In a post Peggy mentioned reading an article at WSJ, describing diabetes seemed went away after intestine surgery (anecdote, she said); that led me to mention the relationship between intestine and diabetes.
In the beginning an endocrine organ is defined as the one secreting hormone, such as thyroid and adrenal gland. But things got more complicated as more hormones discovered that are secreted by the organs not characterized as endocrine organs.
Intestine (gastrointestinal system) secretes incretin that regulates blood glucose (sugar); kidney produces erythropoietin, a hormone that stimulates bone marrow to make red blood cells. Amgen Pharmaceuticals made a fortune by making recombinant erythropoietin (Epogen or Procrit) and emerged as the first biotech company to become a pharmaceutical giant.
Seizure results from synchronous (occurring at the same time) firing of cortical neurons; they’re not supposed to do that! Brain cells (neurons) are complex and sophisticated; firing at the same time would be too boring and simplistic; that led a professor in neuro science to say, “We leave synchrony to the heart, that pathetically simple little organ.” (I read this in Joy’s lecture notes some years ago.)
To prove it is not just a simple mechanic pump, heart also secretes various hormones; the ventricle (lower chamber) secretes B-type natriuretic peptide or used to call brain natriuretic peptide (BNP—the name stuck) whereas the atrium (upper chamber) secretes atrial natriuretic peptide. These hormones act like a diuretic (one to promote diuresis—making more urine to get rid of excessive water in the body). This ingenious God-design can be treated like a “self-help”, i.e. when the atrium and ventricle are stretched because of too much volume; these peptides (hormones) are produced to get rid of the excessive amount of fluid.
This post was inspired by the intestine transplant done by Dr. Yun Chen (陳芸) in Taiwan, so I would also mention the enteric nervous system (part of autonomous nervous system) which is dubbed as the “second brain” or "the brain in the gut". The intestine does listen to the commands of the brain (the ‘real’ one) through its extrinsic nervous system, but it has its own barin, thus own will; it can function independent of the brain. I am always curious about how this “second brain” functions after intestine transplant, about which I know nothing.
(photo credit to UpToDate: a case of intestine pseudo-obstruction in a patient with scleroderma showing dilated duodenum and jejunum)
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