Question

ACTH increases the amount of ____ available for glucocorticoid synthesis by increasing the delivery to the IMM. It also ____ the transcription of steroidogenic enzymes, including the side chain cleavage enzyme CYP____

a) Cholesterol; Enhances; CYP21A2
b) Glucose; Inhibits; CYP17A1
c) Cholesterol; Inhibits; CYP11A1
d) Glucose; Enhances; CYP19A1

Answer 1

The correct answer is c) Cholesterol; Enhances; CYP11A1, where ACTH increases cholesterol for glucocorticoid synthesis and enhances transcription of steroidogenic enzymes.

Step-by-step explanation:

ACTH (adrenocorticotropic hormone) increases the amount of cholesterol available for glucocorticoid synthesis by increasing the delivery to the inner mitochondrial membrane (IMM). It also enhances the transcription of steroidogenic enzymes, including the side chain cleavage enzyme CYP11A1. Therefore, the correct answer is c) Cholesterol; Enhances; CYP11A1.

Glucocorticoids such as cortisol and cortisone play a crucial role in metabolism and stress response. They stimulate the synthesis of glucose and gluconeogenesis by liver cells and increase blood glucose levels. These hormones are derived from cholesterol and their production is stimulated by ACTH via the hypothalamic-pituitary axis.