vitamin D

1. Diffusible Non-diffusible
Ca2+ concentration in ECF
(bood and interstitium)
• Free Ca2+ (50%)
• Action
potentials
• Contraction
muscles
• Hormon
secretion
• Blood
coagulation
• Ca2+ linked with
oxalate/phospate
• Electricallyneutral
• Not useful for
celluarprocesses
• Ca2+ bound
protein (40%)
• Albumin
• Large
• Charged
• Unenvolved in
cellular
processes

3. • Low • High
Ca2+ level
PTH Vitamin Dcalcitonin
2.25 - 2.75 mmol/L
phosphateconcentrationin plasma
0.8 - 1.6 mmol/L

4. Vitamin D

8. Vitamin D active form (1,25-OHVD)
• Increases
• calcium and phosphate levels
• In the ECF of
• Intestines,
• Kidneys
• bones

9. Vitamin D active form (1,25-OHVD)
• Increases
• calcium and phosphate
absorptionfrom the intestine
• Decreases
• their excretion with the urine

10. Vitamin D active form (1,25-OHVD)
• Promotes
• Bone calcification
• Stimulates
• calcium release from the bones
• Increases
• the production of calmodulin