A daily rhythm in hCG binding to ovarian follicles of the cyclic hamster

Summary On each day of the estrous cycle hCG binding to follicle increased from 09.00 to 21.00 h; then hCG binding was static until 09.00 h of the next day. FSH binding did not exhibit rhythmicity. This pattern of hCG binding may be related to the pulsing of LH on each cycle day.Acknowledgments. This work was supported by grants from NICHD (15 526, KO478) to P.F.T. and Center grant to the Kansas Center of Mental Retardation and Human Development (HD 02528). A. K. was supported in part by the Council for International Exchange of Scholars (Fulbright Foundation).     

In vitro conversion of steroid hormones in bovine ovarian follicles

Summary In bovine ovarian follicles an in vitro conversion of androstenedione and oestrone into oestradiol-17, and of oestradiol-17 into oestrone was observed. There was no in vitro conversion of pregnenolone, progesterone, dehydroepiandrosterone and testosterone.     

Morphology of the intercapsular segment of the oviduct in the golden hamster with special reference to ovumtransit from ruptured follicles to the ampulla

Summary The intercapsular segment of the oviduct in the golden hamster is not a simple duct which has constant outer and inner diameters. After penetrating the bursa ovarica the ICS has a circular constriction and the corresponding oviductal lumen is narrowed.     

Failure of medial forebrain bundle or raphe ablation to alter the daily temperature rhythm of the rat

Summary The data presented in the present study suggest that neither the ascending noradrenergic fibres confined to the MFB nor the serotonergic fibres originating in or passing through the mesencephalic raphe are essential for periodicity in body temperature. Both control and experimental groups, i.e., rats subjected to medial forebrain bundle or raphe ablation presented circadian periodicity in body temperature and neither the phase, amplitude or overall mean of experimentals differed significantly from controls.     

Failure of medial forebrain bundle or raphe ablation to alter the daily temperature rhythm of the rat.

The data presented in the present study suggest that neither the ascending noradrenergic fibres confined to the MFB nor the serotonergic fibres originating in or passing through the mesencephalic raphe are essential for periodicity in body temperature. Both control and experimental groups, i.e., rats subjected to medial forebrain bundle or raphe ablation presented circadian periodicity in body temperature and neither the phase, amplitude or overall mean of experimentals differed significantly from controls.     

Lack of daily rhythm in the release of assembly pheromones by the tickAmblyomma hebraeum (Koch)

Summary Tests conducted under natural light: dark regimes showed that the release of assembly pheromones by fed males ofAmblyomma hebraeum as well as the response of unfed adult ticks to the pheromones were not affected by daily rhythms.     

A simplified assay for cyclic AMP using protein kinase binding

Summary The protein kinase binding assay for cAMP was modified by substitution of adsorption by QAE cellulose for the membrane filtration. This modification obviates the variation of recovery of cAMP with the volume of buffer used to wash the filter. The assay is reproducible and technically simpler than those currently employed.Acknowledgment. This work was partially supported by grants HL-16583 and HL-18827 from the National Heart and Lung Institute.     

Immunization of female rabbits against testosterone stimulates testosterone accumulation by isolated ovarian follicles

Ovarian follicles isolated from female rabbits after active immunization against testosterone-3-oxime bovine serum albumin produced more testosterone than similar follicles from controls.     

Immunization of female rabbits against testosterone stimulates testosterone accumulation by isolated ovarian follicles

Summary Ovarian follicles isolated from female rabbits after active immunization against testosterone-3-oxime bovine serum albumin produced more testosterone than similar follicles from controls.This work was supported by the Medical Research Council of Canada MT 4192.     

The cyclic motor activity of the ovine gut: its reset at a faster rhythm

Summary In adult sheep, the frequency of the migrating motor complexes (MMC) was increased by the duodenal administration of methysergide, but not affected by other 5-HT₁ or 5-HT₂ antagonists. This reset of the MMC pattern at a faster rhythm suggests a selective action on the enteric neuronal serotoninergic mechanism modulating the pacing of the gut cyclic motor activity.     

Abnormal organization of ovarian follicles in the mutantl(1)su(f) mad-ts ofDrosophila melanogaster

Summary The morphology of ovarian follicles in the temperature-sensitive female-sterile mutantl(1)su(f) ^mad-ts has been studied by means of light and electron microscopy. As the follicle cells gradually degenerate at the restrictive temperature (29°C) the follicles become increasingly disorganized with respect to shape and polarity.Acknowledgments. This work was supported by the Deutsche Forschungsgemeinschaft (SFB 46). We wish to thank Mrs R. Koppa for excellent technical assistance and Mrs G. Mahlke for photographic work. We are also indebted to Dr D. Zissler, Dr E. Gateff and Prof. K. Sander for many helpful suggestions.     

Daily variations of the level of neural secretions in Owenia fusiformis. Persistance of a daily rhythm in cultured tissues]

A quantitative study of elementary granules in neuron axons of the nervous chain of Owenia fusiformis (Annelid polychaete) shows that daily variations of the number of secretory granules occur in unamputated animals and in ventral tissue cultures.These variations are correlated with the thythm of the cell cycle.     

A circannual rhythm in bovine pineal serotonin

Summary Bovine pineal serotonin (5-HT) was analyzed at the time of the solstices and equinoxes from December, 1975 until June, 1978. The highest values of 5-HT were detected at the winter solstices and lowest values at the summer solstices of each year examined. The peaks in bovine pineal 5-HT correspond with a lessened fertility in cattle reported during the winter months.Supported by NSF grant PCM 77-05734.The authors wish to thank Roeglein's Provision Company, Beef Processing Division and especially H. Schmidt, Foreman.     

Prostaglandin-like substances in Propionibacterium acnes II. Stimulatory effect on ovarian cyclic AMP.

The prostaglandin-like substances (PLS) from Propionibacterium acnes increased the ovarian tissue levels of cyclic AMP (cAMP) approximately 2-fold. The lipid material extracted from P. acnes thus behaved like PG's of the E-type, and since it is unlikely that other known stimulators of the ovarian cAMP system can be present in the bacterial lipid fraction, these experiments give further evidence in favour of the occurrence of PLS in P. acnes.