THE HYPOTHALAMUS AND PROPYLTHIOURACIL-INDUCED GOITRE IN THE RAT

1963 ◽  
Vol 42 (2) ◽  
pp. 254-262 ◽  
Author(s):  
J. J. van der Werff ten Bosch ◽  
H. E. Swanson

ABSTRACT Adult female rats were given a normal diet, or a diet which contained 0.15% propylthiouracil. At the beginning of the experiment one half of the rats were left intact, whilst the others received an electrolytic basal midline lesion in the anterior hypothalamus. Of each of the four groups of rats, one half was killed after 14 days, the others after 28 days. It was found (both after 14 and after 28 days) that the presence of a lesion reduced the thyroid weight to approximately 75% of the value in intact rats on the same diet, which might be normal or contain propylthiouracil. Propylthiouracil caused thyroid enlargement (to 278% after 14 days and 352–360% after 28 days) in intact rats as compared with intact rats on a normal diet, and in lesioned rats as compared with lesioned rats on a normal diet. It is concluded that lesions cause a lowered steady state of the thyroid-pituitary feed-back system, but that this system responds normally to the alteration of the steady state caused by the propylthiouracil-induced block in thyroid hormone output.

1995 ◽  
Vol 146 (1) ◽  
pp. 87-94 ◽  
Author(s):  
J A M Mattheij ◽  
J J M Swarts ◽  
P Lokerse ◽  
J T van Kampen ◽  
D Van der Heide

Abstract The pituitary-ovarian axis was studied after withdrawal of thyroid hormone in 131I-radiothyroidectomized adult female rats. Oestrous cycles became prolonged and irregular within 2 weeks after the supply of thyroid hormone was stopped. If an LH surge occurred in hypothyroid rats on the day of vaginal pro-oestrus it was significantly greater in rats which had been made hypothyroid for 4–5 weeks than in controls; in hypothyroid rats with an LH surge on pro-oestrus, plasma progesterone showed a rise similar to that in controls at pro-oestrus; the ovulation rate was decreased in hypothyroid rats. About half of the rats from which blood was sampled daily in the afternoon between 7 and 18 days after tri-iodothyronine (T3) withdrawal had 1 day of pro-oestrus; on this day the LH surge was higher than in controls. On days 2 and 1 before and days 1 and 2 after this pro-oestrus, plasma progesterone was similar to that of controls on days 2 and 1 before and days 1 and 2 after pro-oestrus respectively. However, progesterone was higher in the period before and after these days. The other hypothyroid rats showed no pro-oestrus and no LH surge during this period, while their plasma progesterone levels were high on all days. On the morning of day 10 after T3 withdrawal and 5 days after the preceding pro-oestrus, most hypothyroid rats had high progesterone and low oestradiol plasma levels. In these rats, injection of gonadotrophin-releasing hormone caused a relatively small increase in LH; it did not stimulate the secretion of oestradiol or progesterone, and it did not induce ovulation. It was concluded that hypothyroidism induces major changes in the secretion of steroids by corpora lutea and growing follicles. Whether the changed steroid metabolism is the primary cause of the observed prolongation of the oestrous cycles, the increased pro-oestrous LH surge and the reduced ovulation rate remains to be investigated. Journal of Endocrinology (1995) 146, 87–94


1963 ◽  
Vol 26 (3) ◽  
pp. 425-436 ◽  
Author(s):  
P. S. BROWN

SUMMARY A dithiocarbamoylhydrazine (ICI 33828) was injected s.c. into intact rats and mice. It usually caused a reduction in weight of the uterus or of the accessory organs in the male, but less commonly of the gonads. As little as 0·5 mg. daily for 4 days caused significant effects in adult female rats, while half this dose on alternate days retarded maturation in male rats. ICI 33828 was injected with exogenous gonadotrophin in three systems of assay and in some cases it modified the response to the gonadotrophin. This may not be due to a specific effect at the gonadal level but either to suppression of endogenous gonadotrophins in the test animals or to the effect of ICI 33828 on their general condition. Pituitary glands from male rats treated with ICI 33828 were assayed for follicle stimulating hormone (FSH) and found to contain significantly less than glands from control rats. This suggests that ICI 33828 acts by reducing the formation of pituitary gonadotrophin.


1981 ◽  
Vol 90 (1) ◽  
pp. 69-76 ◽  
Author(s):  
W. P. HERMANS ◽  
M. H. M. DEBETS ◽  
E. C. M. VAN LEEUWEN ◽  
F. H. DE JONG

The time-related changes in gonadotrophin concentrations after a single injection of steroid-free bovine follicular fluid (bFF), which contains material with inhibin-like activity, were studied in 25-day-old and adult female rats which either were intact or had been ovariectomized 2 days before. In ovariectomized and intact rats administration of bFF caused a selective suppression of FSH after 4–8 h in 25-day-old rats and after 3–4 h in adult rats. No systematic changes in concentrations of LH after bFF injection were observed. Relative suppression of FSH levels in adult rats was more pronounced and of longer duration than in 25-day-old rats. Moreover, the total period of suppression lasted longer in ovariectomized than in intact rats (12 and 8 h for 25-day-old and 24 and 15 h for adult rats respectively). Hypersecretion of FSH was found in intact rats after the initial suppression; this phenomenon was more pronounced and of longer duration in adult than in 25-day-old rats. No clear change in the numbers of healthy growing follicles was observed after injection of bFF into intact rats. These results indicate that the pituitary secretion of FSH responds quickly and selectively after administration of bFF to intact and ovariectomized, 25-day-old and adult female rats. The hypersecretion of FSH in intact rats might compensate for the initial suppression of this gonadotrophin, and may thus ensure the maturation of a normal number of follicles.


2017 ◽  
Vol 37 (9) ◽  
pp. 1002-1014 ◽  
Author(s):  
Cíntia A. Souza ◽  
Juneo F. Silva ◽  
Camila L.R. Silva ◽  
Natália M. Ocarino ◽  
Rogéria Serakides

ABSTRACT: This study aimed to evaluate the effects of thyroid hormone on the decidua and metrial gland of rats and to examine the expression of angiogenic factors. 72 adult, female rats were divided into hypothyroid, T4-treated2, and control groups. At 10, 14 and 19 days of gestation (DG), the decidua and metrial gland were collected for histomorphometric and immunohistochemical evaluation of the expression of VEGF, Flk-1 and Tie-2. Hypothyroidism reduced the area of the decidua at 10 and 19 DG. Furthermore, VEGF was increased at 10 and 14 DG, and Flk-1 only at 14 DG, but both was reduced at 19 DG in the metrial gland without significantly changing the area occupied by blood vessels. Rats treated with T4 showed an increase in the decidua blood vessels at 10 and 19 DG. However, at 10 DG, excess T4 resulted in increased of Flk-1 in the decidua and metrial gland. Hypothyroidism increased the Tie-2 at 10 and 19 DG in the decidua and metrial gland. In conclusion, hypothyroidism reduces the area of the decidua and increases the expression of VEGF, Tie-2 and Flk-1. The excess of T4 promotes tissue angiogenesis by increasing the number of vessels in the decidua because of the increased expression of Flk-1.


1962 ◽  
Vol 41 (2) ◽  
pp. 301-313 ◽  
Author(s):  
S. Horowitz ◽  
J. J. Van der Werff ten Bosch

ABSTRACT Electrolytic lesions were placed in the anterior hypothalamus of 3–4 day-old female rats; vaginal opening was hastened in comparison with blank-operated littermates in 12 of 17 rats bearing a lesion in the basal supra-and post-chiasmatic area. In the animals with the earliest vaginal opening, lesions reached upward towards the region of the anterior commissure and the paraventricular nuclei. The degree of advancement of puberty in rats operated at the age of 3 or 4 days was similar to that caused by lesions made at 10, 14 or 15 days. This finding suggests that the effect of a lesion upon gonadotrophin secretion does not begin to take place until after the age of at least two weeks.


1965 ◽  
Vol 48 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Herbert Schriefers ◽  
Gerlinde Scharlau ◽  
Franzis Pohl

ABSTRACT After the administration of anabolic steroids to adult female rats in daily doses of 1 mg per animal for 14 days, the following parameters were investigated: the rate of the Δ4-5α-hydrogenase-catalyzed cortisone reduction in liver slices and microsomal fractions, the adrenal weight and the in vitro corticosterone production rate. Among the steroids tested, only 17α-methyl-testosterone and 17α-ethyl-19-nor-testosterone were effective in lowering significantly cortisone reduction rate by liver slices with concomitant decreases in microsomal Δ4-5α-hydrogenase-activity. Testosterone, 19-nor-testosterone, 17α-ethinyl-19-nor-testosterone, 17α-methyl-17β-hydroxy-androsta-1,4-dien-3-one and 1-methyl-17β-hydroxy-androst-1-en-3-one were ineffective or only slightly effective. Adrenal weight and absolute corticosterone production rate (μg/60 min per animal) were decreased after treatment with 17α-methyl-testosterone, 17α-ethyl-19-nor-testosterone and 1-methyl-17β-hydroxy-androst-1-en-3-one. Corticosterone production was decreased with 17α-ethinyl-19-nor-testosterone in spite of an unchanged adrenal weight. The relative corticosterone production rate (μg/60 min · 100 mg adrenal) was in any cases unaffected. According to these results there exists – with the exception of 17α-ethinyl-19-nor-testosterone – a strict parallelism between corticosteroid turnover and corticosterone production rate: unchanged turnover is correlated with unchanged corticosterone production rate, while a decreased turnover is correlated with decreased adrenal activity. The protein-anabolic effect of certain anabolic steroids may be partly due to an anti-catabolic action of these compounds resulting from a decreased corticosteroid inactivation and production rate. Possible mechanisms by which anabolic steroids may affect corticosteroid-balance are discussed.


1959 ◽  
Vol XXXII (II) ◽  
pp. 167-176 ◽  
Author(s):  
Walter Schätzle

ABSTRACT In normal adult female rats a single injection of 5 IU corticotrophin was followed by a retention of glucoproteid material in the anterior lobe of the hypophysis and by impairment of the luteinization. In spayed adult female rats the same corticotrophin administration caused stratification and mucification of the vaginal epithelium.


Author(s):  
Bita Barghi ◽  
Majid Shokoohi ◽  
Amir Afshin Khaki ◽  
Arash Khaki ◽  
Maryam Moghimian ◽  
...  

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