G-PROTEIN AND CAPACITATIVELY REGULATED CA2+ ENTRY PATHWAYS ARE ACTIVATED BY MUSCARINIC RECEPTOR STIMULATION IN A HUMAN SUBMANDIBULAR DUCTAL CELL-LINE

被引:22
作者
KAPLAN, MD
TAYLOR, SE
AMBUDKAR, IS
机构
[1] NIDR,CLIN INVEST & PATIENT CARE BRANCH,BETHESDA,MD 20892
[2] BAYLOR COLL DENT,DEPT ORAL SURG & PHARMACOL,DALLAS,TX 75246
来源
PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY | 1994年 / 428卷 / 5-6期
关键词
CA2+ INFLUX; G-PROTEIN; MUSCARINIC RECEPTOR; CARBACHOL; THAPSIGARGIN; SALIVARY GLAND CELLS;
D O I
10.1007/BF00374563
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
In the human submandibular ductal cell line (HSG) thapsigargin and carbachol stimulated Ca2+ re lease from the internal Ca2+ pool, resulting in the activation of capacitatively regulated Ca2+ entry (CRCE). This entry pathway was permeant to both Ca2+ and Mn2+, blocked by Ni2+ and insensitive to the muscarinic antagonist, atropine. Carbachol also stimulated an increase in cytosolic [Ca2+] in internal Ca2+-pool-depleted (i.e.thapsigargin-treated) cells which was dependent on the presence of external Ca2+ and blocked by Ni2+, demonstrating that it was due to Ca2+ entry. However, under the same experimental conditions, carbachol was unable to stimulate Mn2+ entry. Additionally, this latter carbachol-stimulated Ca2+ entry pathway was blocked by atropine. Pretreatment of HSG cells with AlF4-, increased basal rates of Mn2+ entry due to CRCE activation, but at tenuated carbachol-stimulated Ca2+ entry into thapsigargin-treated cells. The data suggest that two distinct divalent cation entry pathways are activated in muscarinic-receptor-stimulated HSG cells; a CRCE mechanism, permeable to both Mn2+ and Ca2+, and a second entry mechanism, permeable only to Ca2+. The latter does not depend on internal pool depletion, but appears to be regulated via G-protein activation.
引用
收藏
页码:439 / 445
页数:7
相关论文
共 27 条
[1]   ACTIVATION AND REGULATION OF CALCIUM-ENTRY IN RAT PAROTID-GLAND ACINAR-CELLS [J].
AMBUDKAR, IS ;
HIRAMATSU, Y ;
LOCKWICH, T ;
BAUM, BJ .
CRITICAL REVIEWS IN ORAL BIOLOGY & MEDICINE, 1993, 4 (3-4) :421-425
[2]  
BIRD GS, 1993, J BIOL CHEM, V268, P21486
[3]  
ELY JA, 1991, J BIOL CHEM, V266, P18635
[4]  
FASOLATO C, 1993, J BIOL CHEM, V268, P20737
[5]   MUSCARINIC RECEPTOR-OPERATED CA2+ INFLUX IN TRANSFECTED FIBROBLAST CELLS IS INDEPENDENT OF INOSITOL PHOSPHATES AND RELEASE OF INTRACELLULAR CA2+ [J].
FELDER, CC ;
POULTER, MO ;
WESS, J .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1992, 89 (02) :509-513
[6]   CARBACHOL-ACTIVATED CALCIUM ENTRY INTO HT-29 CELLS IS REGULATED BY BOTH MEMBRANE-POTENTIAL AND CELL-VOLUME [J].
FISCHER, H ;
ILLEK, B ;
NEGULESCU, PA ;
CLAUSS, W ;
MACHEN, TE .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1992, 89 (04) :1438-1442
[7]  
GILMAN AG, 1987, ANNU REV BIOCHEM, V56, P615, DOI 10.1146/annurev.bi.56.070187.003151
[8]  
HE XJ, 1988, BIOCHEM BIOPH RES CO, V152, P1062
[9]   EVIDENCE FOR 2 MODES OF CA-2+ ENTRY FOLLOWING MUSCARINIC STIMULATION OF A HUMAN SALIVARY EPITHELIAL-CELL LINE [J].
HE, XJ ;
WU, XZ ;
TURNER, RJ ;
BAUM, BJ .
JOURNAL OF MEMBRANE BIOLOGY, 1990, 115 (02) :159-166
[10]  
JACONI MEE, 1993, J BIOL CHEM, V268, P26075