Epidermal growth factor in the rat lung.
Journal - Histochemistry (GERMANY )
Epidermal Growth Factor (EGF) in pharmacological doses is able to induce precoccious lung maturation in rabbits and sheeps. As EGF is probably acting in a para- or autocrine way, we have searched for EGF in the lungs. We report EGF immunoreactivity to be present in the type II pneumocytes of the rat from a couple of days prior to birth and throughout life. Further, we report EGF immunoreactivity to be present in cells in the bronchi and the bronchioles from day 20-21 of gestation and throughout life. G-200 gelchromatography of lung extracts indicates that the EGF-reactive material is a high molecular weight form of EGF. Since previous studies have shown that EGF in pharmacological doses is able to promote lung maturation, our results may imply a physiological role for EGF in the lungs.
|ISSN : ||0301-5564|
|Mesh Heading : ||Animals Animals, Newborn Bronchi Epidermal Growth Factor Epithelium Fetus Gestational Age Immunoenzyme Techniques Lung Molecular Weight Pulmonary Alveoli Rats Rats, Inbred Strains chemistry embryology chemistry metabolism embryology chemistry embryology|
|Mesh Heading Relevant : ||analysis chemistry|
Epidermal growth factor reactivity in rat milk.
Journal - Regulatory peptides (NETHERLANDS )
The concentration of EGF immunoreactivity in rat whey increases from 0.3 pmol/ml at lactation day 1 to 2.0 pmol/ml at lactation day 19. The concentration of EGF is not influenced when the rats undergo sialoadenectomy prior to mating. On S-200 gel chromatography, almost all EGF-reactivity in rat whey elutes as a broad peak corresponding to a Stokes radius of 4.0 nm (an approximate molecular weight of 80 kDa). Almost no 6 kDa EGF is present. Judged by gel filtration of whey pre-incubated with 125I-EGF (6 kDa), no binding protein for EGF is present in rat whey. When rat milk is incubated overnight at 37 degrees C, the 80 kDa EGF is degraded and elutes as a peak with a Stokes radius of 2.7 nm, corresponding to a molecular weight of approximately 35 kDa EGF and as a peak corresponding to 6 kDa EGF. Also, after partial purification by immuno-affinity chromatography, the EGF-reactive material in rat whey behaves as a peptide with a Stokes radius of 2.7 nm, corresponding to a molecular weight of approximately 35 kDa at gel filtration. Comparative binding studies between EGF purified from the submandibular glands and the EGF purified from rat whey confirm differences in the binding to antibodies raised against submandibular EGF, but not in binding to the EGF-receptor. Our results make it unlikely that EGF in rat whey is derived from the submandibular glands.
|ISSN : ||0167-0115|
|Mesh Heading : ||Animals Chromatography, Gel Epidermal Growth Factor Female Milk Molecular Weight Pregnancy Rats Rats, Inbred Strains Receptor, Epidermal Growth Factor Submandibular Gland chemistry metabolism metabolism|
|Mesh Heading Relevant : ||metabolism metabolism|