| PLASMA
Ca2+ |
|
|
|
|
|
|
|
|
| CALCIUM
SENSOR |
|||||||
| DECREASE
IN PLASMA |
|||||||
| CALCIUM
STIMULATES |
|||||||
| PARATHYROID |
|||||||
| HORMONE
(PTH) SECRETION |
|||||||
| CHOLESTEROL |
| PARATHYROID |
| VITAMIN
D3 |
| PTH |
| 25-(OH)-D3 |
| PTH |
| PO4 |
| GUT |
| BONE |
| KIDNEY |
| 1,25-(OH)2-D3 |
| Ca2+ |
|
|
|
| CALCIUM
REABSORPTION |
||
| PHOSPHATE
EXCRETION |
||
| PO4 |
| Ca2+ |
| URINE |
|
|
|
|
|
|
| INCREASE
IN PLASMA CALCIUM |
|||||
| STIMULATES
CALCITONIN |
|||||
| SECRETION
FROM THYROID |
|||||
| PARAFOLLICULAR
CELLS |
|||||
| PLASMA
Ca2+ |