Safe, reliable. Research.

PIP: China has a tradition of scientific inquiry and record of success in developing contraceptives. The Chinese government toward the end of the 1970s invested in biomedical research to support its family planning program with the help of the World Health Organization and the United Nations Population Fund. Several family planning research institutes were created. The research agenda is to evaluate the safety and effectiveness of methods already used in China, while developing entirely new methods for men and women to be potentially introduced on a broad scale in the family planning program. Since 1980, China has developed an outstanding infrastructure for research. Both large-scale epidemiological studies and smaller-scale clinical trials to compare Chinese methods with foreign equivalents have been conducted. Studying IUD safety and effectiveness is of particular importance since it is the most common method of family planning in the country. Research on this method prompted the government to stop producing stainless steel rings and instead scale up production of copper devices. Research on developing new methods is also discussed.^ieng

Effect of dibutyryl cyclic AMP and oestradiol on incorporation of [3H]leucine into the proteins of luminal fluid of the rat uterus.

An injection of 12-5 nmol dibutyryl cyclic AMP (dbcAMP) into each uterine horn of ovariectomized rats maintained on progesterone alone, enhanced incorporation of [3H]leucine into uterine luminal proteins. A value of 11-73 X 10(3) c.p.m. [3H]leucine incorporated/rat was found after injection of dbcAMP compared with 3-69 X 10(3) c.p.m./rat after injection of saline. An injection of 1-0 microgram oestradiol, in contrast, gave 58-05 X 10(3) c.p.m./rat. Electrophoretic analysis showed that the radioactively labelled proteins found after an injection of dbcAMP or oestradiol were qualitatively similar to those detected on day 5 of pregnancy, the day of blastocyst implantation. The nucleotide thus apparently elicits a uterine response similar to that observed after an injection of oestradiol.

Cyclic AMP and the preparation of the mouse uterus for implantation.

Experiments are described that demonstrate the ability of dibutyryl cyclic AMP (dcAMP) to induced oestrogen-like changes in the uteri of ovariectomized mice treated with progesterone. A single intraluminal injection of 6-14 micrograms dcAMP in 0-02 ml phosphate-buffered saline promoted cell division in the uterine stroma and sensitized the endometrium so that a decidual reaction could be induced by a subsequent injection of arachis oil into the uterine lumen. Since dcAMP has already been shown to induce implantation of diapausing mouse blastocysts in the absence of oestrogen, it is suggested that cyclic AMP is involved in egg implantation in rodents.

Implantation in ovariectomized mice treated with dibutyryl adenosine 3',5'-monophosphate (dibutyryl cyclic AMP).

Experiments are described that demonstrate that uterine intraluminal injection of a 1-25 mM-solution of dibutyryl cyclic AMP (dcAMP) in phosphate buffered saline (PBS) induced implantation in ovariectomized pregnant mice. Pretreatment with progesterone was essential for this effect. When PBS was injected alone, it did not induce implantation in mice treated with progesterone. Bilateral adrenalectomy had no effect on the ability of dcAMP to substitute for oestradiol, showing that the effect was not due to dcAMP-induced oestrogen synthesis in the adrenal cortex. It is suggested that the dcAMP may act at the level of the uterus, the embryo, or both.