Insulin-like growth factor I (IGF-I) has been identified in human seminal plasma. This study was conducted to determine whether IGF-I is present in bovine seminal plasma, whether sperm cells express the IGF-I receptor (IGF-IR), and whether IGF-I affects sperm motility. Semen samples were collected from bulls by electroejaculation and maintained at 37 degrees C, and motility of sperm was assessed. After centrifugation to separate sperm cells from seminal plasma, the seminal plasma was submitted to a validated heterologous RIA for IGF-I. Significant concentrations of IGF-I (116.29 +/- 40.83 ng/ml expressed as mean +/- SD) were measured in bovine seminal plasma. Sperm cells were washed with buffer and subjected to either radioreceptor assay (RRA) or immunocytochemistry (IC). RRA revealed a single high affinity for the IGF-IR with a Kd of 0.83 nM as determined by the computer program LIGAND. IC, using three monoclonal antibodies, localized the IGF-IR to the acrosomal region of the sperm. Computer-assisted sperm-motion analysis was used to determine the effects of IGF-I and IGF-II on bovine sperm motility parameters. Both IGF-I and IGF-II increased sperm motility and straight-line velocity (p < 0.05) relative to the control. The presence of IGF-IR on sperm, the presence of IGF-I in semen, and the ability of IGF-I to stimulate sperm motility provide evidence that the IGF system may be involved in the fertilization process in the bovine species.

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The estrogenic activity of ginseng has been the subject of conflicting reports. Cell proliferation, induction of estrogen-responsive genes, and isolated cases of adverse reactions such as postmenopausal vaginal bleeding and gynecomastia have been reported after ginseng treatment. Other studies report antiproliferative effects with no induction of estrogen-responsive genes. We developed estrogen receptor (ER) alpha and ER alpha competitive binding assays using recombinant receptors and [(3)H]-17 alpha-estradiol to detect phytoestrogens in extracts of Asian ginseng root (Panax ginseng C. A. Meyer) and American ginseng root (Panax quinquefolius L.). Root extracts contained substances that bound both receptor isoforms. These substances had a two to three times greater affinity for ER alpha. Significantly higher binding was found in methanol extracts than in hot water extracts. Subsequent analysis of the extracts revealed significant ER binding attributable to zearalenone, the estrogenic mycotoxin produced by several Fusarium species. The ER showed no binding affinity for Rb1 and Rg1, the major ginsenosides found in P. quinquefolius and P. ginseng, respectively. Thus, ginseng extraction methods, plant species tested, and mycotoxin contaminants may help to explain the disparate literature reports. The prevalence and health significance of fungal contamination in herbal products used for medicinal purposes should be further investigated.

Essential oils obtained by hydrodistillation of female cones (FC), male cones (MC), needle-twigs (NT) and wood-bark (WB) of 'Carolina Sapphire' [Cupressus arizonica var glabra (Sudw.) Little] were analyzed simultaneously by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The main constituents of the investigated essential oils were as follows: FC: -pinene 68.5% and myrcene 11.9%; MC: -pinene 22.5%, epizonarene 9.9%, zonarene 6.9%, limonene 6.8% and cadina-3,5-diene 6.1%; NT: -pinene 20.7%, epi-zonarene 10.4%, zonarene 7.6%, limonene 5.9% umbellulone 5.8% and cadina-3,5-diene 5.8%; WB: -pinene 40.7%, limonene 3.2% and umbellulone 2.9%. Essential oils were evaluated for antifungal activity against the strawberry anthracnose causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. Only WB essential oil showed moderate activity when compared with the commercial antifungal standards. Carolina Sapphire essential oils exhibited biting deterrent activity at 10 µg/cm 2 with Biting Deterrence Index (BDI) values of 0.64, 0.59, 0.65 and 0.72, for FC, MC, NT and WB, respectively, and were significantly lower (P≤0.05) than the synthetic insect repellent, DEET (N,N-diethyl-meta-toluamide), at 25 nmol/cm 2 against Aedes aegypti. The biting deterrence of NT and WB oils at 100 µg/cm 2 with BDI values of 1.04 and 1.01, respectively, were similar, whereas the activity of MC (BDI=0.88) and FC (BDI=0.62) essential oils was lower than DEET at 25 nmol/cm 2. Essential oil from FC with LD 50 of 33.7 ppm was most toxic against 1-day-old Ae. aegypti larvae at 24-h post treatment. Female cone essential oil was significantly more toxic than MC (LD 50 =53.6 ppm), NT (LD 50 =55.5 ppm) and WB (LD 50 =44.6 ppm) essential oils.

We have previously demonstrated the existence of an adenosine 5',5"',P1,P4-tetraphosphate (Ap4A) receptor in mouse hart membrane fractions [Hilderman, R. H., Martin, M., Zimmerman, J. K., & Pivorun, E. P. (1991) J. Biol. Chem. 266, 6915-6918]. However, we did not determine the cellular localization or distribution of the receptor. In this report, the Ap4A receptor is shown to be on the cell surface of individual mouse heart cells by the following four methods: (1) intact cells show specific, saturable, and reversible binding of Ap4A; (2) monoclonal antibodies (Mabs) raised against the Ap4A receptor inhibit Ap4A binding to its receptor on intact heart cells; (3) bound Mabs are shown to be at the outer cell surface via reaction with a alkaline phosphatase conjugated goat anti-rat IgG; (4) when intact cells are labeled with the impermeable cell surface labeling reagent, (sulfosuccinimido) biotin, labeled receptor is immunoprecipitated with Mabs. Furthermore, subcellular fractionation of mouse hearts demonstrates that virtually all of the Ap4A receptor is associated with a membrane fraction with at least 77% of the active receptor on plasma membranes.