Ontogenesis of epidermal growth factor in liver of BALB mice

1988 ◽  
Vol 255 (1) ◽  
pp. E28-E32
Author(s):  
N. P. Laborde ◽  
M. Grodin ◽  
G. Buenaflor ◽  
P. Brown ◽  
D. A. Fisher

To characterize the ontogenesis of hepatic epidermal growth factor (EGF) metabolism in normal BALB mice, we measured serum and liver concentrations of EGF and liver concentrations of pre-pro EGF mRNA. Female and male animals were studied at 1, 2, 5, 7, and 10 wk of life. After death, body weight and length were measured, and serum and liver tissues were collected for EGF determinations. Immunoreactive serum EGF (means +/- SE) increased at 7 and 10 wk and was significantly higher (P less than 0.05) in males (465 +/- 58 and 683 +/- 120 pg/ml) than females (188 +/- 52 and 295 +/- 64 pg/ml). Liver EGF concentrations were low at 1, 2, and 5 wk, significantly increasing (P less than 0.01) at 10 wk to 179 +/- 36 vs. 268 +/- 49 pg/mg protein for females and males, respectively (female and male values were significantly different, P less than 0.01). Pre-pro EGF mRNA was examined at 1, 2, 3, 5, 7 and 10 wk. EGF message increased in liver to highest values at 10 wk in both males and females. There was a high correlation between serum and liver EGF concentrations during the first 10 wk (r = 0.97 and 0.85 for males and females, respectively) and a twofold increase in liver EGF mRNA between 3 and 10 wk of postnatal life. These results suggest that liver may be an important source of circulating EGF in developing BALB mice.

1985 ◽  
Vol 105 (2) ◽  
pp. 197-200 ◽  
Author(s):  
M. Hiramatsu ◽  
M. Kashimata ◽  
N. Minami ◽  
N. Minami ◽  
M. Kumegawa

ABSTRACT Epidermal growth factor (EGF), administered subcutaneously to neonatal mice at daily doses of 1, 2 and 4 μg/g body weight for 3 days, significantly increased glucosamine-6-phosphate synthetase activity in the colon. A single injection of EGF at doses of 2 and 4 μg/g body weight also significantly increased enzyme activity. When administered to mature mice, EGF (4 μg/g body weight for 3 days) had no apparent effect on the enzyme activity. From these results, we suggest that EGF acts as a trophic factor for the maturation of the colonic mucosa of neonatal mice. J. Endocr. (1985) 105, 197–200


1990 ◽  
Vol 41 (6) ◽  
pp. 1147 ◽  
Author(s):  
BW Brown ◽  
PE Mattner ◽  
BA Panaretto ◽  
GH Brown ◽  
BD Gream ◽  
...  

Seminal characteristics and flock fertility were studied in Merino rams treated with mouse epidermal growth factor (EGF). Intravenous infusions of 105 8g EGF/kg body weight over 24 h in five rams had no statistically significant effect on daily sperm production measured from 6-10 weeks after dosing or on the percentages of spermatozoa that were unstained (nigrosinleosin stain) or morphologically normal. At 7-8 weeks post treatment, the percentage of spermatozoa exhibiting progressive motility was significantly reduced (P<0.05). By 9-10 weeks after treatment, the seminal characteristics were normal in all rams. In 1987, eight rams and in 1988, six ofthe same rams, were joined with ewes for 6 weeks (at a rate of 2%) 12 weeks after s.c. injection of 150 8g/kg body weight. Compared with the performance of control rams, EGF had no significant effect on ram fertility, nor did it produce any teratogenic effects in their progeny or effect their survival rate.


1994 ◽  
Vol 45 (2) ◽  
pp. 333 ◽  
Author(s):  
BW Brown ◽  
PR Stockwell ◽  
BA Panaretto

In the present study on Merino ewes, murine epidermal growth factor (mEGF) and genetically engineered methionine epidermal growth factor (met-EGF), given at depilatory dose rates (120 8g mEGF/kg body weight (n = 82) and 250 8g met-EGF/kg body weight (n = 100) respectively), were assessed for effects on fertility, pregnancy rate and lambing performance. Following EGF injection, the ewes were fitted with a net retention system to hold the fleece on the animals for 5 weeks, at the end of which time the wool was harvested from the EGF-treated ewes by hand and was shorn conventionally from non EGF-treated controls (n = 100). All ewes were then joined to raddled-harnessed entire rams (2%) for 6 weeks. The dates of raddle markings recorded during the teaser period and during joining to entire rams revealed that the majority (97%) of control ewes were in oestrus at expected times during the joining period, whilst significantly (P < 0.001) fewer ewes in the mEGF (75%) and the met-EGF (65%) treated groups exhibited oestrus at the expected time. The majority of the ewes that were delayed in onset of oestrus were at the mid to late luteal stages of the oestrous cycle at the time of EGF treatment. There was no material difference between the three groups in the number of ewes returning to service during the joining period, or in the number of empty ewes. The three groups were also similar in the proportions of ewes bearing single or twin lambs, in the overall lambing percentage (controls 108010, mEGF 109%, et-EGF 107%) and survival of lambs to weaning. No abnormalities were found in any of the lambs. It appears that an interval of 5 weeks between dosing and joining is sufficient time for EGF-treated ewes to resume normal cyclicity and fertility.


1991 ◽  
Vol 42 (8) ◽  
pp. 1301
Author(s):  
IG Hazelton ◽  
BA Panaretto ◽  
PR Stockwell ◽  
JT Marshall ◽  
CD Nancarrow

Pregnant Merino ewes were treated with 90 8g murine epidermal growth factor (EGF) per kg body weight at either 25 (n = 80), 50 (n= 40) or 75 (n =40) days of gestation. Untreated control ewes were included at each gestational age (n=20, 12 and 12 respectively). Fifteen and twenty per cent of the ewes treated with EGF at days 25 and 50 respectively failed to lamb, significantly more (P < 0.01 ) than in ewes treated at day 75, where only one ewe failed to lamb, and in control ewes which all lambed. These differences were not reflected in significant differences between the overall percentage of lambs born in each group, as the incidence of abortion in single-bearing ewes was higher than in ewes carrying multiple fetuses. All lambs born alive to EGF-treated ewes appeared normal. Plasma progesterone concentrations measured before treatment and at 8, 24 and 48 h after EGF injection fell significantly in treated ewes relative to controls (P<0.01 at day 25; P<0.05 at days 50 and 75) and concentrations were lowest at 8 and 24 h after injection in those ewes which aborted. Following EGF treatment at days 25 and 50 of gestation, abortion occurred in all ewes with very low plasma progesterone concentrations 8 to 48 h after EGF injection, probably as a result of EGF-induced luteolysis. In other ewes plasma progesterone concentrations returned to pretreatment values by 48 h, indicating incomplete luteolysis. The delayed abortion observed in some of these ewes further suggests that other mechanisms of action are involved in EGF-induced abortion.


1982 ◽  
Vol 94 (2) ◽  
pp. 191-202 ◽  
Author(s):  
B. A. Panaretto ◽  
G. P. M. Moore ◽  
D. M. Robertson

Twenty-four adult Merino wethers were given mouse epidermal growth factor (mEGF) subcutaneously at doses ranging from 0·02 to 0·12 mg/kg body weight or intravenously in the dose range 010 to 0·14 mg/kg body weight for periods ranging from 3 to 48 h. Plasma concentrations of mEGF were measured by radioimmunoassay and effects of treatment on food consumption and wool growth were observed. Plasma concentrations of the protein sustained for 15–24 h at about 20 ng mEGF/ml (or exceeding this) almost invariably caused feed rejection and casting of the fleeces. This last result clearly indicated disruption of proliferative activity among the replicating cells in wool follicles which regulate wool growth. The inhibitory effects on appetite and wool growth of smaller doses of the protein and of plasma concentrations equal to those above which were sustained for shorter periods have also been examined. Approximately 10% of the dose of mEGF appeared in the urine of three sheep 1 to 3 days after the start of s.c. infusions of 5 mg for 7 h.


1995 ◽  
Vol 146 (3) ◽  
pp. 381-393 ◽  
Author(s):  
H Adachi ◽  
H Kurachi ◽  
H Homma ◽  
K Adachi ◽  
T Imai ◽  
...  

Abstract Aged mice exhibit an increase in their body weight (BW), which is associated with fat deposit increase. Epidermal growth factor (EGF) concentration in the submandibular gland also increases with aging. We examined the effects of elevated EGF on the adiposity of aged female mice. Studies were started in two groups of animals consisting of sham-operated (n=10) and sialoadenectomized (n=10, Sx; surgical removal of the submandibular glands) mice at 8 weeks of age. Body weight gain and food intake were measured throughout 78 weeks of age in these two groups. Body weight was significantly less in the Sx group throughout 78 weeks, while food intake was not changed by Sx after 12 weeks of age. To examine further if EGF plays a role in the induction of adiposity in aged female mice, sham-operated animals were given 100 μl anti-EGF rabbit antiserum (anti-EGF group, n=5) or normal rabbit serum (control group, n=5) every 3 days, and Sx animals were given 5 μg/day EGF (Sx+EGF group, n=5) or saline (Sx group, n=5) from 78 weeks of age for 3 weeks. At 81 weeks of age, all animals of these four groups were killed, and carcass fat deposition and fat cell sizes were measured. Although the relative weights (weight ratio to BW) of the liver and kidney were not changed by Sx and anti-EGF treatment, the relative weights of mesenteric and subcutaneous fat tissues and adipocyte weights were significantly decreased in Sx and anti-EGF groups compared with the control group. Moreover, both acyl-CoA synthetase (ACS) and lipoprotein lipase (LPL) mRNA levels were significantly decreased by Sx or anti-EGF administration in mesenteric and subcutaneous fat tissues. On the other hand, EGF administration to Sx animals had no effect on BW, fat tissues and adipocyte weights, and ACS and LPL mRNA levels. The results, however, were consistent with the fact that adipose tissue EGF receptors were down regulated in Sx mice. These findings suggest that EGF may play a role in the induction of adiposity in aged female mice. Journal of Endocrinology (1995) 146, 381–393


1988 ◽  
Vol 41 (4) ◽  
pp. 463 ◽  
Author(s):  
Anne J Campbell ◽  
S S Adams ◽  
Mary W Davey ◽  
DA Titchen

Lys-�-urogastrone, an analogue of human {1-urogastrone with an additional N-terminal lysine, was shown to have similar effects in mice and sheep to mouse epidermal growth factor (mEGF). Lys-{1- urogastrone in doses of 0'18-3 �24 "g g-I body weight caused both precocious separation of eyelids and eruption of incisors in neonatal mice.


2021 ◽  
Vol 20 (3) ◽  
pp. 25-33
Author(s):  
E.S. Pashinskaya ◽  

Objectives. To study the effect of toxoplasmas on the changes in the expression of protooncogenes BIRC5, ERBB-2/HER2-NEU, GLI, VEGF and the anti-oncogene TP53 in rats in an experiment depending on the infection dose and the period of parasite development. Material and methods.The experiment was conducted on female Wistar rats to determine changes in the expression of the protooncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI 1, vascular endothelial growth factor (VEGF) and the anti-oncogene TP53 in comparison with the reference genes β-actin (ACTB) and GAPDH by means of PCR analysis in the tissues of 10 healthy and 120 animals invaded at different doses. Statistical comparison of the results of all groups was drawn with the data of the «control» series (healthy animals, biopsies of the lungs, liver, spleen, brain). The results obtained in the experimental groups were as follows: the infection dose of 25 toxoplasma tachyzoites per 1 g of the animal body weight (5000 tachyzoites per female) and the infection dose of 50 toxoplasma tachyzoites per 1 g of the animal body weight (10000 tachyzoites per female), then they were also compared with each other. Statistical processing of the obtained data was carried out using the program Statistica 10.0. The differences were considered to be reliable at a significance level of less than 0.05 (p<0.05). Results. Toxoplasma was found to cause an infection dose-dependent increase in the expression of the protooncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI, vascular endothelial growth factor (VEGF) and a change in the strength expression of the anti-oncogene TP53 at all stages of the parasite development. Conclusions. Experimental toxoplasmosis alters the expression of the protooncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI, vascular endothelial growth factor (VEGF), and the anti-oncogene TP53 in the tissues of the intermediate host.


1991 ◽  
Vol 131 (1) ◽  
pp. 95-100 ◽  
Author(s):  
R. P. Schaudies ◽  
J. Grimes ◽  
D. Davis ◽  
O. Koldovský

ABSTRACT Suckling rats exhibit age-dependent differences in epidermal growth factor (EGF) levels in several organs. The present studies evaluated the effects of two hormones known for their maturative effect on suckling rats, cortisone and tri-iodothyronine (T3), on immunoreactive EGF levels in specific organs. Suckling rats were administered cortisone (5 mg/100 g body weight per day) or T3 (50 μg/100 g body weight per day) on days 8, 9, 10 and 11 after birth, and killed on day 12. Submandibular glands, kidneys, pancreas, liver and gastrointestinal tract mucosa and lumen were assayed for immunoreactive EGF by a speciesspecific radioimmunoassay. Low levels of EGF in the submandibular glands were increased slightly by both T3 and cortisone treatment. Cortisone evoked a tenfold increase in EGF in the pancreas, but had no effect on levels in the kidney or liver. In contrast, T3 evoked a sixfold increase in the EGF level in the kidney, but had no effect on levels in the pancreas or liver. Hormonal administration had no effect on EGF levels in the stomach. Within the intestinal tract, cortisone had no effect on the luminal EGF content of the duodenum, jejunum or ileum, but caused a decrease in the midjejunum. T3 evoked a decrease in the luminal EGF content of the ileum. The effect of cortisone on mucosal EGF content varied between regions; an increase was seen in the duodenum with a decrease in the midjejunum and ileum. T3 administration resulted in a significant decrease in EGF only in the mucosa of the ileum. The EGF-degradative capacity of the luminal contents of the jejunum and ileum, as studied in vitro, were increased by treatment with both T3 and cortisone. However, no direct correlation was observed between alterations of the EGF content in the lumen or mucosa and the increased degradative capacity. We therefore conclude that modulation of EGF levels within the intestine cannot be explained exclusively by alterations in the degradation rates. The results indicate that both adrenal and thyroid glands may play an important role in the modulation of EGF levels in the developing rat. Journal of Endocrinology (1991) 131, 95–100


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