Biochemical Society Transactions (2000), Volume 28, part 2 20 Giudice, L. C., de-Zegher, F., Gargosky, zyxwvutsrqp 5. E., Dsupin, B. A,, de-las Fuentes, L., Crystal, R. A., Hintz, R. L. and Rosenfeld, R. G. ( 1995) J. Clin. Endocrinol. Metab. 80, I 548- I555 21 Giudice, L. C.. Martina, N. A,, Crystal, R A,, Tazuke, 5. and Druzin, M. ( 1997) Am. J. Obstet. Gynecol. zyxwvutsrq 176, 75 1-757 22 Westwood, M., Gibson, J. M., Davies, A. J., Young, R. J. and White, A. (I 994) J. Clin. Endocrinol. Metab. zyxwvutsrq 79, 1735- I74 I 23 Westwood, M., Aplin, J. D. and White, A. (I 997) J. Endocrinol. 152, OC29 24 Westwood. M.. White, A. and Aplin. J. D. (I 997) Placenta 18. A59 25 Westwood, M., Gibson, J. M., Aplin, J. D. and White, A. (1998) J. Reprod. Fertil. 21, I8 26 Irwin, J. C. and Giudice. L. C. (I 998) Growth Hormone IGF Res. 8, 2 1-3 I 27 Koistinen, R., Kalkinnen, N., Huhtala, M. L., Seppala, M., Bohn, H. and Rutanen, E. -M. (I 986) Endocrinology (Baltimore) I 18, 1375-1 378 28 Bell, 5. C., Patel. S.. Jackson, J. A. and Waites, G. T. (1988) J. Endocrinol. I 18, 3 17-328 29 DeChiara. T., Efstratiadis,A. and Robertson, E. ( 1990) Nature (London) 345,78-80 30 Liu, J. P., Baker, 1. Perkins, A. S., Robertson, E. J. and Efstratiadis. A. (I 993) Cell 75. 59-72 3 I Baker, J.. Liu, J. -P.. Robertson. E. and Efstratiadis,A. (I 993) Cell 75, 73-82 32 Sciacca, L., Costantino, A., Pandini. G., Mineo, R.. Frasca, F., Scalia, P., Sbraccia, P., Goldfine, I. D., Vigneri, R. and Belfiori. A. ( 1999) Oncogene 18,247 1-2479 33 Brosens, I., Dixon, H. G. and Robertson, W. G. (I 977) Br. J, Obstet. Gynaecol. 84, 656-663 Received 23 July zyxwvut I999 Structure-function relations in the human placenta zyx P. Dockery", J. Berminghamt and D. Jenkins1 *Department of Anatomy, University College Cork Ireland, +Department of Obstetrics and Gynaecology, National Maternity Hospital Dublin, Ireland, and 1 Department of Obstetrics and Gynaecology, University College Cork Ireland Abstract The human haemochorial placenta is a complex and dynamic interface between embryonic and maternal tissues. A myriad array of compounds has been identified at this interface, some of which exert local effects which might be important in maintaining the integrity of the organ. These compounds are diverse in nature and function; they include enzymes, hormones and bioactive peptides. Successful nidation requires the syn- chronization of endometrial maturation and em- bryonic development. The complex nature of this interface requires the application of sound sam- pling strategies. The new stereological methods have thrown fresh light on the growth and dev- elopment of the human placenta. These methods permit the objective, quantitative description of morphology by efficient design-based methods. This approach has permitted a better definition of the functional morphology of the placenta. Ap- plications of these methodologies are providing a spatial and temporal framework on which to lay the new physiological and molecular information. Here we review the essential features of the stereological approach, identify useful structural Key words: confocal microscopy, irnrnunocytochernistry, sampling, stereology. Abbreviations used: EGF. epidermal growth factor; MMP. matrix metalloproteinase. quantities and provide some examples of their application. The problems associated with the quantification of immunocytochemistry are illus- trated with the use of immunoreactivity to insulin-like growth factor I receptor in normal placentae and in pre-eclampsia. Although stereo- logy can provide useful quantitative information about the structure of this dynamic tissue, other anatomical methods that could be applied to better define the relationships between structure and function will be discussed. These include confocal microscopy, to examine the dynamic physiological interactions of the different tissue compartments, and low-temperature electron microscopy tech- niques such as cryosubstitution, to allow better access to the biochemical information resident in the tissue. The complex and dynamic nature of the tissue requires a multidisciplinary approach ; cen- tral to these investigations is a comprehensive understanding of its fine structure. Introduction The human haemochorial placenta is a complex and dynamic interface between embryonic and maternal tissues. A myriad array of compounds has been identified at this interface, some of which exert local effects which might be important in maintaining the integrity of the organ. These compounds are diverse in nature and function and include enzymes, hormones and bioactive peptides 0 2000 Biochemical Society