Epidermal Growth Factor Treatment Induces D2 Dopamine Receptors Functionally Coupled to Delayed Outward Potassium Current (lK) in GH4C1 Clonal Anterior Pituitary Cells

1994 ◽  
Vol 59 (1) ◽  
pp. 10-19 ◽  
Author(s):  
Robert Gardette ◽  
Ramahaferizo Rasolonjanahary ◽  
Claude Kordon ◽  
Alain Enjalbert
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Anterior Pituitary ◽  
Potassium Current ◽  
Pituitary Cells ◽  
D2 Dopamine Receptors ◽  
Epidermal Growth Factor Treatment ◽  
Epidermal Growth ◽  
Outward Potassium Current ◽  
Growth Factor Treatment

Lack of effect of epidermal growth factor treatment in late-pregnant ewes on subsequent lactation

1991 ◽  
Vol 58 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Christine B. Gow ◽  
Debbi J. Singleton ◽  
Mervyn J. Silvapulle ◽  
G. Philip M. Moore
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Mammary Gland Development ◽  
Epidermal Growth Factor Treatment ◽  
Epidermal Growth ◽  
And Function ◽  
And Control ◽  
Gland Development ◽  
Mean Concentration ◽  
Growth Factor Treatment

SummaryTwin-bearing ewes were treated with epidermal growth factor (EGF) to determine its effect on mammogenesis and resultant milk production and composition. The EGF was infused intravenously at a dose rate of O5 mg/d in 300 ml saline between days 117 and 139 of gestation; control animals received placebo infusions of saline. All animals then received continuous infusions of 300 ml/d saline on days 139–144. Following parturition 1–5 d later, ewes were milked by hand for 10 d and thereafter were machine-milked until day 16 of lactation. At this level of treatment, EGF was not detected in the circulation during infusion and feed intake was not affected. All ewes gave birth to healthy twin lambs. There were no effects of EGF on birth weights of lambs, live weights of ewes or lengths of gestation. An EGF immunoreactive material was detected in the mammary secretions of control ewes at a mean concentration of 2 μg/l on day 1 of lactation. Two ewes had detectable levels on day 2, but none was found in the milk thereafter. In the EGF-infused group, concentrations of EGF in colostrum were ñ 10 times higher than in the control ewes on day 1 of lactation and EGF was detected in mammary secretions on day 2 but not in subsequent milk samples. A range of 0·3–0·5% of the EGF infused appeared in mammary secretions over the first 2 d of lactation. No other differences were observed for colostrum composition, subsequent milk yield or composition between the two groups of ewes indicating that mammary gland development and function were unaffected. The levels of EGF observed in the mammary secretions of treated and control ewes indicate that the mammary glands accumulate and store EGF in the pre partum period.

Identification of epidermal growth factor-secreting cells in the anterior pituitary of lactating female rats

1996 ◽  
Vol 148 (2) ◽  
pp. 319-324 ◽  
Author(s):  
A Mouihate ◽  
D Verrier ◽  
J Lestage
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Anterior Pituitary ◽  
Plaque Assay ◽  
Female Rats ◽  
Pituitary Cells ◽  
Cellular Origin ◽  
Anterior Pituitary Cells ◽  
Epidermal Growth ◽  
Reverse Haemolytic Plaque Assay

Abstract Epidermal growth factor (EGF) is synthesized and secreted by mammalian anterior pituitary cells. It stimulates GH and prolactin (PRL) secretion, but the cellular origin of EGF is relatively unexplored. The objective of this study was to characterize the cells that secrete EGF in the anterior pituitary of lactating rats. An EGF reverse haemolytic plaque assay (RHPA) was used to identify EGF-secreting cells and this RHPA was combined with immunofluorescence using antibodies to the six major adenohypophysial hormones (i.e. PRL, GH, LH, FSH, TSH and ACTH). Approximately 20% (20·33 ± 2·96%) of the cells in the pituitary of lactating rats secrete EGF. The EGF-secreting cell population was composed of the following labelled cells: PRL (27%), GH (20%), LH (18%), FSH (14%), TSH (14%) and ACTH (5%). The present study showed that EGF is released by a subpopulation of anterior pituitary cells composed of all the classic hormone-containing cells. Journal of Endocrinology (1996) 148, 319–324

Effects of epidermal growth factor and glutamine-supplemented parenteral nutrition on the small bowel of septic rats

1992 ◽  
Vol 82 (5) ◽  
pp. 573-580 ◽  
Author(s):  
M. Salleh ◽  
M. Ardawi
Keyword(s):  
Growth Factor ◽  
Small Bowel ◽  
Epidermal Growth Factor ◽  
Parenteral Nutrition ◽  
Nitrogen Balance ◽  
Glutamine Supplementation ◽  
Epidermal Growth Factor Treatment ◽  
Epidermal Growth ◽  
Growth Factor Treatment

1. The effects of parenteral nutrition with or without glutamine supplementation and epidermal growth factor treatment (0.15 μg/g body weight) was studied in the small bowel of septic rats after 4 days. 2. Septic rats infused with glutamine-supplemented parenteral nutrition with or without epidermal growth factor treatment survived sepsis significantly better than other septic rats given parenteral nutrition. The cumulative percentage of deaths over 4 days in septic rats infused with glutamine-supplemented parenteral nutrition was 20% (without epidermal growth factor) and 15% (with epidermal growth factor) compared with 50% in septic rats treated with parenteral nutrition without glutamine and 35% in septic rats given parenteral nutrition without glutamine but with epidermal growth factor treatment. 3. Glutamine-supplemented parenteral nutrition with or without epidermal growth factor treatment resulted in improved nitrogen balance in septic rats. The cumulative nitrogen balance over the 4 day period was the least negative as compared with other groups of septic rats. 4. Septic rats given parenteral nutrition with glutamine, epidermal growth factor or glutamine and epidermal growth factor exhibited marked increases in intestinal net rates of utilization of glutamine (P < 0.001) and production of ammonia (P < 0.001) compared with septic rats given parenteral nutrition without glutamine and/or epidermal growth factor treatment. 5. Septic rats given parenteral nutrition with glutamine, epidermal growth factor or glutamine and epidermal growth factor exhibited significant increases in jejunal wet weight (by 32.4–40.6%), DNA content (by 24.2–34.7%), protein content (by 29.1–50.0%), villus height (by 16.3–26.4%) and crypt depth (by 20.3–29.6%) compared with other groups of septic rats. 6. The rate of intestinal [3H]thymidine incorporation in vivo and thymidine kinase activity in vitro were significantly increased (P < 0.001) in septic rats given parenteral nutrition with glutamine, epidermal growth factor or glutamine and epidermal growth factor. 7. The activity of jejunal glutamine synthetase was lower (by 66.3–90.0%) in septic rats treated with glutamine, epidermal growth factor or glutamine and epidermal growth factor, whereas glutaminase activity was increased (by 28.1–31.0%) in response to parenteral nutrition supplemented with glutamine only. 8. It is concluded that the administration of glutamine-supplemented parenteral nutrition, with or without epidermal growth factor, is beneficial to the small bowel of septic rats.

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