFA ratios in the serum phospholipids of the offspring were 2.5, 8.3, and 17.5, respectively. After weaning, all pups were given a standard chow. At the 28th postnatal wk, mean body weight and fasting insulin levels were significantly increased in the rats fed the n-6/n-3 diet perinatally compared with the other groups. The systolic blood pressure and serum triacylglycerol levels were only increased in adult male rats of the same group. These data suggest that the balance between n-6 and n-3 PUFA during perinatal development affects several metabolic parameters in adulthood, especially in the male animals.

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EFFECTS OF TESTOSTERONE MEDIATED OR MODULATED BY PITUITARY FACTORS

Journal of Endocrinology ◽

10.1677/joe.0.0670071 ◽

1975 ◽

Vol 67 (1) ◽

pp. 71-79 ◽

Cited By ~ 8

Author(s):

P. DE MOOR ◽

M. ADAM-HEYLEN ◽

H. VAN BAELEN ◽

G. VERHOEVEN

Keyword(s):

Body Weight ◽

Testosterone Propionate ◽

Total Body Weight ◽

Seminal Vesicles ◽

Female Rats ◽

Male Rats ◽

Intact Male ◽

Adult Rats ◽

Organ Weights ◽

Total Body

SUMMARY Adult rats of both sexes were either gonadectomized or hypophysectomized and gonadectomized. Three to eight weeks later they were treated for 14 consecutive days with oil or with 75 or 200 μg testosterone propionate (TP) per 100 g body weight. The animals were killed and for each sex the gonadectomized animals were compared with the hypophysectomized-gonadectomized animals as far as their NADPH- and NADH-dependent 3α-hydroxysteroid dehydrogenases (3α-HSD) in renal microsomes, transcortin levels in serum and five organ weights relative to total body weight were concerned. For two of the latter, i.e. the relative kidney and prostatic weights, no significant differences were found. Transcortin levels, relative adrenal weights and renal NADPH-dependent 3α-HSD activities were higher in oil-treated gonadectomized animals than in oil-treated hypophysectomized-gonadectomized animals. The opposite was found for the relative weights of uterus and seminal vesicles and renal NADH-dependent 3α-HSD activities. These differences between gonadectomized and hypophysectomized-gonadectomized animals disappeared after TP treatment as far as transcortin levels were concerned but remained for the five other parameters. After gonadectomy sexual differences subsisted for all parameters studied. But whereas intact male rats had higher NADH-dependent 3α-HSD activities than female rats the opposite was found after gonadectomy. After gonadectomy plus hypophysectomy the between sex differences disappeared as far as transcortin levels were concerned but remained in the other parameters studied.

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Western diet in the perinatal period promotes dysautonomia in the offspring of adult rats

Journal of Developmental Origins of Health and Disease ◽

10.1017/s2040174416000623 ◽

2016 ◽

Vol 8 (2) ◽

pp. 216-225 ◽

Cited By ~ 4

Author(s):

R. Vidal-Santos ◽

F. N. Macedo ◽

M. N. S. Santana ◽

V. U. De Melo ◽

J. L. de Brito Alves ◽

...

Keyword(s):

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Systolic Arterial Pressure ◽

Perinatal Period ◽

Western Diet ◽

Control Group ◽

Standard Diet ◽

Adult Rats ◽

Male Wistar Rats ◽

The Impact

The present study investigated the impact of a western diet during gestation and lactation on the anthropometry, serum biochemical, blood pressure and cardiovascular autonomic control on the offspring. Male Wistar rats were divided into two groups according to their mother’s diet received: control group (C: 18% calories of lipids) and westernized group (W: 32% calories of lipids). After weaning both groups received standard diet. On the 60th day of life, blood samples were collected for the analysis of fasting glucose and lipidogram. Cardiovascular parameters were measured on the same period. Autonomic nervous system modulation was evaluated by spectrum analysis of heart rate (HR) and systolic arterial pressure (SAP). The W increased glycemia (123±2v. 155±2 mg/dl), low-density lipoprotein (15±1v. 31±2 mg/dl), triglycerides (49±1v. 85±2 mg/dl), total cholesterol (75±2v. 86±2 mg/dl), and decreased high-density lipoprotein (50±4v. 38±3 mg/dl), as well as increased body mass (209±4v. 229±6 g) than C. Furthermore, the W showed higher SAP (130±4v. 157±2 mmHg), HR (357±10v. 428±14 bpm), sympathetic modulation to vessels (2.3±0.56v. 6±0.84 mmHg2) and LF/HF ratio (0.15±0.01v. 0.7±0.2) than C. These findings suggest that a western diet during pregnancy and lactation leads to overweight associated with autonomic misbalance and hypertension in adulthood.

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