The macrophage nature of renin-positive cells in human decidua

149 RELATIONSHIP OF TISSUE RENIN AND FOLLICULARSIZE WITH ANGIOTENSIN II RECF-.rIDR DENSITY IN BOVINE OVARIANFOLLICLES. A H. Nmlsen, A Hagemann, B. Svenstrup', J. Nielsen" and K Poulsen, Department of Anatomy and Physiology, The Royal Vetennary and Agricultural Umvers]ty, DK-1870 Fredenksberg C and "Department of Climcal B]ocbemlstry, Statens Serummstltut, DK-2300 Kobenhavn S, Denmark. The purpose was to investigate anglotensm (Ang) II receptors m isolated bovine ovarian folhcles and the relationship of their density to folhcular concentraUons of prorenm, active renm, oestradiol, and progesterone. Displacement of 125I-[Sarl-IleLI1eS]-Ang II binding by the Ang II receptor antagomsts PD 123319 and Losartan confirmed that folhcular Ang II receptors are of subtype 2 (AT2 receptor). The dlssociatmn constant (Kd) for [lleS]-Ang II (human Ang II) was 0 84 (range 0 51 - 1.47) nmol/l The receptor density vaned between 90 and 5990 (mean 1640) fmol/mg membrane protein. The follicular Ang II receptor density correlated positively with follicular diameter (Spearman's rho = 0.518, p<0.003) and tissue weight (Spearman's rho = 0 636; p<0.0001), and negatively with the active renm concentration m the folhcular wall (Spearman's rho = -0.399; p<0.02). The Ang II receptor density did not correlate with the follicular fluid concentrations of proremn, active renm, oestradml (E2), progesterone (I'4) or the F.2/P4 ratio. The reverse relationship between Ang II receptor density and the high acuve renm concentrations in the folhcular wall suggests an actavc regulated tissue renm-ang]otensm system A high Ang II receptor density ~s a general feature of large bowne ovarian folhcles THE MACROPHAGE NATURE OF RENIN-POSITIVE CELLS IN HUMAN DECIDUA M Hanssens, L Vercruysse, L Verblst, R Pqnenborg, M J N C Keirse, and F A Van Assche, Dept of Obstet and Gynaecol Umvers~ty of Leuven, Belgium Renin positive cells are dispersed In the decldua basahs underlying the placenta, the decldua vera, and the decldua capsulans adhering to the chorion laeve of term human pregnancy (M Hanssens et al, 9th Sc, Meet,ng of Am Soc. Hypert e n s . abstract L9, 1994) These cells have many characteristics of macrophages they are small mfdtrating cells with variable size and shape, and some are Ioaden with haemos~derm Double staining for renin and a cytoplasmatlc macrophage marker CD69, was achieved by combining the APAAP technique using an anti-human renin monoclonal F37 1A1/Sera-Lab w~th the peroxldase hnked direct immunotechnique for CD68 of Dako-Epos kit Alkahne phosphatase was detected m blue using N-ASMX-P/FastBlueBB, while peroxidase was detected in red-brown with HzOz/AEC. With this technique renm positive staining was demonstrated within CD68 positive cells The presence of renm in macrophages can explain existing controversies derived from renin measurements m t,ssue extracts and culture media The presence of renm positive macrophages in arterial segments undergoing damage (acute atherosis} or tissue repair (int=mal thickening) could sustain a heahng function of macrophage renm-anglotensm within the uteroplacental unit