scholarly journals COMPARATIVE STUDIES ON THE GROWTH-PROMOTING EFFECTS OF GROWTH HORMONE (STH) AND SALIVARY-GLAND PRINCIPLE (PAROTIN) IN THE HYPOPHYSECTOMIZED AND/OR SIALOADENEC TOMIZED IMMATURE FEMALE RATS II. EFFECTS ON THE PROXIMAL EPIPHYSIS OF THE TIBIA

1957 ◽  
Vol 4 (3) ◽  
pp. 204-213 ◽  
Author(s):  
SHIGEO HONJO ◽  
TOMONORI IMAMICHI ◽  
TEIICHI ETO
2000 ◽  
pp. 517-523 ◽  
Author(s):  
MA Rol De Lama ◽  
A Perez-Romero ◽  
JA Tresguerres ◽  
M Hermanussen ◽  
C Ariznavarreta

OBJECTIVE: A novel non-invasive technique termed microknemometry, which allows daily leg length measurement, was used to investigate the growth promoting effect of growth hormone (GH) on peripubertal rats. We compared the effect of different patterns of recombinant human (rh) GH administration to peripubertal male rats with the effect produced by two daily administrations of the same amount of rhGH to peripubertal female rats or adult male rats. Another group of peripubertal male rats was also submitted to a 3-day period of starvation, in order to study catch-up growth during refeeding and to determine whether this process could be stimulated by exogenous GH administration. RESULTS: GH treatment was unable to stimulate tibial growth or weight gain in peripubertal males, whereas a clear growth promoting effect was observed in female rats and also in adult male rats. Starvation caused a dramatic body weight loss, and a reduction in tibial growth rate. Peripubertal male rats gained body weight faster than unstarved animals during refeeding, although recovery was not complete after nine days. Tibial growth, however, was resumed at the same speed as in normally fed males. This means that no catch-up effect was observed after refeeding in animals either with or without GH treatment. CONCLUSIONS: During peripuberty, normal male rats grow at a maximal speed that cannot be further increased by exogenous GH treatment, whereas age-matched female rats or older males grow at a slower rate than peripubertal males. Thus, exogenous rhGH administration is capable of enhancing growth velocity.


1966 ◽  
Vol 35 (4) ◽  
pp. 393-399 ◽  
Author(s):  
H. AILABOUNI ◽  
S. DIKSTEIN ◽  
U. ZOR ◽  
F. G. SULMAN

SUMMARY The effect of hormones on the 'tibia test' in intact immature female rats has been studied. It was found that corticotrophin, hydrocortisone, dexamethasone, oestradiol, thyroidectomy and pancreatectomy inhibit the growth of epiphysial cartilage, while somatotrophic hormone (STH) and, to a lesser extent, insulin, testosterone, thyroxine, triiodothyronine and aldosterone stimulate it. Dehydroepiandrosterone, progesterone, deoxycorticosterone and prolactin did not affect cartilage growth. Consequently, the 'tibia test' in intact immature female rats can only be considered specific for STH if interference with cartilage growth by the above mentioned hormones can be excluded. This does not detract from the usefulness of the 'tibia test' in intact female rats for studies of growth-promoting or growthinhibiting substances.


2009 ◽  
Vol 47 (4) ◽  
pp. 268-273 ◽  
Author(s):  
I.S.R. Nidhiya ◽  
K.S.R. Pai ◽  
C. Mallikarjuna Rao

1964 ◽  
Vol 206 (5) ◽  
pp. 1137-1144 ◽  
Author(s):  
Robert L. Hazelwood ◽  
Barbara S. Hazelwood

Homogenates of adenohypophysial tissue obtained from alloxan-injected adult male rats varying in duration and severity of diabetes, as well as from diabetic rats maintained on an insulin-replacement regimen, were assayed in immature hypophysectomized female rats. The ability of these crude hypophysial extracts to encourage tibial cartilage width expansion, gain in body weight, and to depress hematocrit and blood urea levels was determined. Significant decrements in ability to increase epiphysial cartilage width and ability to depress hematocrits were noted 14 to 28 days following injection of alloxan. Increasing the intensity of the diabetic state was associated with decreased growth-promoting potency of hypophysial preparations as well as with decreased ability to influence hematological indices. Hypophysial extracts taken from insulin-treated diabetic rats contained more growth hormone than equivalent amounts of tissue obtained from control rats. It is concluded that the adenohypophyses of diabetic rats contain diminished amounts of growth hormone and that insulin repairs or encourages greater than normal accumulation of somatotrophin in these animals.


Author(s):  
T. M. Crisp ◽  
F.R. Denys

The purpose of this paper is to present observations on the fine structure of rat granulosa cell cultures grown in the presence of an adenohypophyseal explant and to correlate the morphology of these cells with progestin secretion. Twenty-six day old immature female rats were given a single injection of 5 IU pregnant mares serum gonadotropin (PMS) in order to obtain ovaries with large vesicular follicles. At 66 hrs. post-PMS administration (estrus indicated by vaginal smear cytology), the ovaries were removed and placed in a petri dish containing medium 199 and 100 U penicillin/streptomycin (P/S)/ml. Under a 20X magnification dissecting microscope, some 5-8 vesicular follicles/ovary were punctured and the granulosa cells were expressed into the surrounding medium. The cells were transferred to centrifuge tubes and spun down at 1000 rpm for 5 mins.


Zygote ◽  
2021 ◽  
pp. 1-7
Author(s):  
Stéphanie Ouabo Meguem ◽  
Landry Lienou Lienou ◽  
Marie Stéphanie Chekem Goka ◽  
Richard Simo Tagne ◽  
Didiane Mefokou Yemele ◽  
...  

Summary Dicliptera verticillata is a medicinal plant traditionally used in western Cameroon to cure female infertility. This experiment was designed to assess the effects of the aqueous extract of Dicliptera verticillata (AEDv) on fertility and gestation in female rats. Oral increasing doses of AEDv were administered to immature female rats over 20 d. After this time, some animals were mated with fertile males and some fertility parameters were assayed; the other animals were euthanized for preliminary toxicity parameters analysis. The effects of AEDv on the different stages of gestation were assayed on selected animals previously controlled for estrous cycle regularity and mated. AEDv led to an increase in serum, uterine and ovarian proteins as well as in ovarian and uterine weights (P < 0.05) in immature female rats. Hepatic proteins significantly decreased (P < 0.01) in high dose-treated animals (50 and 100 mg/kg) compared with controls. The number of implantation sites and the fertility rate were significantly lower (P < 0.05), while the antifertility activity increased significantly (P < 0.05) in treated rats compared with controls. When administered from the 1st to the 5th day of pregnancy, AEDv led to a decrease of more than 60% in the implantation rate in high dose-treated rats (50, 100, and 400 mg/kg). From the 6th to the 9th day, the implantation, gestation rates and the number of fetuses decreased significantly in all treated groups. From the 11th to the 20th day, a 50% resorption and decrease in gestation rate were reported in 50 mg/kg dose-treated animals. AEDv possesses weak contraceptive and abortifacient effects during pregnancy.


1967 ◽  
Vol 39 (1) ◽  
pp. 53-60 ◽  
Author(s):  
W. C. ADAMS ◽  
J. H. LEATHEM

SUMMARY Immature female rats were fed thiouracil for 30 days and injected with 10 i.u. human chorionic gonadotrophin (HCG) for the last 20 days. In thiouracil-fed animals, HCG produced large ovaries containing follicular cysts. These ovaries showed a subnormal concentration of cholesterol but both a normal total content and normal incorporation of [1-14C]acetate into digitonin-precipitable-sterols. Liver and serum cholesterol concentrations were reduced, but in vivo, 4 hr. incorporation of acetate into sterols was doubled suggesting either an acceleration of cholesterol turnover or delayed utilization of sterol precursors of cholesterol. HCG also reduced ovarian cholesterol concentration in euthyroid animals but total organ content and incorporation of [14C]acetate were not altered, nor were liver and serum cholesterol affected. Since the effect of induced ovarian cysts on sterol metabolism cannot be accounted for by known effects of thyroid or gonadal hormones it is suggested that influences of steroid hormones on lipid metabolism may be greatly modified in thyroid deficiency.


1982 ◽  
Vol 100 (1) ◽  
pp. 25-30 ◽  
Author(s):  
Oddvar Naess ◽  
Egil Haug ◽  
Arne Attramadal ◽  
Kaare M. Gautvik

Abstract. Progesterone and corticosterone have a similar effect on the production of growth hormone (GH) and prolactin (Prl) by pituitary tumour cells (GH3 cells) in culture. Previously we have shown that progesterone has a high affinity for the glucocorticoid receptors in these cells. Progesterone may therefore exert its effects through binding to the glucocorticoid receptor. The aim of the present study was to investigate if the GH3 tumour cells and an oestrogen induced pituitary tumour, which also produce GH and Prl, possess specific receptors for progesterone. Both the GH3 tumours and the oestrogen induced pituitary tumour were in fact found to possess cytoplasmatic receptor molecules for progesterone by using the potent progestin R5020 as a marker. Isoelectric focusing revealed one binding component (pH 5.9), which was of protein nature. The binding was of high affinity (Kd 2 × 10−9 mol/l). In the oestrogen induced tumour, the maximal binding was 70 fmol/mg cytosol protein. In female rats with GH3 tumours the binding was 55 fmol/mg cytosol protein. Priming of the animals with 1 mg oestradiol-valerate increased the binding to 116 fmol/mg cytosol protein, whereas very little binding was found in GH3 tumours from rats castrated 7 days before sacrifice. The receptors in the oestrogen induced pituitary tumour and the GH3 tumours exhibited high affinity for R5020 and progesterone, whereas corticosterone had no significant affinity for the receptors. Using exchange assay, it was demonstrated that the cytoplasmic progestin receptors could be translocated to the nucleus after administration of progesterone to the animals. Thus, the presence of specific progesterone receptors, different from the glucocorticoid receptors, strongly indicates that the effects of progesterone on GH and Prl production are mediated through the progesterone receptors.


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