TY - JOUR
T1 - The lipid integrity of membranes of guinea pig alveolar macrophages studied by nanosecond fluorescence decay of 1,6-diphenyl-1,3,5-hexatriene
T2 - The effect of stimulation by concanavalin A and formyl peptides1
AU - Cherenkevich, S. N.
AU - Vanderkooi, J. M.
AU - Restifo, R.
AU - Daniele, R. P.
AU - Holian, A.
N1 - Funding Information:
’ A. H. was supported by New Investigator Grant HL 26266, J.M.V. by GM 12202 from NIH. ’ Abbreviations used: DPH, 1,6-diphenyl-1,3,5-hexatriene; FMP, N-formylmethionylphenylalanine;
PY - 1982/3
Y1 - 1982/3
N2 - Time-resolved fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene was used to monitor physical changes in the membranes of guinea pig alveolar macrophages following stimulation by N-formyl peptides (either N-formylmethionylphenylalanine (FMP) or N-formyl methionyl leucylphenylalanine (FMLP)) and concanavalin A. The anisotropy of diphenylhexatriene in macrophages showed a dependence on stimulation both in the rate of decay and in the value of anisotropy at infinite time. Subtle differences were observed between the effect of concanavalin A and FMLP on the membrane lipid fluidity as detected by fluorescence anisotropy. Concanavalin A stimulation of macrophages decreased the value of the anisotropy at infinite times in the range of 0-20 °C and increased the value at 25-40 °C; and at all temperatures it decreased the rate of decay of anisotropy. At temperatures below 25 °C, the response to FMLP was similar to concanavalin A, but above 25 °C, FMLP only slightly modified the anisotropy decay profile. Another physical parameter, calcium permeability, was examined because Ca+2 fluxes are dependent upon membrane properties. The temperature-dependent profiles of concanavalin A and FMP-stimulated 45Ca+2 efflux from alveolar macrophages were similar. The rate and extent of 45Ca+2 efflux increased from 4 to 22 °C, with no further increases observed up to 37 °C. This pattern correlated well with observed changes in membrane fluidity.
AB - Time-resolved fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene was used to monitor physical changes in the membranes of guinea pig alveolar macrophages following stimulation by N-formyl peptides (either N-formylmethionylphenylalanine (FMP) or N-formyl methionyl leucylphenylalanine (FMLP)) and concanavalin A. The anisotropy of diphenylhexatriene in macrophages showed a dependence on stimulation both in the rate of decay and in the value of anisotropy at infinite time. Subtle differences were observed between the effect of concanavalin A and FMLP on the membrane lipid fluidity as detected by fluorescence anisotropy. Concanavalin A stimulation of macrophages decreased the value of the anisotropy at infinite times in the range of 0-20 °C and increased the value at 25-40 °C; and at all temperatures it decreased the rate of decay of anisotropy. At temperatures below 25 °C, the response to FMLP was similar to concanavalin A, but above 25 °C, FMLP only slightly modified the anisotropy decay profile. Another physical parameter, calcium permeability, was examined because Ca+2 fluxes are dependent upon membrane properties. The temperature-dependent profiles of concanavalin A and FMP-stimulated 45Ca+2 efflux from alveolar macrophages were similar. The rate and extent of 45Ca+2 efflux increased from 4 to 22 °C, with no further increases observed up to 37 °C. This pattern correlated well with observed changes in membrane fluidity.
UR - http://www.scopus.com/inward/record.url?scp=0020026830&partnerID=8YFLogxK
U2 - 10.1016/0003-9861(82)90034-0
DO - 10.1016/0003-9861(82)90034-0
M3 - Article
C2 - 7082003
AN - SCOPUS:0020026830
SN - 0003-9861
VL - 214
SP - 299
EP - 304
JO - Archives of Biochemistry and Biophysics
JF - Archives of Biochemistry and Biophysics
IS - 1
ER -