can hormones which released from hyphothalamus inhibit or stimulate the releasing of hormones from posterior pituitary gland

Answer 1

Yes, hormones released from the hypothalamus can both inhibit and stimulate the release of hormones from the posterior pituitary gland. The hypothalamus produces hormones known as releasing hormones and inhibiting hormones, which regulate the secretion of hormones from the anterior pituitary and the posterior pituitary glands.

In the case of the posterior pituitary gland, it does not actually produce its own hormones but stores and releases two hormones that are synthesized by the hypothalamus. These two hormones are oxytocin and antidiuretic hormone (ADH), also known as vasopressin.

The hypothalamus releases oxytocin and ADH into the posterior pituitary gland, which then secretes them into the bloodstream. However, the release of these hormones from the posterior pituitary gland is regulated by the hypothalamus itself.

For example, the hypothalamus can release oxytocin in response to stimuli such as nipple stimulation during breastfeeding or uterine contractions during labor. On the other hand, it can also release ADH in response to dehydration or low blood pressure.

So, in summary, the hypothalamus can both stimulate (e.g., by releasing oxytocin and ADH) and inhibit (e.g., by withholding the release of oxytocin and ADH) the secretion of hormones from the posterior pituitary gland.