Abstract
We used the "perforated-patch" technique (Horn, R., and A. Marty, 1988. Journal of General Physiology. 92:145-159) to examine the effects of adrenergic agonists on the membrane potentials and membrane currents in isolated cultured brown fat cells from neonatal rats. In contrast to our previous results using traditional whole-cell patch clamp, 1-23-d cultured brown fat cells clamped with the perforated patch consistently showed vigorous membrane responses to both alpha- and beta-adrenergic agonists, suggesting that cytoplasmic components essential for the thermogenic response are lost in whole-cell experiments. The membrane responses to adrenergic stimulation varied from cell to cell but were consistent for a given cell. Responses to bath-applied norepinephrine in voltage-clamped cells had three possible components: (a) a fast transient inward current, (b) a slower outward current carried by K+ that often oscillated in amplitude, and (c) a sustained inward current largely by Na+. The fast inward and outward currents were activated by alpha-adrenergic agonists while the slow inward current was mediated by beta-adrenergic agonists. Oscillating outward currents were the most frequently seen response to norepinephrine stimulation. Activation of this current, termed IK,NE, was independent of voltage and seemed to be carried by Ca2(+)-activated K channels since the current oscillated in amplitude at constant membrane potential and gradually decreased when the cells were bathed with calcium-free external solution. IK,NE had a novel pharmacology in that it could be blocked by 4-aminopyridine, tetraethylammonium, apamin, and charybdotoxin. Both IK,NE and the voltage-gated K channels also present in brown fat (Lucero, M. T., and P. A. Pappone, 1989a. Journal of General Physiology. 93:451-472) may play a role in maintaining cellular homeostasis in the face of the high metabolic activity involved in thermogenesis.
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- Berridge M. J., Galione A. Cytosolic calcium oscillators. FASEB J. 1988 Dec;2(15):3074–3082. doi: 10.1096/fasebj.2.15.2847949. [DOI] [PubMed] [Google Scholar]
- Berridge M. J. Inositol trisphosphate and diacylglycerol: two interacting second messengers. Annu Rev Biochem. 1987;56:159–193. doi: 10.1146/annurev.bi.56.070187.001111. [DOI] [PubMed] [Google Scholar]
- Bezanilla F. A high capacity data recording device based on a digital audio processor and a video cassette recorder. Biophys J. 1985 Mar;47(3):437–441. doi: 10.1016/S0006-3495(85)83935-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cahalan M. D., Chandy K. G., DeCoursey T. E., Gupta S. A voltage-gated potassium channel in human T lymphocytes. J Physiol. 1985 Jan;358:197–237. doi: 10.1113/jphysiol.1985.sp015548. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Castle N. A., Haylett D. G., Jenkinson D. H. Toxins in the characterization of potassium channels. Trends Neurosci. 1989 Feb;12(2):59–65. doi: 10.1016/0166-2236(89)90137-9. [DOI] [PubMed] [Google Scholar]
- Chiu S. Y., Wilson G. F. The role of potassium channels in Schwann cell proliferation in Wallerian degeneration of explant rabbit sciatic nerves. J Physiol. 1989 Jan;408:199–222. doi: 10.1113/jphysiol.1989.sp017455. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Christensen O. Mediation of cell volume regulation by Ca2+ influx through stretch-activated channels. Nature. 1987 Nov 5;330(6143):66–68. doi: 10.1038/330066a0. [DOI] [PubMed] [Google Scholar]
- Connolly E., Nedergaard J. Beta-adrenergic modulation of Ca2+ uptake by isolated brown adipocytes. Possible involvement of mitochondria. J Biol Chem. 1988 Aug 5;263(22):10574–10582. [PubMed] [Google Scholar]
- Connolly E., Nånberg E., Nedergaard J. Na+-dependent, alpha-adrenergic mobilization of intracellular (mitochondrial) Ca2+ in brown adipocytes. Eur J Biochem. 1984 May 15;141(1):187–193. doi: 10.1111/j.1432-1033.1984.tb08173.x. [DOI] [PubMed] [Google Scholar]
- Connolly E., Nånberg E., Nedergaard J. Norepinephrine-induced Na+ influx in brown adipocytes is cyclic AMP-mediated. J Biol Chem. 1986 Nov 5;261(31):14377–14385. [PubMed] [Google Scholar]
- Cunningham S. A., Nicholls D. G. Induction of functional uncoupling protein in guinea pigs infused with noradrenaline. Studies with isolated brown adipocytes. Biochem J. 1987 Jul 15;245(2):485–491. doi: 10.1042/bj2450485. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DeCoursey T. E., Chandy K. G., Gupta S., Cahalan M. D. Voltage-gated K+ channels in human T lymphocytes: a role in mitogenesis? Nature. 1984 Feb 2;307(5950):465–468. doi: 10.1038/307465a0. [DOI] [PubMed] [Google Scholar]
- Fain J. N., Reed N., Saperstein R. The isolation and metabolism of brown fat cells. J Biol Chem. 1967 Apr 25;242(8):1887–1894. [PubMed] [Google Scholar]
- Fink S. A., Williams J. A. Adrenergic receptors mediating depolarization in brown adipose tissue. Am J Physiol. 1976 Sep;231(3):700–706. doi: 10.1152/ajplegacy.1976.231.3.700. [DOI] [PubMed] [Google Scholar]
- Flaim K. E., Horwitz B. A., Horowitz J. M. Coupling of signals to brown fat: alpha- and beta-adrenergic responses in intact rats. Am J Physiol. 1977 Mar;232(3):R101–R109. doi: 10.1152/ajpregu.1977.232.3.R101. [DOI] [PubMed] [Google Scholar]
- Garcia-Sáinz J. A., Hasler A. K., Fain J. N. Alpha1-adrenergic activation of phosphatidylinositol labeling in isolated brown fat cells. Biochem Pharmacol. 1980 Dec;29(24):3330–3333. doi: 10.1016/0006-2952(80)90313-5. [DOI] [PubMed] [Google Scholar]
- Giovannini P., Seydoux J., Girardier L. Evidence for a modulating effect of Na+/H+ exchange on the metabolic response of rat brown adipose tissue. Pflugers Arch. 1988 Mar;411(3):273–277. doi: 10.1007/BF00585114. [DOI] [PubMed] [Google Scholar]
- Girardier L., Schneider-Picard G. Alpha and beta-adrenergic mediation of membrane potential changes and metabolism in rat brown adipose tissue. J Physiol. 1983 Feb;335:629–641. doi: 10.1113/jphysiol.1983.sp014555. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Girardier L., Seydoux J., Clausen T. Membrane potential of brown adipose tissue. A suggested mechanism for the regulation of thermogenesis. J Gen Physiol. 1968 Dec;52(6):925–940. doi: 10.1085/jgp.52.6.925. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
- Horn R., Marty A. Muscarinic activation of ionic currents measured by a new whole-cell recording method. J Gen Physiol. 1988 Aug;92(2):145–159. doi: 10.1085/jgp.92.2.145. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Horowitz J. M., Horwitz B. A., Smith R. E. Effect in vivo of norepinephrine on the membrane resistance of brown fat cells. Experientia. 1971 Dec 15;27(12):1419–1421. doi: 10.1007/BF02154265. [DOI] [PubMed] [Google Scholar]
- Horwitz B. A., Hamilton J. Alpha-adrenergic-induced changes in hamster (Mesocricetus) brown adipocyte respiration and membrane potential. Comp Biochem Physiol C. 1984;78(1):99–104. doi: 10.1016/0742-8413(84)90053-7. [DOI] [PubMed] [Google Scholar]
- Horwitz B. A., Horowitz J. M., Jr, Smith R. E. Norepinephrine-induced depolarization of brown fat cells. Proc Natl Acad Sci U S A. 1969 Sep;64(1):113–120. doi: 10.1073/pnas.64.1.113. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Igusa Y., Miyazaki S. Periodic increase of cytoplasmic free calcium in fertilized hamster eggs measured with calcium-sensitive electrodes. J Physiol. 1986 Aug;377:193–205. doi: 10.1113/jphysiol.1986.sp016181. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jacob R., Merritt J. E., Hallam T. J., Rink T. J. Repetitive spikes in cytoplasmic calcium evoked by histamine in human endothelial cells. Nature. 1988 Sep 1;335(6185):40–45. doi: 10.1038/335040a0. [DOI] [PubMed] [Google Scholar]
- Konishi T. Voltage-dependent potassium channels in mouse Schwann cells. J Physiol. 1989 Apr;411:115–130. doi: 10.1113/jphysiol.1989.sp017564. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Krishna G., Moskowitz J., Dempsey P., Brodie B. B. The effect of norepinephrine and insulin on brown fat cell membrane potentials. Life Sci I. 1970 Dec 1;9(23):1353–1361. doi: 10.1016/0024-3205(70)90043-3. [DOI] [PubMed] [Google Scholar]
- LaNoue K. F., Koch C., Strzelecka D., Kobylski T. P. Regulation of Na+ transport in brown adipose tissue. Biochem J. 1986 Apr 15;235(2):545–552. doi: 10.1042/bj2350545. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Latorre R., Oberhauser A., Labarca P., Alvarez O. Varieties of calcium-activated potassium channels. Annu Rev Physiol. 1989;51:385–399. doi: 10.1146/annurev.ph.51.030189.002125. [DOI] [PubMed] [Google Scholar]
- Lucero M. T., Pappone P. A. Voltage-gated potassium channels in brown fat cells. J Gen Physiol. 1989 Mar;93(3):451–472. doi: 10.1085/jgp.93.3.451. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moczydlowski E., Lucchesi K., Ravindran A. An emerging pharmacology of peptide toxins targeted against potassium channels. J Membr Biol. 1988 Oct;105(2):95–111. doi: 10.1007/BF02009164. [DOI] [PubMed] [Google Scholar]
- Mohell N., Connolly E., Nedergaard J. Distinction between mechanisms underlying alpha 1- and beta-adrenergic respiratory stimulation in brown fat cells. Am J Physiol. 1987 Aug;253(2 Pt 1):C301–C308. doi: 10.1152/ajpcell.1987.253.2.C301. [DOI] [PubMed] [Google Scholar]
- Mohell N., Nedergaard J., Cannon B. Quantitative differentiation of alpha- and beta-adrenergic respiratory responses in isolated hamster brown fat cells: evidence for the presence of an alpha 1-adrenergic component. Eur J Pharmacol. 1983 Sep 30;93(3-4):183–193. doi: 10.1016/0014-2999(83)90136-x. [DOI] [PubMed] [Google Scholar]
- Nedergaard J. Effects of cations on brown adipose tissue in relation to possible metabolic consequences of membrane depolarisation. Eur J Biochem. 1981;114(1):159–167. doi: 10.1111/j.1432-1033.1981.tb06187.x. [DOI] [PubMed] [Google Scholar]
- Nedergaard J., Lindberg O. The brown fat cell. Int Rev Cytol. 1982;74:187–286. doi: 10.1016/s0074-7696(08)61173-0. [DOI] [PubMed] [Google Scholar]
- Nicholls D. G. Hamster brown-adipose-tissue mitochondria. The control of respiration and the proton electrochemical potential gradient by possible physiological effectors of the proton conductance of the inner membrane. Eur J Biochem. 1974 Dec 2;49(3):573–583. doi: 10.1111/j.1432-1033.1974.tb03861.x. [DOI] [PubMed] [Google Scholar]
- Nicholls D. G., Locke R. M. Thermogenic mechanisms in brown fat. Physiol Rev. 1984 Jan;64(1):1–64. doi: 10.1152/physrev.1984.64.1.1. [DOI] [PubMed] [Google Scholar]
- Nånberg E., Connolly E., Nedergaard J. Presence of a Ca2+-dependent K+ channel in brown adipocytes. Possible role in maintenance of alpha 1-adrenergic stimulation. Biochim Biophys Acta. 1985 Jan 18;844(1):42–49. doi: 10.1016/0167-4889(85)90231-9. [DOI] [PubMed] [Google Scholar]
- Nånberg E., Nedergaard J., Cannon B. Alpha-adrenergic effects on 86Rb+ (K+) potentials and fluxes in brown fat cells. Biochim Biophys Acta. 1984 Jul 20;804(3):291–300. doi: 10.1016/0167-4889(84)90132-0. [DOI] [PubMed] [Google Scholar]
- Nånberg E., Putney J., Jr Alpha 1-adrenergic activation of brown adipocytes leads to an increased formation of inositol polyphosphates. FEBS Lett. 1986 Jan 20;195(1-2):319–322. doi: 10.1016/0014-5793(86)80185-5. [DOI] [PubMed] [Google Scholar]
- Petersen O. H., Maruyama Y. Calcium-activated potassium channels and their role in secretion. Nature. 1984 Feb 23;307(5953):693–696. doi: 10.1038/307693a0. [DOI] [PubMed] [Google Scholar]
- Prentki M., Glennon M. C., Thomas A. P., Morris R. L., Matschinsky F. M., Corkey B. E. Cell-specific patterns of oscillating free Ca2+ in carbamylcholine-stimulated insulinoma cells. J Biol Chem. 1988 Aug 15;263(23):11044–11047. [PubMed] [Google Scholar]
- Rink T. J., Jacob R. Calcium oscillations in non-excitable cells. Trends Neurosci. 1989 Feb;12(2):43–46. doi: 10.1016/0166-2236(89)90133-1. [DOI] [PubMed] [Google Scholar]
- Rudy B. Diversity and ubiquity of K channels. Neuroscience. 1988 Jun;25(3):729–749. doi: 10.1016/0306-4522(88)90033-4. [DOI] [PubMed] [Google Scholar]
- Russell J. M., Eaton D. C., Brodwick M. S. Effects of nystatin on membrane conductance and internal ion activities in Aplysia neurons. J Membr Biol. 1977 Oct;37(2):137–156. doi: 10.1007/BF01940929. [DOI] [PubMed] [Google Scholar]
- Schimmel R. J., Dzierzanowski D., Elliott M. E., Honeyman T. W. Stimulation of phosphoinositide metabolism in hamster brown adipocytes exposed to alpha 1-adrenergic agents and its inhibition with phorbol esters. Biochem J. 1986 Jun 15;236(3):757–764. doi: 10.1042/bj2360757. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schimmel R. J., McCarthy L., McMahon K. K. Alpha 1-adrenergic stimulation of hamster brown adipocyte respiration. Am J Physiol. 1983 May;244(5):C362–C368. doi: 10.1152/ajpcell.1983.244.5.C362. [DOI] [PubMed] [Google Scholar]
- Schneider-Picard G., Coles J. A., Girardier L. Alpha- and beta-adrenergic mediation of changes in metabolism and Na/K exchange in rat brown fat. J Gen Physiol. 1985 Aug;86(2):169–188. doi: 10.1085/jgp.86.2.169. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sheridan J. D. Electrical coupling between fat cells in newt fat body and mouse brown fat. J Cell Biol. 1971 Sep;50(3):795–803. doi: 10.1083/jcb.50.3.795. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Siemen D., Reuhl T. Non-selective cationic channel in primary cultured cells of brown adipose tissue. Pflugers Arch. 1987 May;408(5):534–536. doi: 10.1007/BF00585082. [DOI] [PubMed] [Google Scholar]
- Svoboda P., Svartengren J., Snochowski M., Houstek J., Cannon B. High number of high-affinity binding sites for (-)-[3H]dihydroalprenolol on isolated hamster brown-fat cells. A study of the beta-adrenergic receptors. Eur J Biochem. 1979 Dec;102(1):203–210. doi: 10.1111/j.1432-1033.1979.tb06281.x. [DOI] [PubMed] [Google Scholar]
- Williams J. A., Matthews E. K. Effects of ions and metabolic inhibitors on membrane potential of brown adipose tissue. Am J Physiol. 1974 Oct;227(4):981–986. doi: 10.1152/ajplegacy.1974.227.4.981. [DOI] [PubMed] [Google Scholar]
- Williams J. A., Matthews E. K. Membrane depolarization, cyclic AMP, and glycerol release by brown adipose tissue. Am J Physiol. 1974 Oct;227(4):987–992. doi: 10.1152/ajplegacy.1974.227.4.987. [DOI] [PubMed] [Google Scholar]
- Woods N. M., Cuthbertson K. S., Cobbold P. H. Repetitive transient rises in cytoplasmic free calcium in hormone-stimulated hepatocytes. Nature. 1986 Feb 13;319(6054):600–602. doi: 10.1038/319600a0. [DOI] [PubMed] [Google Scholar]