Correct option is A
Explanation:
Calcitonin is a hormone produced by the thyroid gland that helps regulate calcium levels in the blood. It acts on bone and kidney cells to lower blood calcium levels. Calcitonin elicits its cellular response through the cAMP (cyclic adenosine monophosphate) signaling pathway. When calcitonin binds to its receptor on target cells, it activates adenylate cyclase, which converts ATP to cAMP. This cAMP acts as a second messenger to initiate the cellular responses associated with calcitonin action.
Information Booster:
cAMP is a second messenger involved in many signaling pathways, including those triggered by hormones like calcitonin, oxytocin, and others.
Calcitonin activates adenylate cyclase, producing cAMP, which then triggers a cascade of intracellular events to lower blood calcium levels.
The cAMP pathway is involved in numerous other hormonal responses in various cell types, influencing diverse physiological processes like metabolism and growth.
Additional Knowledge:
Oxytocin (option 2) primarily uses the phosphoinositide pathway, not cAMP, to elicit its responses related to childbirth and lactation.
Prolactin (option 3) primarily acts through JAK-STAT signaling, which does not involve cAMP as a second messenger.
Leptin (option 4) regulates appetite and energy balance through the JAK-STAT pathway, and cAMP is not involved in leptin signaling.
