Predictors of vitamin D status in New Zealand preschool children.

Vitamin D deficiency has adverse health effects in young children. Our aims were to determine predictors of vitamin D status and then to use these factors to develop a practical tool to predict low 25(OH)D concentrations in preschool New Zealand children. A cross-sectional sample of 1329 children aged 2 to <5 years were enrolled from throughout New Zealand in late-winter to spring 2012. 25-Hydroxyvitamin D (25(OH)D) was measured on dried blood spot (DBS) samples collected using finger-prick sampling. Caregivers completed a questionnaire. Mean (SD) DBS 25(OH)D concentration was 52(19)nmol/L. 25(OH)D < 25 nmol/L was present in 86(7%), 25(OH)D < 50 nmol/L in 642(48%), 25(OH)D 50- < 75 nmol/L in 541(41%) and 25(OH)D > 75 nmol/L in 146(11%) of children. Factors independently associated with the risk of 25(OH)D < 25 nmol/L were female gender (OR 1.92,95%CI 1.17-3.14), other non-European ethnicities (not including Maori or Pacific) (3.51,1.89-6.50), had olive-dark skin colour (4.52,2.22-9.16), did not take vitamin D supplements (2.56,1.06-6.18), had mothers with less than secondary-school qualifications (5.00,2.44-10.21) and lived in more deprived households (1.27,1.06-1.53). Children who drank toddler milk (vitamin D fortified cow's milk formula marketed to young children) had a zero risk of 25(OH)D < 25 nmol/L. The predictive tool identified children at risk of 25(OH)D < 25 nmol/L with sensitivity 42%, specificity 97% and ROC area-under-curve 0.76(95%CI 0.67-0.86, p < 0.001). Predictors of low vitamin D status were consistent with those identified in previous studies of New Zealand children. The tool had insufficient predictive ability for use in clinical situations, and suggests a need to promote safe, inexpensive testing to determine vitamin D status in preschool children.

Inflammatory status modulates plasma lipid and inflammatory marker responses to kiwifruit consumption in hypercholesterolaemic men.

BACKGROUND AND AIMS: Kiwifruit has the potential to improve markers of metabolic dysfunction, but the response may be influenced by inflammatory state. We aimed to investigate whether inflammatory state would modulate the effect of consuming two green kiwifruit daily on plasma lipids and markers of inflammation. METHODS AND RESULTS: Eighty-five hypercholesterolaemic men completed a 4-week healthy diet run-in, before randomisation to a controlled cross-over study of two 4-week interventions of two green kiwifruit/day plus healthy diet (intervention) or healthy diet alone (control). Anthropometric measures and fasting blood samples (plasma lipids, serum apolipoproteins A1 and B, high-sensitivity C-reactive protein (hs-CRP) and interleukin (IL)-6, tumour necrosis factor-alpha (TNF-α) and IL-10) were taken at baseline, 4 and 8 weeks. Subjects were divided into low and medium inflammatory groups, using pre-intervention hs-CRP concentrations (hs-CRP <1 and 1-3 mg/L, respectively). In the medium inflammatory group the kiwifruit intervention resulted in significant improvements in plasma high-density lipoprotein cholesterol (HDL-C) (mean difference 0.08 [95% CI: 0.03, 0.12] mmol/L [P < 0.001]), total cholesterol (TC)/HDL-C ratio (-0.29 [-0.45, -0.14] mmol/L [P = 0.001]), plasma hs-CRP (-22.1 [-33.6, -4.97]% [P = 0.01]) and IL-6 (-43.7 [-63.0, -14.1]% [P = 0.01]) compared to control treatment. No effects were seen in the low inflammatory group. There were significant between inflammation group differences for TC/HDL-C (P = 0.02), triglyceride (TG)/HDL-C (P = 0.05), and plasma IL-6 (P = 0.04). CONCLUSIONS: Inflammatory state modulated responses to the kiwifruit intervention by improving inflammatory markers and lipid profiles in subjects with modestly elevated CRP, suggesting this group may particularly benefit from the regular consumption of green kiwifruit. Registered 16th March 2010, Australian New Zealand Clinical Trials Registry (no. ACTRN12610000213044), www.ANZCTR.org.au.

Body composition of New Zealand-born term babies differs by ethnicity, gestational age and sex.

BACKGROUND: Body composition provides important information on nutrition and future metabolic risk. New Zealand has a diverse ethnic population for which there are no newborn body composition data. AIM: To determine body composition in a cohort of New Zealand-born term babies. STUDY DESIGN: Observational study. SUBJECTS: Healthy, term infants between 37+0 and 41+6 weeks' gestation in two hospitals in Auckland, New Zealand. OUTCOME MEASURES: Body composition by air displacement plethysmography and anthropometry measured within 5 days of birth. Parent-identified ethnicity was prioritised according to Ministry of Health criteria. Data were analysed using t-test, ANOVA with Tukey post-hoc tests, quantile regression and are mean(SD). RESULTS: 440 babies (54% male) were included. Pacific Island/Maori (PI/M) were heavier at birth than Asian/Middle Eastern/Latin American/African (Asian+) babies (3403(506) vs 3181(485) g, p < .05). PI/M and European (E) babies were longer with larger head and waist circumferences than Asian+ babies (all p < .05). Absolute fat mass (FM) was not different amongst ethnicities (E, 365(156), PI/M, 347(183), Asian+, 357(188) g) but PI/M babies had significantly lower FM% than Asian+ (9.8(4.3) vs 10.9(4.5) %, p < .05). Fat-free mass (FFM) was greater in PI/M (3056(400) g) than E (2952(345) g (p < .05) and both PI/M and E had greater FFM than Asian+ (2824(363) g, p < .05). Early term babies had less FFM than term and late-term babies (2732(370), 3012(352), 3173(302)g, p < .001) respectively. CONCLUSIONS: Asian+ babies were the smallest babies with the least FFM yet had similar FM and the highest FM%, indicative of a thin, fat phenotype from birth.

Preferred natural food of breeding Kakapo is a high value source of calcium and vitamin D.

The Kakapo, a large NZ native parrot, is under severe threat of extinction. Kakapo breed only in years when the local podocarps, including rimu (Dacrydium cupressinum), are fruiting heavily, and the fruit are the preferred food both in the diet of breeding females and for provisioning chicks. Attempts to provide a supplementary food during years of poor fruit supply have failed to encourage breeding. Nutrient analysis of rimu berries reveals high calcium content (8.4mg/g dry matter) which would be essential for both egg shell production and the growing skeleton of the chick. Vitamin D is also critical for these processes and for the maintenance of calcium homeostasis, but the source of vitamin D for these nocturnal, ground-dwelling vegetarians is unknown. OBJECTIVE: To examine the vitamin D status of adult Kakapo, and to investigate the possibility that rimu berries provide vitamin D as well as calcium, thus differentiating them from the supplementary foods provided to date. METHOD: Previously collected and frozen serum from 10 adult birds (6 females, 4 males) was assayed for 25(OH)D3 and D2. Two batches of previously frozen rimu berries were analysed for vitamin D3 and D2. RESULTS: Vitamin D status of the 10 adult birds was very low; mean 4.9nmol/l, range 1-14nmol/l 25(OH)D3. No 25(OH)D2 was detected in any of the birds. High levels of D2 and moderate levels of D3 were found in the rimu berries. CONCLUSION: Traditionally it has been considered that the D3 isoform of this endogenously produced secosteroid is produced only in animals. However, D3 has been reported in the leaves of plants of the Solanacae family (tomato, potato, capsicum). The avian vitamin D receptor (VDR) is thought to have a much greater affinity for the D3 form. Therefore if rimu fruit are able to provide breeding Kakapo with D3, and are a plentiful source of calcium, they could be the perfect food package for breeding and nesting birds. Of wider importance, this finding challenges conventional understanding that D3 production is exclusive to animals, and that there are no high concentration food sources of vitamin D.

A comparison of different embalming fluids on the quality of histological preservation in human cadavers.

There are significant problems in obtaining normal human material for histology for teaching or research purposes. This study shows that tissue from cadavers embalmed for teaching can be used for routine histology. Twelve cadavers embalmed with four different formalin-containing embalming fluids were used (n = 3 per fluid): (1) formalin mix (10% formalin); (2) Dunedin mix (an alcohol-based fluid containing phenol); (3) Michigan mix (a water-based fluid); and (4) phenoxyethanol mix (an alcohol-based fluid containing phenoxyethanol). Tissue blocks of liver, heart, kidney, skin and skeletal muscle were taken from each cadaver, paraffin embedded, sectioned and stained with haematoxylin and eosin (H & E), Periodic Acid Schiff (PAS), or Mallory trichrome (Malt). Each section was assigned an overall score based on the histological quality of the cellular components of the tissue. Sections were scored from 1 to 3 (1 = poor, 2 = satisfactory, 3 = good). Satisfactory sections were obtained from all cadavers except those embalmed with the Dunedin mix. The Michigan and phenoxyethanol fluids resulted in consistently good quality sections. No significant differences in tissue morphology were observed between the different stains. The clearest morphology was observed in the skin and skeletal muscle sections, and in tissues embalmed with fluids which do not contain phenol.

The effect of monthly 50,000 IU or 100,000 IU vitamin D supplements on vitamin D status in premenopausal Middle Eastern women living in Auckland.

BACKGROUND/OBJECTIVES: Middle Eastern female immigrants are at an increased risk of vitamin D deficiency and their response to prescribed vitamin D dosages may not be adequate and affected by other factors. The objectives were to determine vitamin D deficiency and its determinants in Middle Eastern women living in Auckland, New Zealand (Part-I), and to determine serum 25-hydroxyvitamin D (serum-25(OH)D) response to two prescribed vitamin D dosages (Part-II) in this population. PARTICIPANTS/METHODS: Women aged ⩾20 (n=43) participated in a cross-sectional pilot study during winter (Part-I). In Part-II, women aged 20-50 years (n=62) participated in a randomised, double-blind placebo-controlled trial consuming monthly either 50,000, 100,000 IU vitamin D3 or placebo for 6 months (winter to summer). RESULTS: All women in Part-I and 60% women in Part-II had serum-25(OH)D<50 nmol/l. Serum-25(OH)D was higher in prescribed vitamin D users than nonusers (P=0.001) and in Iranians than Arab women (P=0.001; Part-I). Mean (s.d.) serum-25(OH)D increased in all groups (time effect, P<0.001) and differed between groups (time × dosage interaction, P<0.001; 50,000 IU: from 44.0±16.0 to 70.0±15.0 nmol/l; 100,000 IU: 48.0±11.0 to 82.0±17.0 nmol/l; placebo: 45.0±18.0 to 54.0±18.0 nmol/l). Only 32% and 67% achieved serum-25(OH)D⩾75 nmol/l with 50,000 and 100,000 IU/month, respectively. Predictors of 6-month change in serum-25(OH)D were dose (B-coefficient±s.e.; 14.1±2.4, P<0.001), baseline serum-25(OH)D (-0.6±0.1, P<0.001) and body fat percentage (-0.7±0.3, P=0.01). CONCLUSIONS: Vitamin D deficiency/insufficiency is highly prevalent in this population. Monthly 100,000 IU vitamin D for 6 months is more effective than 50,000 IU in achieving serum-25(OH)D ⩾75 nmol/l; however, a third of women still did not achieve these levels.

Expression of IGF-I mRNA in the ovine ovary.

IGF-I has been implicated as a local and/or systemic regulator of ovarian function by acting alone or as an amplifier of the actions of gonadotrophins, thereby influencing follicular growth and ovulation. In the sheep it is uncertain as to whether IGF-I can fulfil an autocrine or paracrine role, since mRNA expression and peptide synthesis have not previously been demonstrated. Using in situ hybridization with ovine and human riboprobes, IGF-I mRNA was found in all major steroidogenic cell types of the sheep ovary, namely the granulosa, theca and luteal cells and, to a lesser extent, the stroma. IGF-I mRNA was found to be expressed in the granulosa and thecal cells of early antral follicles and thereafter in these cell types as the follicles increased in diameter. Evidence for IGF-I mRNA expression in preantral follicles could not be demonstrated. No obvious differences in the levels of expression were observed in ovaries recovered during the luteal phase, follicular phase, anoestrus or after exogenous FSH treatment. IGF-I expression was confirmed by Northern blotting and PCR. These findings are consistent with the notion that IGF-I may have an autocrine or paracrine role in enhancing ovarian function in the sheep.

Impairment of protein synthesis in the rat uterus following intrauterine delivery of indomethacin.

When indomethacin was incorporated into a slow-release preparation (initial content 1.6 mg drug) and placed in one horn of the rat uterus, a significant decrease in protein synthesis occurred for this horn in comparison with control animals (as determined by the incorporation of radioactive leucine) at three different times after insertion. Decreases of 20, 21% at the two times of dioestrus and 28% at the time of oestrus selected were determined. No significant reduction in protein synthesis was found for the contralateral horn, although there was a tendency for it to be lowered at the earliest time of examination when two complete oestrous cycles had passed following insertion. Measurement of the uptake of radioactive leucine by the uterine horns showed no change in response to indomethacin delivery compared to the control animals with silastic implants, and suggested that the transport system for this amino acid in cells of the uterine horns was not affected by the drug. It was apparent that in instances when the protein synthesis of the uterine horn was impaired by indomethacin that a decrease in RNA/DNA ratio existed. At the latest time examined, no alteration in DNA content occurred in the indomethacin-influenced horn but there was a significant reduction in RNA content. For a small proportion of the animals with indomethacin-releasing preparations there was a tendency to show a lengthening of the oestrous cycle over the first three cycles following insertion. Whether this was due to a direct effect of indomethacin on the ovaries or an effect caused by decreased concentrations of prostaglandins in the uterus was unknown. 5 These results provide further evidence that non-steroidal anti-inflammatory drugs can interfere with the synthesis of macromolecular substances, and that such changes need to be taken into account when considering the overall effect of these drugs on tissues and organs.

Peripheral plasma progesterone and oestradiol concentrations associated with successful and unsuccessful recovery of uterine embryos in rhesus monkeys with and without intra-uterine devices.

Concentrations of progesterone and oestradiol were measured in peripheral plasma samples collected at the time when the uteri of rhesus monkeys with an intra-uterine device (IUD) and those without an IUD were flushed in attempts to recover uterine embryos. The proportion of successful attempts in IUD-bearing monkeys was much lower than in the non-IUD-bearing animals. Steroid measurements indicated that this reduced success rate was not due to an effect of the IUD on the timing of ovulation within the menstrual cycle or to a steroid-mediated disturbance in the rate of embryo transport to the uterine lumen. Successful embryo recoveries were associated with a higher progesterone concentration, suggesting that one reason for failure was that the attempt had been made too close to ovulation. There was no evidence of any asymmetry between the left or right ovaries in their ovulatory or steroidogenic activity.

Peripheral and ovarian IGF-I concentrations during the ovine oestrous cycle.

IGF-I was measured by RIA in plasma samples collected 8-hourly for 24 days which included two consecutive preovulatory surges of LH. In a separate study, ovarian venous blood was collected from animals undergoing ovariectomy on day 10 of the oestrous cycle, or 36 h later after being treated with prostaglandin with or without steroid-free bovine follicular fluid. Jugular venous blood samples were collected before, during and after surgery. Follicles were dissected from ovaries of these animals and sorted into categories of small, intermediate and large, non-atretic or atretic, and the follicular fluid was pooled and assayed for IGF-I. From another population of ovaries recovered from the slaughterhouse, granulosa, theca and corpora lutea were isolated, homogenized and assayed for IGF-I. Finally ovarian corpora lutea and granulosa cells were each incubated with tritiated amino acids overnight at 37 degrees C. Thereafter the tissues and media were sonicated, IGF-I extracted from the supernatant and tritiated IGF-I precipitated using a specific IGF-I antibody. The absence of any significant change in peripheral IGF-I concentrations following ovariectomy and the finding that the ovarian venous IGF-I concentrations (161 +/- 10 micrograms/l) were not significantly different from levels seen in peripheral blood (157 +/- 10 microgram/l) indicated that the ovary is not a net exporter of IGF-I. However, the ovary does synthesize IGF-I, as evidenced by granulosa and luteal synthesis, but probably not in quantities in excess of that utilized by ovarian tissues per se. Although the plasma IGF-I levels increased around the second preovulatory LH surge, the results overall indicated that the IGF-I concentrations in plasma are not strictly related to any major ovarian event during the oestrous cycle in the sheep. This view is based on the findings that the concentration of IGF-I in follicular fluid was not related to follicular health but correlated with those in peripheral plasma and that the ovarian venous concentrations did not vary between left and right ovaries irrespective of whether the ovaries contained a corpus luteum, dominant follicle or neither. Collectively, these results are consistent with the notion that IGF-I of ovarian origin fulfils an autocrine/paracrine function and does not have an endocrine role. Moreover, the results show that the concentrations of IGF-I in follicular fluid reflect those in peripheral plasma.

Changes in the mouse ovarian surface epithelium with age and ovulation number.

The cell biology of ovarian surface epithelium (OSE) was studied in mice of varying age and lifetime total ovulation number (OV#), to determine the relative importance of these factors in control of OSE proliferation and development of invaginations and cysts. Ovaries from Swiss Webster mice (total OV# median: range [n mice]) were collected at 4 weeks of age (prepubertal; 0[9]), from 3-month virgins (113: 11-235 [55]), from 12-month old breeders (217: 97-386 [21]) and from 8-month virgin mice, housed in split cages alongside a male, to induce continuous oestrous cycles (629: 456-908 [16]). Scanning electron microscopy revealed cuboidal and squamous cells in OSE from all ages. Higher total OV# markedly increased the rate of OSE invagination and layering. Histology showed the incidence of cysts, which had the appearance of benign serous cystadenomata, increased with age rather than total OV#.

Prostaglandin synthesis by isolated cells of rat uterus: production rates, and effects of indomethacin and histamine.

Luminal epithelial and residual cells (mainly of the endometrial stromal tissue) of proestrous rat uteri have been isolated and cultured in defined medium. The prostaglandins produced during a short-term incubation (2 h) in the presence of 10 microM arachidonic acid (to optimize PG production) were determined by direct assay of the culture medium. For the epithelial cells, PGF2 alpha was produced in greatest amounts, followed by 6-keto PGF1 alpha and PGE, while low levels were synthesized by the residual cells. The synthesis of PGF2 alpha by the epithelial cells was inhibited by incorporating indomethacin into the medium and an IC50 value of 2.3 microM was obtained. Incubations performed with histamine in the absence of exogenous arachidonic acid indicated that the pathways for the production of individual prostaglandins were followed to different relative extents, with the production of 6-keto PGF1 alpha being enhanced for both groups of cells when compared to incubations with arachidonic acid.

Prostaglandin production by isolated cells of rat uterus incubated with or without progesterone.

The production of prostaglandins F2 alpha and 6-keto F1 alpha in vitro by the luminal epithelial and the residual (mainly stomal) cells isolated from the uteri of proestrous rats have been measured. The basic procedure involved culturing the cells overnight, washing, and then incubating for 2 h when the amounts of prostaglandins released into the medium were determined by radioimmunoassay. No significant change occurred when the epithelial cells were incubated in the combined presence of arachidonic acid and progesterone for the short-term culture compared to being incubated with arachidonic acid alone. However, when progesterone was incorporated into the medium for the overnight culture, a significant increase occurred in 6-keto PGF1 alpha production by the epithelial cells, without any change in PGF2 alpha, compared to when the cells were incubated overnight in the absence of progesterone. It is suggested that overnight treatment of the epithelial cells with progesterone increases the amount or activity of prostacyclin synthetase, responsible for converting PGH2 endoperoxide to PGI2. Very low levels of prostaglandin production were found for the residual cells.

A study of uterine embryos recovered from rhesus monkeys fitted with intrauterine devices.

Fifteen mature female rhesus monkeys were mated and operated upon to recover preimplantation uterine embryos. This resulted in the recovery of 25 embryos or unfertilized ava in 43 attempts. The same animals were fitted with plastic intrauterine devices (IUDs) and the recovery procedure was repeated. In this series 61 recovery attempts yielded only 10 embryos, 7 of which were sectioned and analyzed by transmission electron microscopy. This approach revealed the ultrastructural details of embryo degeneration and leukocyte association seen in embryos recovered from IUD-bearing animals. Samples of peripheral venous blood were analyzed for levels of ovarian steroids at the time of embryo recovery. The results are discussed in relation to the mechanism of action of IUDs.

Influence of ethylene oxide exposure on the extraction of indomethacin from dimethicone polymeric rods.

Dimethicone polymeric rods were made to contain 0.3, 2.0, or 3.3% by weight of indomethacin. For each different loading of indomethacin, some of the rods were treated with ethylene oxide at 55 degrees for 1 hr, while others were not exposed to the gas. Treated and untreated rods were sliced, placed in ethanol to extract the indomethacin, and the concentrations of indomethacin in the extracts determined by fluorometry and high-performance liquid chromatography (HPLC). After ethylene oxide treatment, the quantity of indomethacin in the extracts was significantly reduced in rods containing 0.3 and 2.0% indomethacin. For the rods containing 3.3% indomethacin, the recovery of the drug from treated rods was not significantly different from those not exposed.

Suppression of leukocytosis by the intrauterine delivery of high doses of indomethacin in the rat.

Studies were undertaken in rats to determine the intrauterine rate of release of high doses of indomethacin incorporated into Silastic rods. It was found that at a 28% w/w loading an 1X0.1 cm rod would exponentially deliver the drug at an average of 35 micrograms/day for the first 2 weeks; by 70 days the rate had declined to 6.5 microgram/day. After being present for 31 days, these types of medicated rods were found to reduce the numbers of luminal leukocytes when compared with the numbers obtained from uterine horns containing plain, non-medicated rods. Despite the reduction in leukocytosis, implantation was prevented by the high dose of indomethacin.

Intrauterine delivery of indomethacin from a silastic device: effect on the preimplantation embryo and implantation.

Plain silastic IUDs and those incorporating 3.3% w/w of indomethacin were fitted into one uterine horn of adult rats. After a period of 3 weeks, animals were mated and studied for the effects these devices had on the preimplantation embryo, Pontamine Blue Reaction and implantation rates. The indomethacin-loaded devices had no observable effect on ovulation, fertilization or ovum transport. In the horns bearing an indomethacin device, the intrauterine degeneration of preimplantation embryos on Day 5 was not as rapid as was found for the horns bearing plain devices. On Day 6 of pregnancy, Pontamine Blue Reaction sites were virtually absent in the horns bearing either type of device, as were the numbers of normal-sized implants on Days 9 or 10. There was a slight increase in the numbers of abnormal, small implants in horns with indomethacin devices.

Effect of indomethacin incorporation on the retention of silastic intrauterine devices in the rat.

In order to observe the effects of indomethacin upon the retention of silastic intrauterine contraceptive devices, rods containing indomethacin at various loadings were inserted unilaterally into adult rats. In other animals, an unmedicated rod was inserted into one uterine horn whilst an indomethacin-loaded rod was fitted to the other horn. Rods were not secured to the uterine wall and the retention of rods in both groups was determined at weekly intervals. The results show an increased retention for animals fitted with indomethacin-loaded rods over a 4-week period. All unmedicated rods, irrespective of whether a contralateral indomethacin rod was present or not, were expelled by 1 week after insertion.

Matrix metalloproteinases and their endogenous inhibitors during the implantation period in the rat uterus.

Rats were studied to determine if matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) were detectable in developing embryonic and uterine tissues during the implantation period; that is, Days 6-8 of pregnancy. Tissue extracts were studied by zymography, reverse zymography and Western blotting. Immunohistochemistry procedures using antibodies against MMPs and TIMPs were applied to tissue sections that passed through implantation sites. The MMP inhibitor, doxycycline, was injected intraluminally into uterine horns of pseudopregnant animals. MMP-2 and -9, and TIMP-2 were detected in gelatin and reverse zymographs, respectively, from extracts of implantation sites on each day studied. Western blots defined bands corresponding to MMP-1, but casein zymographs did not consistently show evidence of extractable MMP-1 or -3. In tissue sections the primary decidual tissue area stained consistently for TIMP-2 and on Days 7 and 8 this area also had positive staining for MMP-1 in close proximity to the implanting embryo. On Day 8 positive staining in the outer stromal tissue was detected using an antibody against MMP-9, and another MMP (possibly MMP-3) was localized exclusively in ectoplacental cone/trophoblastic cells. Intraluminal injection of doxycycline did not significantly prevent the growth of the uterine horns following surgical induction of pseudopregnancy on Day 5. The strong localization of TIMP-2 in the primary decidual tissue is similar to that reported previously for TIMP-3, indicating that these inhibitors have a role in decidualization, including the regulation of trophoblastic invasion.

Localization and synthesis of collagen types III and V during remodelling and decidualization in rat uterus.

Uteri of pregnant rats on Days 6, 7 and 8 of pregnancy were studied to determine the histochemical distribution of collagen types III and V and the incorporation of [3H]glycine into fibrillar collagens during the period of embryonic implantation. Types III and V had a similar distribution in the non-decidual stromal region and muscle layers in implantation sites. They were found to have very low levels in the primary decidual tissue on Day 6 and were not detected in developing decidual tissues on Days 7 or 8. Following injection of labelled glycine, collagen was extracted and the specific activity of the collagens determined by fluorography and 3H incorporated into the collagen bands in the gels. It was found that incorporation of label into both types I and III was similar (33.4+/-12.0 and 31.8+/-18.1 cpm microg-1 collagen respectively) but 3.5 times that of type V (7.7+/-5.3 cpm microg-1). These studies suggest that although fibrillar collagens are metabolized or redistributed in the growing decidual tissue, they are incorporated rapidly into the extracellular matrix during remodelling of the outer stroma and muscle tissues.