Expert: John Locke - 3/8/2010

Question
So I saw another question on here about removal of the hypothalamus to a young boy and how this would affect his puberty. The expert said that the treatment for this would be GnRH shots, or testosterone.
So my question is, is this an short-term treatment to "kick start" puberty, or a an ongoing treatment? And why. Thanks!

Answer
Thanks for using AllExperts. The hypothalamus is the brain structure responsible for the production of GnRH, which stimulates the anterior pituitary gland to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Those hormones go on, in turn, to stimulate the production of sex steroids (androgens and estrogens) from the gonads and the maturation of follicles or spermatogonia. GnRH levels are low and basically constant until the onset of puberty, at which point cyclic release of GnRH begins, alternating between high and low levels to stimulate FSH and LH release throughout the reproductive years. FSH and LH are not released except under the influence of GnRH from the hypothalamus (this is true of other pituitary hormones under the control of the hypothalamus, like thyroid-stimulating hormone or growth hormone; they are only released from the pituitary upon stimulation from the hypothalamus). Thus, in order to cause the onset of puberty and sustain sexual maturation in an individual whose hypothalamus has been removed, GnRH would have to be administered over the lifetime of the individual. Testosterone or estrogen/progesterone would have to be administered over the lifetime of the individual as well. If there is no drive from GnRH, there will be no release of FSH/LH, and thus no release of androgens/estrogens that drive the start of puberty and sustain sexual maturation over the lifetime of the individual. Hence, the treatment will have to be life-long.