Final answer:
The blockade of dopamine receptors in tuberoinfundibular tracts results in increased prolactin levels, causing breast enlargement, galactorrhea, impotence, and amenorrhea.
Step-by-step explanation:
Blockade of dopamine receptors in the tuberoinfundibular tracts leads to increased levels of prolactin, which is responsible for various physiological effects, including breast enlargement, galactorrhea (the discharge of milk outside of the normal period of nursing), impotence, and amenorrhea (absence of menstruation). Prolactin has multiple actions, including the development of mammary tissue and milk production. Additionally, prolactin aids in erection of genitalia in both sexes during sexual arousal, and it is involved in the transport of gonadotropic hormones that regulate reproductive functions. Increased prolactin can disrupt the regulation of reproductive hormones such as GnRH, LH, and FSH, leading to sexual dysfunction and changes in menstrual cycles.