epidermal-growth-factor and Muscular-Dystrophy--Animal

We evaluated the nerve growth factor (NGF) contents in the submaxillary gland of the mdx mouse, a model for Duchenne muscular dystrophy (DMD), and found that the NGF and NGF mRNA contents in this organ, where extraordinarily high amounts of NGF are synthesized and stored independently of development or maintenance of the nervous system, were markedly elevated in the male mdx mouse at 8 and 11 weeks of age. However, the NGF content of this organ in 4-week-old male mdx mice was lower than that of control mice although statistical significance of difference was not observed. In the mdx female mouse, the submaxillary NGF content was significantly lower than that of the normal mouse at 4 weeks of age, but was similar to that of the normal at 8 and 11 weeks of age. The amounts of epidermal growth factor (EGF), another protein that is known to be sexually and developmentally regulated in the mouse submaxillary gland like NGF, was found to be also significantly increased in this organ of the male mdx mouse at 8 and 11 weeks of age, and to be significantly decreased in that of the female mdx mouse at 4 weeks of age. The parallel changes in NGF and EGF contents during development of the submaxillary gland suggest that the mdx mouse suffers from some abnormality in the development of this organ.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aging; Animals; Epidermal Growth Factor; Female; Immunoenzyme Techniques; Male; Mice; Mice, Neurologic Mutants; Muscular Dystrophy, Animal; Nerve Growth Factors; RNA, Messenger; Sex Characteristics; Submandibular Gland; Testosterone; Thyroxine

Topics: Animals; Epidermal Growth Factor; Female; Male; Mice; Mice, Inbred C57BL; Muscles; Muscular Dystrophy, Animal

Topics: Animals; Epidermal Growth Factor; Female; Male; Mice; Mice, Inbred C57BL; Muscles; Muscular Dystrophy, Animal

Topics: Animals; Epidermal Growth Factor; Female; Male; Mice; Microscopy, Electron; Muscular Dystrophy, Animal; Nerve Growth Factors; Sex Factors; Submandibular Gland; Testosterone; Thyroxine; Triiodothyronine

Epidermal growth factor (EGF) has been measured in extracts of submandibular glands from mice with hereditary muscular dystrophy. RIA results show that adult male and female dystrophic mice have significantly less submandibular gland EGF than do unafflicted controls. Despite the differences in gland content of the protein, serum levels of EGF are similar in both dystrophic and control animals. Furthermore, submandibular gland concentrations of amylase are normal in the dystrophic mice, indicating that not all proteins synthesized by the glands are affected. Gel filtration studied reveal that the elution properties of EGF in extracts of glands from dystrophic and control animals are indistinguishable. Unexpectedly, the chromatographic profiles indicate that most of the EGF in gland extracts elutes as a low molecular weight protein when the molecule is studied at low, biologically active concentrations; only a small portion of the protein is associated with a high molecular weight complex. Under the same experimental conditions, submandibular gland nerve growth factor maintains its association with other components in a high molecular weight form.

Topics: Amylases; Animals; Carrier Proteins; Chromatography, Gel; Epidermal Growth Factor; Female; Male; Mice; Molecular Weight; Muscular Dystrophy, Animal; Peptides; Sex Factors; Starvation; Submandibular Gland