Renaturalizing the sexually dimorphic profiles of circulating growth hormone in hypophysectomized rats

1991 ◽  
Vol 124 (3) ◽  
pp. 283-289 ◽  
Author(s):  
Nisar A. Pampori ◽  
Arun K. Agrawal ◽  
Bernard H. Shapiro

Abstract. Hypophysectomy resulted in a total elimination of measurable circulating growth hormone with an associated loss of body weight gain. The typical sexually dimorphic plasma growth hormone patterns: pulsatile profiles in male rats and tonic-like secretion in female rats, were lost. The male- and female-dependent profiles of plasma growth hormone, monitored from serial blood collections, were restored by administering the hormone through a single electrically controlled external pump attached to an indwelling catheter, and by implanting osmotic pumps intraperitoneally, respectively. Restoring the natural patterns of plasma growth hormone in animals devoid of pituitaries, re-initiated body growth. However, the body weight gains in both sexes of hypophysectomized rats were much greater when rat growth hormone was introduced to the animals in a masculine (pulsatile) pattern that appeared to be independent of pulse frequency, rather than in a continuous feminine profile. Subcutaneous injections, the most commonly reported method of administration, produced low-amplitude, long-lasting plasma peaks that were not as effective as pulse infusion in restoring growth. The procedure allows manipulation of the hormone profile (i.e. number of pulses/day, pulse amplitude, and through duration in the pulsatile pattern, and plasma concentration in the tonic pattern) in order to identify, and thus study the presumed salient components of the pattern regulating growth hormone responses.

1957 ◽  
Vol 35 (1) ◽  
pp. 1113-1118
Author(s):  
George H. Beaton ◽  
Hannah Z. Banky ◽  
Audrey M. Haufschild

Doses of growth hormone which were minimal with respect to body weight increase were sufficient to produce significant alterations in liver alanine – glutamic transaminase and arginase activities and blood urea and amino nitrogen levels. The biochemical effects of the hormone appeared coincident with the body weight increase. Female rats showed a more pronounced response to growth hormone than did male rats. This sex difference was evident with respect to all of the metabolic alterations observed. Although it is not possible to state whether the metabolic alterations are direct effects of the hormone, they do take an integral part in bringing about the over-all biological effect.


2020 ◽  
Vol 70 (2) ◽  
pp. 144-151
Author(s):  
María del Rocío Padilla Galindo ◽  
Alma Gabriela Martínez Moreno ◽  
Fatima Ezzahra Housni ◽  
Zyanya Reyes Castillo ◽  
Erika Saenz-Pardo Reyes

El consumo de stevia ha sido promovido por su bajo aporte calórico, su efecto antidiabético y antihipercolesterolémico. Sin embargo, los efectos de la ingesta de stevia parecen no ser los mismos para las ratas hembras respecto de los machos. El propósito de este estudio fue evaluar el efecto de la ingesta de stevia sobre el consumo de alimento, peso corporal y niveles de glucosa, insulina, colesterol y triglicéridos en ratas hembras Wistar durante 13 semanas y realizar un análisis predictivo del peso corporal y la ingesta de alimento a 20 semanas. Se utilizaron 20 ratas hembras adultas, que se dividieron en 2 grupos: control (CG) y stevia (SG), ambos grupos recibieron agua y comida a libre acceso, así como una solución de stevia al 0,2 % para el grupo SG. Se registró diariamente el consumo de alimento, agua y solución de stevia; la medición del peso corporal se realizó semanalmente. Al final de las 13 semanas de experimentación, los animales se sacrificaron para evaluar los parámetros metabolicos. El grupo SG mostró un mayor consumo de alimento, mayor proporción de ganancia de peso corporal, niveles de glucosa y colesterol que el grupo CG. No se encontraron diferencias significativas en los niveles de triglicéridos e insulina. Respecto al análisis predictivo (semanas 14-20), se mantiene un incremento significativo en el consumo de alimento y se observa una tendencia de aumento en la proporción de ganancia de peso corporal. Esto indica que el consumo de stevia en ratas hembras parece no tener los mismos efectos benéficos reportados en machos. Consumption of stevia has been promoted due to its low caloric intake, it’s effects as anti-diabetic and anti-hypercholesterolemic. However, the effects of stevia consumption is apparently not the same in females than males. The purpose of this study was to evaluate the effect of stevia intake on meal consumption, body weight and levels of glucose, insulin, cholesterol and triglycerides in female Wistar rats during 13 weeks and develop a predictive analysis of the body weight and meal intake over 20 weeks. 20 adult female rats were utilized, these were divided into two groups: control (CG) and stevia (SG), both groups received free access to water and food, the SG also received a stevia solution at 0.2%. Consumption of food, water and stevia solution was recorded daily, while weight was recorded weekly. At the end of the 13 weeks of experiment, the subjects were sacrificed to evaluate the metabolic parameters. The SG group showed a higher consumption of food, higher proportion of body weight gain, glucose levels and cholesterol than the CG. No significant differences were found in levels of triglyceride or insulin. Respect to the predictive analysis (weeks 14-20), a significant increase in food consumption is maintained and an increasing trend is observed in the proportion of body weight gain. This indicates that stevia consumption appears not to have the same benefit effects in female rats than male rats.


1957 ◽  
Vol 35 (12) ◽  
pp. 1113-1118 ◽  
Author(s):  
George H. Beaton ◽  
Hannah Z. Banky ◽  
Audrey M. Haufschild

Doses of growth hormone which were minimal with respect to body weight increase were sufficient to produce significant alterations in liver alanine – glutamic transaminase and arginase activities and blood urea and amino nitrogen levels. The biochemical effects of the hormone appeared coincident with the body weight increase. Female rats showed a more pronounced response to growth hormone than did male rats. This sex difference was evident with respect to all of the metabolic alterations observed. Although it is not possible to state whether the metabolic alterations are direct effects of the hormone, they do take an integral part in bringing about the over-all biological effect.


2021 ◽  
Vol 10 (2) ◽  
pp. 89-97
Author(s):  
EL Lappa ◽  
◽  
C Bogning Zangueu ◽  
EL Nguemfo ◽  
JJ Kojom Wanche ◽  
...  

Ficus vogelii is a medicinal plant mainly found in tropical Africa and reported to treat inflammatory complaints. This study aims to evaluate the acute and sub-chronic toxicity of the aqueous extract of Ficus vogelii stem bark in wistar rats. For acute study, aqueous extract at a single dose of 5000 mg/kg body weight was administered to female rats and observed for 14 days. In the sub-chronic study, the extract was administered daily to both sex rats at the doses of 100, 200, 400, and 600 mg/kg body weight for 28 consecutive days. Body weight was measured weekly, while hematological, biochemical, and histopathological parameters were analyzed after euthanize. Aqueous extract of Ficus vogelii at all tested doses didn’t produced any mortality or significant change on the body weight and relative weight of rats on acute and sub-chronic studies. The lethal dose 50 was estimated greater than 5000 mg/kg (DL50˃5000 mg/kg). Hematological parameters were recorded non-significant in all treated rats. Aqueous extract at 600 mg/kg significantly changed transaminases and alkaline phosphatase activities, these changes were reversible in satellites. The concentrations of bilirubin was increased at 200 and 600 mg/kg in male rats, at 100, 400 mg/kg in female rats. The levels of lipids markers didn’t changed, except the significant decrease of LDL-cholesterol. Histological examination didn’t showed any change in the architecture of the liver and kidney of rats treated compared to control. Thus aqueous extract of Ficus vogelii stem bark didn’t produced adverse effects in rats after oral acute and sub-chronic treatment.


2013 ◽  
Vol 32 (2) ◽  
pp. 113-122 ◽  
Author(s):  
John T. Houpt ◽  
Glenn J. Leach ◽  
Larry R. Williams ◽  
Mark S. Johnson ◽  
Gunda Reddy

4-Amino-2-nitrotoluene (4A2NT; CAS 119-32-4) is a degradation product of 2,4-dinitrotoluene. The toxicity data on 4A2NT are limited. Therefore, we collected toxicity data from rats to assess environmental and human health effects from exposures. The approximate lethal dose for both sexes was 5000 mg/kg. A 14-day toxicity study in rats was conducted with 4A2NT in the feed at concentrations of 0, 125, 250, 500, 1000, and 2000 ppm. Based on a 14-day oral dose range toxicity study with 4A2NT in the feed, 2000 ppm was selected as highest concentration for a subsequent 90-day study. An oral 90-day subchronic toxicity study in rats was conducted with concentrations of 0, 500, 1000, or 2000 ppm of 4A2NT in the feed. The calculated consumed doses of 4A2NT in the feed were 0, 27, 52, or 115 mg/kg/d for males and 0, 32, 65, or 138 mg/kg/d for females. A no-observed adverse effect level could not be determined. The lowest observed adverse effect level was 27 mg/kg/d for males and 32 mg/kg/d for female rats based upon decreased body weight gain. The decreased body weight gain in male rats was the most sensitive adverse event observed in this study and was used to derive a benchmark dose (BMD). A BMD of 23.1 mg/kg/d and BMD with 10% effect level of 15.5 mg/kg/d were calculated for male rats, which were used to derive an oral reference dose (RfD). The human RfD of 1.26 μg/kg/d was derived using current United States Environmental Protection Agency guidelines.


1993 ◽  
Vol 264 (6) ◽  
pp. E986-E992 ◽  
Author(s):  
J. C. Byatt ◽  
N. R. Staten ◽  
W. J. Salsgiver ◽  
J. G. Kostelc ◽  
R. J. Collier

Recombinant bovine prolactin (rbPRL) or bovine growth hormone (rbGH) was administered to mature female rats (10/treatment group) by daily subcutaneous injection for 10 days. Doses ranged from 7 to 5,000 micrograms/day (0.03-24 mg/kg body wt). Both rbPRL and rbGH increased body weight gain and food intake, but these parameters were increased at lower doses of rbPRL (7-63 micrograms/day) than rbGH (> 190 micrograms/day). Weight gain and food intake were maximally stimulated by 190 micrograms/day rbPRL, whereas maximal increased weight gain was obtained with the highest dose of rbGH (5,000 micrograms/day). Total carcass protein was increased by both hormones; however, protein as a percentage of body weight was unchanged. Similarly, neither rbPRL nor rbGH changed the percentage of carcass moisture. Percentage of body fat was increased by rbPRL but was decreased by rbGH. Weight of the gastrointestinal tract and kidneys was increased by both hormones, but increases were in proportion to body weight gain. These data confirm that ungulate prolactin is a hyperphagic agent in the female rat. In addition, they suggest that, while prolactin stimulates growth in mature female rats, this growth is probably not via a somatogenic mechanism.


2007 ◽  
Vol 293 (3) ◽  
pp. R1056-R1062 ◽  
Author(s):  
Jacqueline Férézou-Viala ◽  
Anne-France Roy ◽  
Colette Sérougne ◽  
Daniel Gripois ◽  
Michel Parquet ◽  
...  

Epidemiological and animal studies suggest that the alteration of hormonal and metabolic environment during fetal and neonatal development can contribute to development of metabolic syndrome in adulthood. In this paper, we investigated the impact of maternal high-fat (HF) diet on hypothalamic leptin sensitivity and body weight gain of offspring. Adult Wistar female rats received a HF or a control normal-fat (C) diet for 6 wk before gestation until the end of the suckling period. After weaning, pups received either C or HF diet during 6 wk. Body weight gain and metabolic and endocrine parameters were measured in the eight groups of rats formed according to a postweaning diet, maternal diet, and gender. To evaluate hypothalamic leptin sensitivity in each group, STAT-3 phosphorylation was measured in response to leptin or saline intraperitoneal bolus. Pups exhibited similar body weights at birth, but at weaning, those born to HF dams weighed significantly less (−12%) than those born to C dams. When given the HF diet, males and females born to HF dams exhibited smaller body weight and feed efficiency than those born to C dams, suggesting increased energy expenditure programmed by the maternal HF diet. Thus, maternal HF feeding could be protective against adverse effects of the HF diet as observed in male offspring of control dams: overweight (+17%) with hyperleptinemia and hyperinsulinemia. Furthermore, offspring of HF dams fed either C or HF diet exhibited an alteration in hypothalamic leptin-dependent STAT-3 phosphorylation. We conclude that maternal high-fat diet programs a hypothalamic leptin resistance in offspring, which, however, fails to increase the body weight gain until adulthood.


1993 ◽  
Vol 294 (1) ◽  
pp. 159-165 ◽  
Author(s):  
P K Srivastava ◽  
D J Waxman

The sex-dependent expression and growth hormone (GH) regulation of rat liver glutathione S-transferase (GST) was examined using oligonucleotide probes that distinguish between closely related class Alpha (Ya1, Ya2, Yc) and class Mu (Yb1, Yb2, Yb3) GST mRNAs [Waxman, Sundseth, Srivastava and Lapenson (1992) Cancer Res. 52, 5797-5802]. Northern-blot analysis revealed that the steady-state levels of GST Ya1, Yb1 and Yb2 mRNAs are 2.5-3-fold higher in male as compared with female rat liver. In contrast, GST Yc and Ya2 mRNAs were expressed at a 2-3-fold higher level in female rat liver. Microsomal GST mRNA did not exhibit significant sex-dependent differences in rat liver. Treatment of male rats with GH by continuous infusion suppressed expression of the male-dominant GST Ya1, Yb1 and Yb2 mRNAs to levels at or below those found in female rat liver. This suppressive effect of GH was liver-specific, insofar as GH treatment did not alter kidney GST Ya1 mRNA levels. Hypophysectomy increased expression of the male-dominant GSTs, particularly in female rats (e.g. 8-fold elevation of GST Ya1 mRNA). GST Yc mRNA was increased approx. 2-fold in hypophysectomized males, indicating that this mRNA is subject to negative regulation by one or more pituitary-dependent factors. Continuous GH treatment of the hypophysectomized rats suppressed the expression of mRNA of GSTs Ya1, Yb1 and Yb2 when given as a continuous infusion, but not when given by an intermittent (twice daily) GH-injection schedule. Combination of continuous exposure to GH with thyroxine treatment resulted in a more complete suppression of GSTs Ya1, Yb1 and Yb2. In contrast, thyroxine increased the expression of GST Yc in hypophysectomized rats. These studies establish that several Alpha and Mu class GSTs are expressed in a sex-dependent fashion in adult rat liver, where they are regulated by multiple pituitary-dependent hormones through pretranslational mechanisms.


1966 ◽  
Vol 51 (2) ◽  
pp. 315-320 ◽  
Author(s):  
C. M. Goodall ◽  
J. B. Gavin

ABSTRACT Male rats were hypophysectomized at four weeks of age, rested for four weeks, and then were fed a thyroid digest in their drinking water continuously for up to seventy weeks. The digest treatment supplied the equivalent of 1.25μg L-thyroxine per 100 g rat per day approximately. From the body weight curves and radiographic measurements of the skull and mandibles, it was shown that contrary to some previous reports in the literature there was no statistically significant change in the indices of growth or body mass when compared with controls receiving no thyroid treatment. It is suggested that data previously reported by others, indicating a stimulation of growth in hypophysectomized rats by thyroid hormones, may have been derived from animals having minute but still effective pituitary remnants, and somewhat more stringent morphological criteria of hypophysectomy are proposed.


2016 ◽  
Vol 36 (5) ◽  
pp. 483-493 ◽  
Author(s):  
AO Abolaji ◽  
IO Awogbindin ◽  
IA Adedara ◽  
EO Farombi

The fungicide carbendazim (CBZ) and insecticide chlorpyrifos (CPF) are currently applied together by farmers for the control of pests. Here, we investigated the impacts of 7 days oral co-exposure to 10 mg/kg body weight of CPF and 50 mg/kg body weight of CBZ on selected oxidative stress and antioxidant biomarkers in the liver, kidney, and spleen of female rats. The results showed that while the body weight gain and relative organ weights were not significantly affected after separate exposure to CPF and CBZ, there was a significant decrease in the body weight gain with concomitant increases in the relative kidney and spleen weights of rats treated with the mixture. Also, CPF and CBZ co-exposure significantly increased the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine ( p < 0.05) when compared with the groups treated with CBZ or CPF alone and the control. The significant decreases in both antioxidant enzymes activities and nonenzymatic antioxidant level following individual administration of CPF and CBZ to rats were intensified in the co-exposure group ( p < 0.05). Additionally, the marked increases in the levels of oxidative stress indices in liver, kidney, and spleen of rats treated with CPF or CBZ alone were intensified in the co-exposure group ( p < 0.05). Histopathologically, co-exposure to CPF and CBZ exacerbates their individual effects on the liver, kidney, and spleen. These findings showed that co-exposure to CPF and CBZ in rats elicited more severe oxidative damage on the liver, kidney, and spleen of the rats, indicative of an additive effect compared to CPF or CBZ alone and as such, may pose a greater environmental risk to humans.


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