Monday, January 28, 2013

Hormone Research: Somatostatin

Somatostatin

Somatostatin is also recognized as growth hormone-inhibiting hormone or somatotropin release-inhibiting hormone. Despite the different titles, somatostatin is a peptide hormone that controls the endocrine system and affects neurotransmission and the spreading of cells with somatostatin receptors and inhibition of the many secondary hormones. Somatostatin is categorized as an inhibitory hormone, whose actions are spread to various parts of the body such as the anterior pituitary gland and the gastrointestinal system. Somatostatin is produced by neuroendocrine neurons of the hypothalamus and these neurons arranges to the median eminence where somatostatin is released into the hypothalamo-hypophysial system. It is then carried to the anterior pituitary gland, where it inhibits the secretion of growth hormone. Somatostatin has two active forms, one of fourteen amino acids and the other of twenty-eight amino acids. Humans only have one somatostatin gene (SST) while vertebrates (animal with backbone) have six different somatostatin genes (SS1-6). Somatostatin secretes in numerous locations in different organs of the body. In the digestive system, it secretes in the stomach, intestine, and the delta cells of the pancreas.

Video:

References: http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/otherendo/somatostatin.html

http://www.yourhormones.info/hormones/somatostatin.aspx
http://www.youtube.com/watch?v=artQTDaWXQ8

Sunday, January 27, 2013

Endocrine Disruptor: Methoxychlor

Methoxychlor

Methoxychlor is used as an insecticide effective against pests. There’s a wide range of uses of methoxychlor, from being used on field crops to killing parasites. However, all pesticide use of methoxychlor was suspended in 2000. According to oral study in animals, the exposure of methoxychlor resulted in effects to the liver, kidneys, and nervous system. Moreover, the reproductive and developmental effects are the major concern of methoxychlor. Developmental and reproductive effects include abortions, reduced fertility, reduced litter size, and skeletal effects. The exposure to methoxychlor would most likely be from inhalation or dermal contact by workers involved in the manufacture, handling, or application of methoxychlor. Humans could be exposed to methoxychlor at home by ingesting food or water contaminated with methoxychlor. EPA has low confidence in the dangerous study of methoxychlor because no inferences could be made to the maternal or developmental toxicity of methoxychlor due to the low sureness in the database because of the lack of definitive chronic toxicity. EPA has classified methoxychlor as a Group D, because human data are unavailable and animal evidence is indecisive.