During an acute bacterial infection, which type of white blood cell is expected to increase in number?

A. Adrenocorticotropic hormone (ACTH):ACTH stimulates the adrenal cortex to secrete cortisol; overproduction of ACTH causes Cushing disease features rather than the soft-tissue/bone overgrowth seen in acromegaly.
B. Prolactin:Prolactin excess causes galactorrhea and reproductive disturbances; it does not produce the characteristic enlarged hands, feet, and facial features of acromegaly.
C. Thyroid-stimulating hormone (TSH):Excess TSH leads to hyperthyroidism, which causes metabolic and sympathetic symptoms, not the skeletal overgrowth typical of acromegaly.
D. Growth hormone (GH):Excess GH from a pituitary adenoma stimulates increased IGF-1 production, promoting soft-tissue and bone growth that leads to the characteristic enlargement of the hands, feet, and facial bones in acromegaly.

A. The HPA axis directly controls the release of growth hormone.:Growth hormone release is regulated mainly by GHRH and somatostatin from the hypothalamus and feedback from IGF-1, not primarily by the HPA axis.
B. The HPA axis is responsible for regulating blood sugar levels through insulin secretion.:Insulin secretion is controlled by the pancreas in response to blood glucose; the HPA axis influences glucose metabolism indirectly via cortisol but does not control insulin release.
C. The HPA axis responds to stress by stimulating cortisol release from the adrenal glands.:The HPA axis (CRH → ACTH → cortisol) is activated by stress and results in increased cortisol production by the adrenal cortex.
D. The HPA axis regulates the secretion of thyroid hormones.:Thyroid hormone secretion is primarily regulated by the hypothalamic–pituitary–thyroid axis (TRH → TSH → T3/T4), not the HPA axis.