Calcium Metabolism

Which is Correct among the following options regarding Passive calcium absorption?

Correct! Wrong!

Intestinal absorption of ingested calcium involves both active (transcellular) and passive (paracellular) mechanisms.


Passive calcium absorption is nonsaturable and approximates 5% of daily calcium intake, whereas active absorption normally ranges from 20 to 70%.

Ion channels expression for active absorption of calcium is controlled mainly by?

Correct! Wrong!

Active absorption involves apical calcium entry via specific ion channels (TRPV5 and TRPV6), whose expression is controlled principally by 1,25(OH)2 D,

Active calcium transport occurs mainly in -

Correct! Wrong!

Active calcium transport occurs mainly in the proximal small bowel - duodenum and proximal jejunum.

Supplement of choice for individuals with achlorhydria -

Correct! Wrong!

Supplement of choice for individuals with achlorhydria -Calcium citrate. Calcium citrate can be taken without food and is the supplement of choice for individuals with achlorhydria or who are taking histamine-2 blockers or proton-pump inhibitors.

Which are the ion channels responsible for active absorption involving apical calcium entry?

Correct! Wrong!

Active absorption involving apical calcium entry through specific ion channels TRPV5 and TRPV6. TRPV5 and TRPV6 - expression is controlled principally by 1,25(OH)2D,


TRPV5 is mainly expressed in kidney epithelial cells, where it plays an important role in the reabsorption of Ca2+, whereas TRPV6 is mainly expressed in the intestine.

Which calcium channel blockers are used to treat Hypertension?

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L-type calcium channel blockers are used to treat hypertension.

Which calcium channel blockers are used to treat EPILEPSY?

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T-type calcium channel blockers are used to treat epilepsy.


Increased calcium conductance in the neurons leads to increased depolarization and excitability. This leads to a greater predisposition to epileptic episodes. Calcium channel blockers reduce the neuronal calcium conductance and reduce the likelihood of experiencing epileptic attack

Which preparation of Calcium depends on low pH levels for proper absorption in the intestine?

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Calcium Carbonate - Preparation of Calcium depends on low pH levels or acidic PH for proper absorption in the intestine.

Estrogen loss in postmenopausal women is responsible for all of the following EXCEPT -

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Estrogen loss - Increases the rate of bone remodeling


Decreased intestinal absorption of calcium
Increased urinary loss of calcium

Which is the most common granulomatous disease associated with hypercalcemia?

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Sarcoidosis is also the most common granulomatous disease associated with hypercalcemia. Approximately 10%–20% of patients with sarcoidosis may develop hypercalcemia