Finger-prick--an alternative to venipuncture for the assessment of endocrine profiles in women.

Traditionally, there has been a reliance on venipuncture to obtain peripheral blood endocrine levels for the assessment of infertility treatment cycles. We have assessed the viability of a finger-prick capillary blood collection method to provide an alternative to venipuncture, assisting in the treatment of patients for whom venous sampling may be difficult to perform. A direct one-to-one relationship was found between the two collection methods with respect to E2, P, and LH measurement. Finger-prick blood collection is simple and easy to perform and provides a viable alternative to venipuncture. It also alleviates the stress involved with multiple attempts at venous sampling in some patients.

Prostaglandin F2 alpha mediates platelet-activating factor-stimulated atrial natriuretic factor release from the isolated rat heart.

Platelet-activating factor (PAF) and the prostaglandins have recently been shown to stimulate atrial natriuretic factor (ANF) secretion from the heart. As PAF also potentiates the release of cyclooxygenase products from isolated hearts, the role of these substances in PAF-induced ANF secretion was investigated. Using an isolated perfused rat heart preparation, cyclooxygenase inhibition by indomethacin or meclofenamic acid (10 microM for each) significantly attenuated the rise in ANF associated with PAF administration (2.5 nmol). Prostaglandin F2 alpha (PGF) produced an immediate and dose-dependent increase in ANF secretion, which was significant at 0.01 mumol and reached 348 +/- 66% over baseline values after a 1-mumol injection. Prostaglandin E2 (PGE) generated a much smaller 98 +/- 25% increase after a 1-mumol administration. Furthermore, PGF but not PGE was released from isolated hearts immediately after PAF administration. PGF release reached a maximum of 0.06 nmol/min g Heart-1 1 min after PAF stimulation and had returned to undetectable baseline values by 6 min. Cyclooxygenase inhibition abolished the release of PGF after PAF, in addition to attenuating (by 60-70%) the increased secretion of ANF after PAF injection. These results demonstrate very clearly that PGF is the major mediator for PAF-stimulated ANF secretion. Such an interaction may provide an alternative mechanism to atrial distension for the secretion of ANF in pathologies such as myocardial infarction, where autacoids such as PAF and the PGs are released from damaged cardiac muscle and elevated plasma levels of ANF are observed.

Inhibin and relaxin concentrations in early singleton, multiple, and failing pregnancy: relationship to gonadotropin and steroid profiles.

OBJECTIVE: To examine the inter-relationships between inhibin, relaxin, steroid concentrations, estradiol (E2), progesterone (P), and gonadotropins in early pregnancy. DESIGN: Hormone concentrations in plasma were measured during the luteal phase of subjects who became pregnant (n = 58) or failed to become pregnant (n = 47) after ovarian hyperstimulation for in vitro fertilization-gamete intrafallopian transfer (IVF-GIFT) (group 1). A further group of subjects became pregnant (n = 7) or failed to become pregnant (n = 8) during endocrinology tracking of a natural cycle (group 2). Blood was obtained every 3 days in the luteal phase from day 5 in group I (day 0 was oocyte recovery) and from day 0 (first increase in luteinizing hormone [LH]) in group II. RESULTS: Progesterone and E2 were increased over nonpregnant values by day 11 (P) and day 16 (E2) in group I and by day 11 (E2 and P) in group II. Inhibin and relaxin concentrations were significantly increased by day 16 in group I (often by day 11) and by day 14 in group II pregnancy subjects. A direct relationship existed between inhibin, P, relaxin, and human chorionic gonadotropin (hCG). Subjects who had twin pregnancies demonstrated higher concentrations of all hormones and often exhibited increases earlier (by day 11 in group I) than singleton pregnancy subjects. Pregnancies that ended in miscarriages tended to have lower concentrations of P and inhibin. None of the hormones reliably discriminated between the clinical conditions of blighted ovum and of spontaneous abortion, and the predictive value of any hormone measured for miscarriage was not high. CONCLUSIONS: The trend of inhibin and relaxin concentrations closely parallels rises in P during early pregnancy. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels are suppressed very early in pregnancy. The suppression of LH and FSH in hyperstimulated cycles is more governed by E2 than inhibin in stimulated cycles. Some subjects destined to miscarry exhibit abnormal endocrine changes very early in the luteal phase.

Simple quantitative measurement of serum choriogonadotropin compared with immunoradiometric, immunoenzymometric, and chemiluminescent assays.

We evaluated a new simplified quantitative method (Tandem Icon QSR; Hybritech) for choriogonadotropin (hCG), which could theoretically be performed in a ward or with outpatients. The method was compared with immunoradiometric (Bioclone Australia), chemiluminescent (Amerlite; Amersham), and immunoenzymometric assays (Stratus; Dade). We analyzed by each of the methods 104 serum samples from pregnant and nonpregnant patients. For quantitative hCG values indicative of pregnancy (greater than 25 int. units/L), excellent correlation was observed between the Tandem Icon method and the other standard laboratory assays (r = 0.995, 0.990, and 0.992, respectively). Occasional problems arose because of the instability of Tandem Icon QSR reagents at room temperature but this was resolved by storing the reagents at 4 degrees C. We conclude that this simplified quantitative method for hCG is reliable and suitable for use outside of the routine immunoassay laboratory.