Search results
Results From The WOW.Com Content Network
Pituicytes are located in the pars nervosa of the posterior pituitary and interspersed with unmyelinated axons and Herring bodies.They generally stain dark purple with an H&E stain and are among the easiest structures to identify in the region.
Anterior_and_posterior_pituitary.jpg (630 × 240 pixels, file size: 28 KB, MIME type: image/jpeg) This is a file from the Wikimedia Commons . Information from its description page there is shown below.
The posterior pituitary is not glandular as is the anterior pituitary. Instead, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary, and serve as a site for the secretion of neurohypophysial hormones ( oxytocin and vasopressin ) directly into the blood. [ 2 ]
Leydig cells release a class of hormones called androgens (19-carbon steroids). [8] They secrete testosterone, androstenedione and dehydroepiandrosterone (DHEA), when stimulated by the luteinizing hormone (LH), which is released from the anterior pituitary in response to gonadotropin releasing hormone which in turn is released by the hypothalamus.
The process occurs as follows: in some hypothalamic cells there are osmoreceptors which respond to hyperosmolality in body fluids by signalling the posterior pituitary gland to secrete ADH. [6] This keeps serum sodium concentration – a proxy for solute concentration – at normal levels, prevents hypernatremia and turns off the osmoreceptors ...
The PVN contains magnocellular neurosecretory cells whose axons extend into the posterior pituitary, parvocellular neurosecretory cells that project to the median eminence, ultimately signalling to the anterior pituitary, and several populations of other cells that project to many different brain regions including parvocellular preautonomic cells that project to the brainstem and spinal cord.
Spoilers ahead! We've warned you. We mean it. Read no further until you really want some clues or you've completely given up and want the answers ASAP. Get ready for all of today's NYT ...
Damage to the pituitary stalk blocks the release of antidiuretic hormone, resulting in polydipsia (excessive water intake) and polyuria (excessive urination, central diabetes insipidus). The diameter of the pituitary stalk at the level of optic chiasm is 3.3 mm, and at the pituitary gland insertion site is measured at 1.9 mm. [3]