The submandibular lymph nodes (submaxillary glands in older texts) are lymph nodes beneath the body of the mandible in the submandibular triangle, and rest on the superficial surface of the submandibular gland.
One gland, the middle gland of Stahr, which lies on the facial artery as it turns over the mandible, is the most constant of the series; small lymph glands are sometimes found on the deep surface of the submandibular gland.
The afferents of the submandibular glands drain the medial canthus, the cheek, the side of the nose, the upper lip, the lateral part of the lower lip, the gums, and the anterior part of the margin of the tongue.
Efferent lymph vessels from the facial and submental lymph nodes also enter the submandibular glands. Their efferent vessels pass to the superior deep cervical lymph nodes.
Insulin-like growth factor 1 (IGF-1) , also called somatomedin C, is a hormone similar in molecular structure to insulin which plays an important role in childhood growth, and has anabolic effects in adults. IGF-1 is a protein that in humans is encoded by the IGF1 gene. IGF-1 consists of 70 amino acids in a single chain with three intramolecular disulfide bridges. IGF-1 has a molecular weight of 7,649 Daltons. In dogs, an ancient mutation in IGF1 is the primary cause of the toy phenotype. IGF-1 is produced primarily by the liver. Production is stimulated by growth hormone (GH). Most of IGF-1 is bound to one of 6 binding proteins (IGF-BP). IGFBP-1 is regulated by insulin. IGF-1 is produced throughout life; the highest rates of IGF-1 production occur during the pubertal growth spurt. The lowest levels occur in infancy and old age. A synthetic analog of IGF-1, mecasermin, is used in children for the treatment of growth failure.