Question

Hypopituitarism may result from trauma, such as an automobile accident severing the stalk connecting the hypothalamus and anterior pituitary, or from tumors of the pituitary gland. In trauma, usually all of the releasing hormones from hypothalamus fail to reach the anterior pituitary. With a tumor of the gland, some or all of the pituitary hormones may be shut off. Posterior pituitary hormones may also be lost. Hypopituitarism can be life threatening. Usual therapy is administration of end organ hormones in oral form. In hypopituitarism the ovarian cyde would be affected because A. FSH and LH are synthesized in the anterior pituitary. B. gonadotropin-releasing hormone (GnRH) from the hypothalamus stimulates the release of \(\mathrm{FSH}\) and \(\mathrm{LH}\). C. inhibins would be secreted in much larger than normal amounts. D. the corpus luteum would be maintained. E. GnRH would bind to receptors to activate protein kinase A.

Short answer

A) Insufficient levels of FSH and LH B) Disrupted GnRH activity C) An increase in secretion of inhibins D) Disruption in the formation of corpus luteum E) Disruption in protein kinase A activation after binding to GnRH receptors Answer: A) Insufficient levels of FSH and LH, and B) Disrupted GnRH activity.

Step-by-step solution

Understanding Hypopituitarism

Hypopituitarism is a condition which results from deficient secretion of hormones from the pituitary gland. These hormones play an important role in the bodily functions ranging from growth to metabolism, sexual function and much more. Therefore, in such a case, the functioning of many organs/systems like ovaries would be impacted.

Examining option A

Follicle stimulating hormone (FSH) and Luteinizing hormone (LH) are synthesized and released by the anterior pituitary. These hormones play a critical role in the regulation of the ovarian cycle, fertility and reproduction. Hence, when hypopituitarism occurs, insufficient levels of these hormones impact the ovarian cycle.

Evaluating option B

GnRH (gonadotropin-releasing hormone) is secreted by the hypothalamus, which further stimulates the pituitary gland to release FSH and LH. These hormones aid in the ovarian cycle regulation. Under hypopituitarism, the communication between these organs may be disrupted, hampering the hormonal balance and ovarian cycle.

Assessing option C

Inhibins are hormones that inhibit the secretion of FSH. Under normal conditions, they maintain hormonal balance. However, if their secretion is substantially increased, as suggested by this option, it could disrupt the hormonal balance and impair the ovarian cycle.

Checking option D

The corpus luteum has a role in the latter half of the ovarian cycle, secreting progesterone which prepares the uterus for pregnancy. If hypopituitarism impacts this part, it may disrupt the ovarian cycle.

Analyzing option E

GnRH stimulates protein kinase A through binding to its receptors. This is a part of the hormonal crosstalk between the hypothalamus and pituitary gland, contributing to the regulation of the ovarian cycle. A disruption in this would likely affect the ovarian cycle.

Concluding Remarks

Upon close evaluation, it can be said that options A and B most directly explain the impact on the ovarian cycle in hypopituitarism since FSH, LH and GnRH play significant roles in the regulation of the ovarian cycle and are directly impacted due to the condition. Although the others may also contribute, the direct impact of insufficient FSH and LH along with disrupted GnRH activity make A and B the most correct choices.