Abstract
PTH stimulates active Ca reabsorption in isolated perfused rabbit kidney connecting tubules (CNTs). The existence of PTH-sensitive adenylate cyclase and the reproduction of increased epithelial Ca transport by dibutyryl-cAMP suggest that cAMP is the mediator. Accordingly, we studied the effects of PTH and 8-bromoadenosine 3',5'-cAMP (8-Br-cAMP) on cytosolic free calcium concentration [( Ca2+]i) in individual rabbit CNTs. [Ca2+]i was estimated by continuous epifluorescence microscopy of single fura-2-loaded tubules during dual wave-length excitation. In nonperfused controls at 37 degrees C, [Ca2+]i decreased with time. In contrast to vehicle controls, synthetic bovine (1-34) PTH (0.1 nM) increased [Ca2+]i within 4 min, produced a maximal effect in 7.2 min, and sustained its effect for at least 2 min after washout. 8-Br-cAMP (1 mM) mimicked the effect of PTH, but with an earlier onset of action. To test the hypothesis that lumen Ca is the predominant source of the rise in [Ca2+]i, we studied singly perfused CNTs. In the absence of bath and lumen Ca, PTH elicited no rise in [Ca2+]i, implying that intracellular Ca stores are not the major source. In contrast, there was a rise when Ca was replenished in both media. In the continuous presence of bath Ca, lumen Ca was estimated to contribute 65% of the total rise in [Ca2+]i in response to PTH when it was first deleted and then replenished. However, when the sequence of lumen Ca manipulation was reversed, the contributions by lumen and bath Ca were found to be essentially equal. We conclude (a) at a physiologic concentration, PTH increases [Ca2+]i in rabbit CNTs, (b) 8-Br-cAMP mimics this action, implicating cAMP as a second messenger, and (c) the PTH-stimulated rise in [Ca2+]i depends importantly on both bath and tubular luminal fluid Ca.
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- Bonventre J. V., Cheung J. Y. Cytosolic free calcium concentration in cultured renal epithelial cells. Am J Physiol. 1986 Feb;250(2 Pt 2):F329–F338. doi: 10.1152/ajprenal.1986.250.2.F329. [DOI] [PubMed] [Google Scholar]
- Bonventre J. V., Skorecki K. L., Kreisberg J. I., Cheung J. Y. Vasopressin increases cytosolic free calcium concentration in glomerular mesangial cells. Am J Physiol. 1986 Jul;251(1 Pt 2):F94–102. doi: 10.1152/ajprenal.1986.251.1.F94. [DOI] [PubMed] [Google Scholar]
- Borle A. B., Uchikawa T. Effects of adenosine 3',5'-monophosphate, dibutyryl adenosine 3',5'-monophosphate, aminophylline, and imidazole on renal cellular calcium metabolism. Endocrinology. 1979 Jan;104(1):122–129. doi: 10.1210/endo-104-1-122. [DOI] [PubMed] [Google Scholar]
- Borle A. B., Uchikawa T. Effects of parathyroid hormone on the distribution and transport of calcium in cultured kidney cells. Endocrinology. 1978 Jun;102(6):1725–1732. doi: 10.1210/endo-102-6-1725. [DOI] [PubMed] [Google Scholar]
- Bourdeau J. E., Bouillon R., Zikos D., Langman C. B. Renal responses to calcium deprivation in young rabbits. Miner Electrolyte Metab. 1988;14(2-3):150–157. [PubMed] [Google Scholar]
- Bourdeau J. E., Burg M. B. Effect of PTH on calcium transport across the cortical thick ascending limb of Henle's loop. Am J Physiol. 1980 Aug;239(2):F121–F126. doi: 10.1152/ajprenal.1980.239.2.F121. [DOI] [PubMed] [Google Scholar]
- Bourdeau J. E. Calcium transport across the pars recta of cortical segment 2 proximal tubules. Am J Physiol. 1986 Oct;251(4 Pt 2):F718–F724. doi: 10.1152/ajprenal.1986.251.4.F718. [DOI] [PubMed] [Google Scholar]
- Bourdeau J. E., Langman C. B., Bouillon R. Parathyroid hormone-stimulated calcium absorption in cTAL from vitamin D-deficient rabbits. Kidney Int. 1987 Apr;31(4):913–917. doi: 10.1038/ki.1987.85. [DOI] [PubMed] [Google Scholar]
- Burg M. B. Perfusion of isolated renal tubules. Yale J Biol Med. 1972 Jun-Aug;45(3-4):321–326. [PMC free article] [PubMed] [Google Scholar]
- Burg M., Grantham J., Abramow M., Orloff J. Preparation and study of fragments of single rabbit nephrons. Am J Physiol. 1966 Jun;210(6):1293–1298. doi: 10.1152/ajplegacy.1966.210.6.1293. [DOI] [PubMed] [Google Scholar]
- Chabardès D., Imbert M., Clique A., Montégut M., Morel F. PTH sensitive adenyl cyclase activity in different segments of the rabbit nephron. Pflugers Arch. 1975;354(3):229–239. doi: 10.1007/BF00584646. [DOI] [PubMed] [Google Scholar]
- Cheung J. Y., Constantine J. M., Bonventre J. V. Regulation of cytosolic free calcium concentration in cultured renal epithelial cells. Am J Physiol. 1986 Oct;251(4 Pt 2):F690–F701. doi: 10.1152/ajprenal.1986.251.4.F690. [DOI] [PubMed] [Google Scholar]
- Costanzo L. S. Localization of diuretic action in microperfused rat distal tubules: Ca and Na transport. Am J Physiol. 1985 Apr;248(4 Pt 2):F527–F535. doi: 10.1152/ajprenal.1985.248.4.F527. [DOI] [PubMed] [Google Scholar]
- Costanzo L. S., Windhager E. E. Calcium and sodium transport by the distal convoluted tubule of the rat. Am J Physiol. 1978 Nov;235(5):F492–F506. doi: 10.1152/ajprenal.1978.235.5.F492. [DOI] [PubMed] [Google Scholar]
- Costanzo L. S., Windhager E. E. Effects of PTH, ADH, and cyclic AMP on distal tubular Ca and Na reabsorption. Am J Physiol. 1980 Nov;239(5):F478–F485. doi: 10.1152/ajprenal.1980.239.5.F478. [DOI] [PubMed] [Google Scholar]
- Dolson G. M., Hise M. K., Weinman E. J. Relationship among parathyroid hormone, cAMP, and calcium on proximal tubule sodium transport. Am J Physiol. 1985 Sep;249(3 Pt 2):F409–F416. doi: 10.1152/ajprenal.1985.249.3.F409. [DOI] [PubMed] [Google Scholar]
- Goligorsky M. S., Loftus D. J., Hruska K. A. Cytoplasmic calcium in individual proximal tubular cells in culture. Am J Physiol. 1986 Nov;251(5 Pt 2):F938–F944. doi: 10.1152/ajprenal.1986.251.5.F938. [DOI] [PubMed] [Google Scholar]
- Goligorsky M. S., Menton D. N., Hruska K. A. Parathyroid hormone-induced changes of the brush border topography and cytoskeleton in cultured renal proximal tubular cells. J Membr Biol. 1986;92(2):151–162. doi: 10.1007/BF01870704. [DOI] [PubMed] [Google Scholar]
- Grynkiewicz G., Poenie M., Tsien R. Y. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem. 1985 Mar 25;260(6):3440–3450. [PubMed] [Google Scholar]
- Hassid A., Pidikiti N., Gamero D. Effects of vasoactive peptides on cytosolic calcium in cultured mesangial cells. Am J Physiol. 1986 Dec;251(6 Pt 2):F1018–F1028. doi: 10.1152/ajprenal.1986.251.6.F1018. [DOI] [PubMed] [Google Scholar]
- Hruska K. A., Goligorsky M., Scoble J., Tsutsumi M., Westbrook S., Moskowitz D. Effects of parathyroid hormone on cytosolic calcium in renal proximal tubular primary cultures. Am J Physiol. 1986 Aug;251(2 Pt 2):F188–F198. doi: 10.1152/ajprenal.1986.251.2.F188. [DOI] [PubMed] [Google Scholar]
- Hruska K. A., Moskowitz D., Esbrit P., Civitelli R., Westbrook S., Huskey M. Stimulation of inositol trisphosphate and diacylglycerol production in renal tubular cells by parathyroid hormone. J Clin Invest. 1987 Jan;79(1):230–239. doi: 10.1172/JCI112788. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Imai M. Effects of parathyroid hormone and N6,O2'-dibutyryl cyclic AMP on Ca2+ transport across the rabbit distal nephron segments perfused in vitro. Pflugers Arch. 1981 May;390(2):145–151. doi: 10.1007/BF00590197. [DOI] [PubMed] [Google Scholar]
- Lau K., Agus Z. S., Goldberg M., Goldfarb S. Renal tubular sites of altered calcium transport in phosphate-depleted rats. J Clin Invest. 1979 Dec;64(6):1681–1687. doi: 10.1172/JCI109630. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lau K., Goldfarb S., Goldberg M., Agus Z. S. Effects of phosphate administration on tubular calcium transport. J Lab Clin Med. 1982 Mar;99(3):317–324. [PubMed] [Google Scholar]
- McKinney T. D., Myers P. Bicarbonate transport by proximal tubules: effect of parathyroid hormone and dibutyryl cyclic AMP. Am J Physiol. 1980 Mar;238(3):F166–F174. doi: 10.1152/ajprenal.1980.238.3.F166. [DOI] [PubMed] [Google Scholar]
- Murphy E., Chamberlin M. E., Mandel L. J. Effects of calcitonin on cytosolic Ca in a suspension of rabbit medullary thick ascending limb tubules. Am J Physiol. 1986 Oct;251(4 Pt 1):C491–C495. doi: 10.1152/ajpcell.1986.251.4.C491. [DOI] [PubMed] [Google Scholar]
- Nagata N., Rasmussen H. Parathyroid hormone, 3'5' AMP, Ca++, and renal gluconeogenesis. Proc Natl Acad Sci U S A. 1970 Feb;65(2):368–374. doi: 10.1073/pnas.65.2.368. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pollock A. S., Warnock D. G., Strewler G. J. Parathyroid hormone inhibition of Na+-H+ antiporter activity in a cultured renal cell line. Am J Physiol. 1986 Feb;250(2 Pt 2):F217–F225. doi: 10.1152/ajprenal.1986.250.2.F217. [DOI] [PubMed] [Google Scholar]
- Shareghi G. R., Agus Z. S. Magnesium transport in the cortical thick ascending limb of Henle's loop of the rabbit. J Clin Invest. 1982 Apr;69(4):759–769. doi: 10.1172/JCI110514. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shareghi G. R., Stoner L. C. Calcium transport across segments of the rabbit distal nephron in vitro. Am J Physiol. 1978 Oct;235(4):F367–F375. doi: 10.1152/ajprenal.1978.235.4.F367. [DOI] [PubMed] [Google Scholar]
- Suki W. N., Rouse D. Hormonal regulation of calcium transport in thick ascending limb renal tubules. Am J Physiol. 1981 Aug;241(2):F171–F174. doi: 10.1152/ajprenal.1981.241.2.F171. [DOI] [PubMed] [Google Scholar]
- Teitelbaum I., Berl T. Effects of calcium on vasopressin-mediated cyclic adenosine monophosphate formation in cultured rat inner medullary collecting tubule cells. Evidence for the role of intracellular calcium. J Clin Invest. 1986 May;77(5):1574–1583. doi: 10.1172/JCI112473. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tsien R. Y., Rink T. J., Poenie M. Measurement of cytosolic free Ca2+ in individual small cells using fluorescence microscopy with dual excitation wavelengths. Cell Calcium. 1985 Apr;6(1-2):145–157. doi: 10.1016/0143-4160(85)90041-7. [DOI] [PubMed] [Google Scholar]
- Yamaguchi D. T., Hahn T. J., Iida-Klein A., Kleeman C. R., Muallem S. Parathyroid hormone-activated calcium channels in an osteoblast-like clonal osteosarcoma cell line. cAMP-dependent and cAMP-independent calcium channels. J Biol Chem. 1987 Jun 5;262(16):7711–7718. [PubMed] [Google Scholar]
- Yanagawa N., Jo O. D. Possible role of calcium in parathyroid hormone actions in rabbit renal proximal tubules. Am J Physiol. 1986 May;250(5 Pt 2):F942–F948. doi: 10.1152/ajprenal.1986.250.5.F942. [DOI] [PubMed] [Google Scholar]