Clark N B, Wideman R F
Am J Physiol. 1977 Aug;233(2):F138-44. doi: 10.1152/ajprenal.1977.233.2.F138.
Renal excretion patterns of calcium, phosphate, sodium, and potassium were studied in parathyroidectomized (PTX) and parathyroid extract (PTE)-injected PTX starlings. Sturnus vulgaris. Anesthetized birds (Equi-Thesin or Dial) were infused intravenously with 2.5% mannitol containing [14C]inulin. PTX caused significant hypocalcemia, hyperphosphatemia, increased relative calcium clearance (CCa/CIn), and decreased relative clearances of phosphate and potassium, but did not change the clearance of sodium. Glomerular filtration rate (GFR=CIn) and urine flow remained unchanged up to 2 h after PTX. PTE administration 3 h after PTX returned serum calcium and phosphate values to control levels and caused a transient (10-min) increase in GFR. Following PTE, the relative clearances of phosphate, sodium- and potassium increased, while that of calcium decreased significantly relative to the PTX levels. PTE caused net tubular secretion of phosphate, decreased tubular reabsorption of sodium and potassium (sometimes potassium secretion), and a return of excretion of calcium to control levels. These studies indicate that the parathyroid role in calcium and phosphate homeostasis in starlings is predominantly on the kidney.
在摘除甲状旁腺（PTX）以及注射甲状旁腺提取物（PTE）的欧椋鸟（普通椋鸟）中研究了钙、磷、钠和钾的肾排泄模式。对麻醉的鸟类（用速眠新或狄奥）静脉输注含[14C]菊粉的2.5%甘露醇。PTX导致显著的低钙血症、高磷血症、相对钙清除率（CCa/CIn）增加，以及磷酸盐和钾的相对清除率降低，但钠清除率未改变。在PTX后长达2小时内，肾小球滤过率（GFR = CIn）和尿流保持不变。PTX后3小时给予PTE使血清钙和磷值恢复到对照水平，并导致GFR短暂（10分钟）增加。给予PTE后，磷酸盐、钠和钾的相对清除率增加，而钙的相对清除率相对于PTX水平显著降低。PTE导致磷酸盐的肾小管净分泌，钠和钾的肾小管重吸收减少（有时钾分泌），以及钙排泄恢复到对照水平。这些研究表明，甲状旁腺在欧椋鸟钙和磷稳态中的作用主要在肾脏。
