Endocrine system gonads, have secondary endocrine functions. For example, the kidney secretes endocrine hormones such as erythropoietin and renin. Hormones can consist of either amino acid complexes, steroids, eicosanoids, leukotrienes, or prostaglandins. The endocrine system is in contrast to the exocrine system, which secretes its hormones to the outside of the body using ducts. As opposed to endocrine factors that travel considerably longer distances via the circulatory system, other signaling molecules, such as paracrine factors involved in paracrine signalling diffuse over a relatively short distance. The word "endocrine" derives via New Latin from the Greek words , "endon", "inside, within," and ,
Multiple endocrine neoplasia all but abandoned in the medical literature. Another early report was Schimke "et al." in 1968. OMIM also includes a fourth form of multiple endocrine neoplasia ("MEN4"), associated with CDKN1B. The presentation is believed to overlap that of MEN1 and MEN2. The "MEN1" gene consists of ten exons, spanning about 10 kb, and encodes a 610 amino acid protein named menin. The first exon and the last part of exon 10 are not translated. A main transcript of 2.8 kb has been described in a large variety of human tissues (pancreas, thymus, adrenal glands, thyroid, testis, leukocytes, heart, brain, lung,