Effects of Prenatal Stress on the Activity of an Enzyme Involved in Neurosteroid Synthesis During the “Critical Period” of Sexual Differentiation of the Brain in Male Rats

2005 ◽  
Vol 35 (9) ◽  
pp. 931-935 ◽  
Author(s):  
N. E. Ordyan ◽  
S. G. Pivina
Keyword(s):  
Sexual Differentiation ◽  
Prenatal Stress ◽  
Critical Period ◽  
Male Rats ◽  
The Brain

scholarly journals A single neonatal administration of soybean oil and/or tamoxifen affects permanently the testis histomorphology in adult rats.

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Alicia González-González ◽  
Everardo González-Padilla ◽  
Francisco Fierro-Fierro ◽  
María De Lourdes Juárez-Mosqueda ◽  
Juan José Pérez-Rivero ◽  
...  
Keyword(s):  
Soybean Oil ◽  
Sexual Differentiation ◽  
Critical Period ◽  
Male Rats ◽  
Histological Evaluation ◽  
Seminiferous Tubules ◽  
Control Group ◽  
Adult Rats ◽  
Testicular Weight ◽  
Neonatal Administration

The aim of this study was to determine the effect of tamoxifen (Tx) and its vehicle, soybean oil (SO), during the critical period of hypothalamic sexual differentiation in newborn male rats, regarding gonadal histomorphology during adulthood. The animals were randomly divided into 3 groups (n = 5 each). An hour after birth, one group was treated subcutaneously with 200 μg of Tx, using commercial SO (20 uL) as a vehicle; another group was treated with only 20 μL of SO; the control group received no treatment. All rats were weighed and sacrificed by cervical dislocation on day 90 post-treatment. Testicles were removed, weighed and processed for histological evaluation. The single administration of Tx and/or SO during the critical period of sexual differentiation of the hypothalamus permanently altered testicular histomorphology, spermatogenesis, and body weight in adulthood. Alterations included vacuolization and reduction in the number of spermatogonia and Sertoli cells. The administration of Tx reduced the testicular weight, the diameter and area of the seminiferous tubules, and the height of the germinal epithelium, and increased the intertubular space. Soybean oil by itself reduced the number of spermatocytes and spermatids more than Tx did. There was no effect on the number of Leydig cells. The possibility that soybean oil can act as an endocrine disruptor deserves greater attention and opens the possibility for the development of new methods of pest control.

EFFECT OF A SINGLE INJECTION OF CHLORPROMAZINE INTO INFANT MALE RATS ON SUBSEQUENT GONADOTROPHIN SECRETION

1970 ◽  
Vol 48 (2) ◽  
pp. 151-NP ◽  
Author(s):  
W. LADOSKY ◽  
W. M. KESIKOWSKI ◽  
I. F. GAZIRI
Keyword(s):  
Body Weight ◽  
Luteinizing Hormone ◽  
Sexual Differentiation ◽  
Single Injection ◽  
Male Rats ◽  
Postnatal Life ◽  
Gonadotrophin Secretion ◽  
The Brain ◽  
Infant Male

SUMMARY A single injection of 20 μg chlorpromazine/g body weight into male rats 10 days after birth accelerated spermatogenesis when the animals were 45 days old; this was not observed in rats injected on days 1, 5, 8, 12 or 15 of life. When half an ovary was grafted into the eye of rats treated on day 10, they showed a higher incidence of luteinization than ovarian grafts in rats treated at any other age. Compared with animals surgically castrated at the same age, chlorpromazine did not act as by 'pharmacological castration', but induced some alteration in the brain which promoted higher secretion of luteinizing hormone, characteristic of the female pattern of gonadotrophin control, as demonstrated by accelerated spermatogenesis and a higher degree of luteinization. These results suggest that the sexual differentiation of the brain occurs on about the 10th day of postnatal life and can be blocked by chlorpromazine.

EFFECTS OF DIHYDROTESTOSTERONE AND OESTRADIOL ON SEXUAL DIFFERENTIATION IN MALE RATS

1980 ◽  
Vol 84 (3) ◽  
pp. 397-407 ◽  
Author(s):  
P. VAN DER SCHOOT
Keyword(s):  
Sexual Differentiation ◽  
Testosterone Propionate ◽  
Neonatal Period ◽  
Combined Treatment ◽  
Female Rats ◽  
Male Rats ◽  
Normal Male ◽  
Oestradiol Benzoate ◽  
The Brain ◽  
Copulatory Behaviour

Adult male rats which had been castrated at birth and treated with the non-aromatizable androgen dihydrotestosterone propionate (DHTP) showed incomplete copulatory behaviour. When tested with oestrous female rats during treatment with testosterone propionate (TP) they readily mounted these females and showed frequent penile intromissions but rarely ejaculated. In a long series of observations the proportion of ejaculating rats in tests of 30 min did not exceed 50%. Neonatally castrated rats treated with DHTP during infancy thus seemed to be capable of ejaculation in adulthood during treatment with TP, but the threshold for the occurrence of the ejaculatory reflex seemed to be higher than in normal male rats. By replacing treatment in adulthood with TP by a combined treatment with DHTP and oestradiol benzoate (OB), the frequency of ejaculation was not increased. It was concluded that the incomplete copulatory behaviour was not due to reduced efficiency of aromatization of androgen within the brain of these rats. The addition of OB to DHTP during the neonatal period of treatment enhanced the frequency of ejaculation in adulthood. The combined treatment of 0·1 mg DHTP on days 1, 3 and 5 with 0·01 mg OB on day 1 made adult copulatory behaviour during treatment with TP indistinguishable from that of rats castrated on day 10 or rats castrated at birth and treated with TP during infancy. It was concluded that the masculine organization of systems and structures involved in the display of male copulatory behaviour occurs under the influence of both non-aromatizable androgen and oestrogen, oestrogen being most likely the substance required to 'organize' the central nervous aspects of the regulation of this behaviour. The absence neonatally of nonaromatizable androgen and/or oestrogen results in specific deficiencies in adult copulatory behaviour as compared with the behaviour of normal male rats.

ANDROGEN CONCENTRATIONS IN PLASMA AND TESTIS OF DEVELOPING RATS

1968 ◽  
Vol 40 (4) ◽  
pp. 485-491 ◽  
Author(s):  
J. A. RESKO ◽  
H. H. FEDER ◽  
R. W. GOY
Keyword(s):  
Sexual Differentiation ◽  
Critical Period ◽  
Neonatal Period ◽  
Testicular Tissue ◽  
Postnatal Period ◽  
Male Rats ◽  
Electron Capture Detection ◽  
Gas Liquid Chromatography ◽  
Testosterone Concentration ◽  
Peripheral Plasma

SUMMARY Testosterone and androstenedione levels in plasma and testicular tissue of developing rats were measured using gas—liquid chromatography with electron capture detection. The major androgen of both the adult and early postnatal period of development was testosterone. Pooled plasma from 230 one-day-old male rats contained 0·027 μg. testosterone/100 ml. The concentration of testosterone in the testes at this age was 0·328 μg./g. wet tissue. With increasing age there was a decline in testosterone concentration in plasma as well as in gonadal tissue which lasted until about the age of 30 days. The period from 40 to 60 days was characterized by an increasing concentration of testosterone in the plasma and gonads. During adulthood, testosterone reached concentrations as high as 0·202 μg./100 ml. peripheral plasma. Androstenedione could not be detected in the circulation during the critical period of neonatal neural sexual differentiation, but it was present in the testes at this stage. In the pubertal and adult stages androstenedione was found in the plasma and testes. Its concentration, particularly in adulthood, was not as great as that of testosterone. These results indicate that testosterone is present in plasma and testicular tissue of the rat during the neonatal period when behavioural and physiological sexual differentiation is presumed to occur.

PEPTIDASE ACTIVITY IN THE HYPOTHALAMI OF RATS TREATED NEONATALLY WITH OESTROGEN

1973 ◽  
Vol 72 (1) ◽  
pp. 9-17 ◽  
Author(s):  
E. C. Griffiths ◽  
K. C. Hooper
Keyword(s):  
Sexual Differentiation ◽  
Critical Period ◽  
Testosterone Propionate ◽  
Marked Decrease ◽  
Reproductive Function ◽  
Female Rats ◽  
Male Rats ◽  
Peptidase Activity ◽  
Rat Hypothalamus ◽  
Lh Secretion

ABSTRACT The previous paper (Griffiths & Hooper 1973) described the activity of certain hypothalamic peptidases following orchidectomy and testosterone propionate injection, and suggested that changes in enzyme levels may be used as an index of gonadotrophin release in male rats, in a similar way to that previously described for female rats (Griffiths & Hooper 1972a). Using this approach, the effect of neonatally administered oestrogen on the hypothalamus was investigated. The marked increase in supernatant activity in male rats and the equally marked decrease in supernatant activity in female rats, both injected during the critical period of hypothalamic sexual differentiation, are interpreted as indicating decreased LH secretion in males and increased LH secretion in females respectively. It can be concluded that the changes in reproductive function produced by neonatally administered oestrogen are caused by alterations in LH-RF metabolism and that the peptidases in the rat hypothalamus are responsible for this metabolism.

IMPORTANCE OF PERINATAL TESTOSTERONE IN SEXUAL DIFFERENTIATION IN THE MALE RAT

1981 ◽  
Vol 91 (1) ◽  
pp. 75-79 ◽  
Author(s):  
F. GOGAN ◽  
A. SLAMA ◽  
B. BIZZINI-KOUTZNETZOVA ◽  
F. DRAY ◽  
C. KORDON
Keyword(s):  
Sexual Differentiation ◽  
Critical Period ◽  
Rapid Decrease ◽  
Female Rats ◽  
Male Rats ◽  
Male Rat ◽  
Fetal Period ◽  
Testosterone Secretion

Testosterone secretion in the male rat was high during the late fetal and immediate postnatal periods. It then showed a rapid decrease 3 h after birth and remained low until puberty. Male rats from mothers given daily injections of an antibody to testosterone during the week before delivery displayed an LH peak when they were adult, orchidectomized and implanted with oestradiol. However, the amplitude of the peak was far smaller than in female rats from the same mothers treated in the same manner. Thus, the critical period during which testosterone triggers hypothalamic sexual differentiation is very close to birth, possibly starting at the end of the fetal period.

Chronic immobilization stress induces anxiety-related behaviors and affects brain essential minerals in male rats

2020 ◽  
pp. 1-8
Author(s):  
Zafer Sahin ◽  
Alpaslan Ozkurkculer ◽  
Omer Faruk Kalkan ◽  
Ahmet Ozkaya ◽  
Aynur Koc ◽  
...  
Keyword(s):  
Immobilization Stress ◽  
Central Area ◽  
Essential Elements ◽  
Male Rats ◽  
Control Group ◽  
Male Wistar Rats ◽  
Swimming Test ◽  
The Brain ◽  
Center Area ◽  
Chronic Immobilization Stress

Abstract. Alterations of essential elements in the brain are associated with the pathophysiology of many neuropsychiatric disorders. It is known that chronic/overwhelming stress may cause some anxiety and/or depression. We aimed to investigate the effects of two different chronic immobilization stress protocols on anxiety-related behaviors and brain minerals. Adult male Wistar rats were divided into 3 groups as follows ( n = 10/group): control, immobilization stress-1 (45 minutes daily for 7-day) and immobilization stress-2 (45 minutes twice a day for 7-day). Stress-related behaviors were evaluated by open field test and forced swimming test. In the immobilization stress-1 and immobilization stress-2 groups, percentage of time spent in the central area (6.38 ± 0.41% and 6.28 ± 1.03% respectively, p < 0.05) and rearing frequency (2.75 ± 0.41 and 3.85 ± 0.46, p < 0.01 and p < 0.05, respectively) were lower, latency to center area (49.11 ± 5.87 s and 44.92 ± 8.04 s, p < 0.01 and p < 0.01, respectively), were higher than the control group (8.65 ± 0.49%, 5.37 ± 0.44 and 15.3 ± 3.32 s, respectively). In the immobilization stress-1 group, zinc (12.65 ± 0.1 ppm, p < 0.001), magnesium (170.4 ± 1.7 ppm, p < 0.005) and phosphate (2.76 ± 0.1 ppm, p < 0.05) levels were lower than the control group (13.87 ± 0.16 ppm, 179.31 ± 1.87 ppm and 3.11 ± 0.06 ppm, respectively). In the immobilization stress-2 group, magnesium (171.56 ± 1.87 ppm, p < 0.05), phosphate (2.44 ± 0.07 ppm, p < 0.001) levels were lower, and manganese (373.68 ± 5.76 ppb, p < 0.001) and copper (2.79 ± 0.15 ppm, p < 0.05) levels were higher than the control group (179.31 ± 1.87 ppm, 3.11 ± 0.06 ppm, 327.25 ± 8.35 ppb and 2.45 ± 0.05 ppm, respectively). Our results indicated that 7-day chronic immobilization stress increased anxiety-related behaviors in both stress groups. Zinc, magnesium, phosphate, copper and manganese levels were affected in the brain.

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