THE EFFECT OF CERTAIN ANDROGENIC STEROIDS ON THE UPTAKE OF RADIOSULPHUR IN A HEALING FRACTURED BONE IN THE RAT

1957 ◽  
Vol 35 (10) ◽  
pp. 771-776 ◽  
Author(s):  
K. Kowalewski ◽  
R. T. Morrison

The uptake of radiosulphur in the fractured and intact humerus of male rats was determined in normal and in castrated animals and the ratio F/I of radioactivity of fractured (F) to intact (I) bone was calculated. Castration resulted in a significant decrease of F/I ratio, as compared with normal control rats.The effect of testosterone propionate and 17-ethyl-19 nortestosterone (Nilevar) on the S35 uptake in bones was studied. Testosterone administration resulted in a slight increase of the F/I in castrated rats, but had no effect on this ratio in intact animals. Both castrated and intact rats treated with Nilevar exhibited a significant rise of S35 uptake in fractured bones and, consequently, high F/I ratios. It is suggested that Nilevar has a marked effect on the synthesis of chondroitin sulphate in the collagen tissues of healing fractures, as measured by the described S35 uptake technique.

1957 ◽  
Vol 35 (1) ◽  
pp. 771-776 ◽  
Author(s):  
K. Kowalewski ◽  
R. T. Morrison

The uptake of radiosulphur in the fractured and intact humerus of male rats was determined in normal and in castrated animals and the ratio F/I of radioactivity of fractured (F) to intact (I) bone was calculated. Castration resulted in a significant decrease of F/I ratio, as compared with normal control rats.The effect of testosterone propionate and 17-ethyl-19 nortestosterone (Nilevar) on the S35 uptake in bones was studied. Testosterone administration resulted in a slight increase of the F/I in castrated rats, but had no effect on this ratio in intact animals. Both castrated and intact rats treated with Nilevar exhibited a significant rise of S35 uptake in fractured bones and, consequently, high F/I ratios. It is suggested that Nilevar has a marked effect on the synthesis of chondroitin sulphate in the collagen tissues of healing fractures, as measured by the described S35 uptake technique.


1970 ◽  
Vol 47 (2) ◽  
pp. 219-224 ◽  
Author(s):  
A. J. THODY ◽  
S. SHUSTER

SUMMARY Adult male rats which had been castrated prepuberally secreted less sebum than intact rats. When hypophysectomy followed castration there was a further decrease in sebum secretion. Treatment of the castrated and hypophysectomized castrated rats with testosterone propionate produced a large and comparable increase in the sebum secretion of both groups. Testosterone propionate also caused a marked increase in the preputial gland weight of the castrated rats, although a much smaller response occurred after hypophysectomy. The effect of hypophysectomy on the response of the sebaceous and preputial glands to testosterone is discussed.


1996 ◽  
Vol 317 (1) ◽  
pp. 97-102 ◽  
Author(s):  
Chiharu TOHYAMA ◽  
Junko S. SUZUKI ◽  
Shino HOMMA ◽  
Mika KARASAWA ◽  
Toshio KUROKI ◽  
...  

Metallothioneins (MTs) are a group of cysteine-rich heavy-metal-binding proteins. We have investigated MT gene expression in the ventral and dorsolateral lobes of the prostate and coagulating gland of male Wistar rats. In intact rats, both MT mRNA and MT were present in the dorsolateral lobe and coagulating gland but not in the ventral lobe. Orchidectomy caused involution of the above organs, and both MT mRNA and MT were considerably decreased or became undetectable. An injection of testosterone propionate into orchidectomized rats restored not only the size of these organs, but also MT mRNA and MT concentrations, particularly in the dorsolateral lobe and coagulating gland. In the dorsolateral lobe, no selective uptake of Zn2+ preceding the increase in MT was observed, suggesting that Zn2+ ions are not associated with the increased expression of the MT gene. The present result suggests that of the male auxiliary genital organs, the dorsolateral lobe and coagulating gland, but not the ventral lobe, contain MT, the biosynthesis of which is regulated by testosterone.


1979 ◽  
Vol 180 (2) ◽  
pp. 313-318 ◽  
Author(s):  
Coral A. Lamartiniere ◽  
Cindy S. Dieringer ◽  
Etsuko Kita ◽  
George W. Lucier

The hepatic microsomal enzyme UDP-glucuronyltransferase undergoes a complex developmental pattern in which enzyme activity is first detectable on the 18th day of gestation in rats. Prepubertal activities are similar for males and females. However, postpubertal sexual differentiation of enzyme activity occurs in which male activities are twice those of females. Neonatal administration of testosterone propionate or diethylstilboestrol to intact animals resulted in lowered UDP-glucuronyltransferase activity in liver microsomal fractions of adult male rats, whereas no changes were observed in the adult females and prepubertal male and female animals. Neonatal administration of testosterone propionate and diethylstilboestrol adversely affected male reproductive-tract development as evidenced by decreased weights of testes, seminal vesicles and ventral prostate. Diethylstilboestrol also markedly decreased spermatogenesis. Hypophysectomy of adult male rats resulted in negative modulation of microsomal UDP-glucuronyltransferase and prevented the sexual differentiation of enzyme activity. In contrast hypophysectomy had no effect on female UDP-glucuronyltransferase activity. A pituitary transplant under the kidney capsule was not capable of reversing the enzyme effects of hypophysectomy, therefore suggesting that the male pituitary factor(s) responsible for positive modulation of UDP-glucuronyltransferase might be under hypothalamic control in the form of a releasing factor. Neonatal testosterone propionate and diethylstilboestrol administration apparently interfered with the normal sequence of postpubertal UDP-glucuronyltransferase sexual differentiation.


Author(s):  
Doraswamy Gangaraju ◽  
Shanmugam Bhasha ◽  
Ravi Sahukari ◽  
Shanmugam Kondeti Ramudu ◽  
Srinivas Kurakula ◽  
...  

A disruption in the equilibrium between the generation of reactive oxygen species and antioxidant defense enzymes is referred to as oxidative stress. In the present study, we planned to identify the hepatoprotective effect of Phyllanthus amarus alkaloid rich fraction in wistar strain albino male rats. The hepatic damage was induced by the D-galactosamine and ameliorative effect was tested with alkaloid rich fraction of P. amarus by measuring oxidative stress markers such as G6PDH, LDH, SDH, MDH and GDH in the liver tissue. Activity levels of G6PDH, SDH, MDH and GDH were significantly decreased in D-galactosamine induced hepatitis rats when compare to normal control rat group, while their activities were significantly increased in hepatitis rat group that supplemented with alkaloid rich fraction of P. amarus. In contrast, LDH enzyme activity of liver was significantly increased in the hepatitis rat group when compare to normal control rats, while its activity was significantly decreased in hepatitis rats treated with alkaloid fraction. In conclusion, it is very clear that alkaloid fraction of P. amarus has hepatoprotective property with respect of decreasing oxidative stress by regulating oxidative stress marker enzymes. The isolation and identification of specific alkaloid compounds with hepatoprotective properties and anti-oxidative stress will require much further research.


2018 ◽  
Vol 99 (5) ◽  
pp. 775-778
Author(s):  
A O Lobkarev ◽  
R Kh Khafiz’yanova ◽  
O A Lobkarev

Aim. To study the effect of testosterone on the rate of oxygen consumption by rodent prostate homogenate. Methods. The study included 30 healthy old white outbred male rats divided into two groups with 15 animals in each group. The rats of the first group were administered the application of 1 % testosterone-containing gel Androgel before the operation. The rats of the second group received no testosterone. Under anesthesia prostatectomy was performed. Homogenate was immediately prepared from each prostate. Further every homogenate was placed into 250 ml vial to determine the rate of oxygen consumption. Then the device measuring the concentration of oxygen dissolved in water was placed into the vial, and the air-tightness was created. Each vial was put into the thermostat for 30 minutes at 36.6 ˚C. Then the measurement of the concentration of O2 dissolved in the water was performed. Results. Application of transdermal gel with 1 % testosterone was found to cause increase of oxygen consumption by prostate tissue. This fact can explain why the clinical effectiveness of testosterone is individual to each patient with benign prostatic hyperplasia (BPH) and chronic prostatitis (CP): oxygen supply to the prostate is different in each patient with BPH and CP. So not in every patient the oxygen-transporting system is capable of supplying prostate tissues with the amount of oxygen according to increasing demand of the organ on testosterone administration. Conclusion. Testosterone increases the rate of oxygen consumption by prostate tissue.


1974 ◽  
Vol 142 (2) ◽  
pp. 273-277 ◽  
Author(s):  
Jan-Åke Gustafsson ◽  
Åke Pousette

The regulatory mechanisms involved in the control of the nuclear NADPH-dependent 3-ketosteroid 5α-reductase (5α-reductase) activity were studied in liver, kidney and prostate. The substrate used was [1,2-3H]androst-4-ene-3,17-dione (androstenedione) (for liver and kidney) or [4-14C]androstenedione (for prostate). The hepatic nuclear 5α-reductase activity was greater in female than in male rats, was greater in adult than in prepubertal female rats, increased after castration of male rats, but was not affected by treatment with testosterone propionate or oestradiol benzoate. These regulatory characteristics are in part different from those previously described for the hepatic microsomal 5α-reductase. The renal nuclear metabolism of androstenedione, i.e. 5α reduction and 17β-hydroxy steroid reduction, was relatively unaffected by sex, age, castration and treatment with testosterone propionate. However, treatment of castrated male rats with oestradiol benzoate led to a significant increase in the 5α-reductase activity and a significant decrease in the 17β-hydroxy steroid reductase activity. Finally, the nuclear 5α-reductase activity in prostate was androgen-dependent, decreasing after castration and increasing after treatment with testosterone propionate. In conclusion, the nuclear 5α-reductase activities in liver, kidney and prostate seem to be under the control of distinctly different regulatory mechanisms. The hypothesis is presented that whereas the prostatic nuclear 5α-reductase participates in the formation of a physiologically active androgen, 5α-dihydrotestosterone, this may not be the true function of the nuclear 5α-reductase in liver and kidney. These enzymes might rather serve to protect the androgen target sites in the chromatin from active androgens (e.g. testosterone) by transforming them into less active androgens (e.g. 5α-androstane-3,17-dione and/or 5α-dihydrotestosterone).


1973 ◽  
Vol 59 (3) ◽  
pp. 539-544 ◽  
Author(s):  
VARAPAN DANUTRA ◽  
MAUREEN E. HARPER ◽  
K. GRIFFITHS

SUMMARY Male Sprague—Dawley rats were injected (i.m.) daily for 10 days with 100 μg of either oestradiol-17β, diethylstilboestrol (DES), dl-dihydrodibutylstilboestrol (dl-DHBS) or meso-dihydrodibutylstilboestrol (meso-DHBS) in 0·2 ml sesame oil. After 10 days, the testicular tissue was removed and incubated simultaneously with [7α-3H]dehydroepiandrosterone and [4-14C]17α-hydroxyprogesterone. Less testosterone was synthesized by the testicular tissue from animals treated with oestradiol-17β, DES and meso-DHBS than by the controls or animals treated with dl-DHBS. The decreased synthetic activity was related to the decreased activity of both the 17β-hydroxysteroid dehydrogenase and 17α-pregnene-C17, 20-lyase enzyme systems. Prostatic tissue was also incubated with [7α-3H]testosterone. Administration of DES, oestradiol-17β or meso-DHBS increased the metabolism of testosterone by the prostatic tissue with a marked effect on the 5α-reductase enzyme system.


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