Sexual behavior and serum hormone levels in aging rhesus males: effects of environmental change

Old (N = 9) and middle-aged (N = 9) rhesus males (Macaca mulatta) that were housed in the same type of home cage and the same room for several years were moved to a new location in an adjacent building. Their sexual behavior and hormone levels in the weeks preceding the move were compared to those after the move. The hypothesis that the nonspecific sensory stimulation provided by the move would increase levels of sexual behavior was not supported by the data. To the contrary, the percentages of tests with contacts, mounts, and penile erections, and the rate of contacting the female, decreased significantly for both old and middle-aged males. The intromission rate of middle-aged, but not of old, males also decreased. In consonance with previous findings, middle-aged males displayed significantly higher levels of sexual activity than did old males. The differences were observed both before and after the move. Serum testosterone levels did not differ between middle-aged and old males, and the move did not produce significant changes in testosterone levels. Serum cortisol levels were significantly higher immediately after the move (1 hr) but returned to premove levels the following day.     

Inhibition of Ca2+-induced cytosolic enzyme efflux from skeletal muscle by vitamin E and related compounds.

1. Efflux of an intracellular enzyme (creatine kinase) from normal rat skeletal muscles was induced by treatment with the Ca2+ ionophore A23187. Addition of alpha-tocopherol (230 microM) to the incubation medium was found to significantly diminish this efflux, and this effect was mimicked by alpha-tocopherol acetate, phytol and isophytol, but not by Trolox C (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid). 2. Analysis of muscle cation content has shown that these protective effects of alpha-tocopherol etc. are not due to an inhibition of the Ca2+ accumulating effects of the ionophore. 3. Non-enzymic lipid peroxidation of skeletal-muscle homogenates was found to be inhibited by alpha-tocopherol and Trolox C, partially inhibited by phytol and isophytol, but unaffected by alpha-tocopherol acetate. 4. The activity of lipoxygenase enzymes was partially inhibited by alpha-tocopherol, phytol and isophytol, but not by alpha-tocopherol acetate or Trolox C. 5. Prostaglandin E2 efflux from isolated skeletal muscles was stimulated by treatment with the Ca2+ ionophore, but this was unaffected by alpha-tocopherol treatment.     

Threshold for behavioral response to testosterone in old castrated male rhesus macaques

The sexual behaviors of old, intact (N = 5) and old, castrated (N = 6) rhesus macaque males were compared in six series of pair tests with receptive females. The castrated monkeys were tested when untreated and when given five doses of testosterone propionate (TP; 0.004, 0.016, 0.064, 0.256, and 1.024 mg/kg of body weight) in consecutive months. The serum testosterone (T) level was determined for each male before and after each series of tests. When untreated, none of the castrated males ejaculated, and yawning was significantly less in these monkeys than in intact males-no other behavioral measures differed significantly. Within 2 weeks of daily injections of 0.004 mg of TP/kg, two males ejaculated, and all differences in measures of ejaculation were eliminated. A third male ejaculated after 1 week of treatment with 0.016 mg of TP/kg. Yawning values did not differ during and after treatment with 0.064 mg of TP/kg. Although final mean serum T levels were six times higher in castrated (24.3 ng/ml) than in intact males (4.2 ng/ml), sexual performance levels did not exceed those of intact males.     

Sequence variation in the outer-surface-protein genes of Borrelia burgdorferi

Borrelia burgdorferi is a spirochete pathogen transmitted among warm- blooded hosts by ixodid ticks. Frequency-dependent selection for variant outer-surface proteins might be expected to arise in this species, since rare variants are more likely to avoid immune surveillance in previously infected hosts. We sequenced the OspA and OspB genes of nine North American strains and compared them with nine strains previously described. For each gene, the mean number of synonymous substitutions per synonymous site and the mean number of nonsynonymous substitutions per nonsynonymous site show only a twofold excess of silent mutations. Synonymous rates vary widely along the OspB protein. Some regions show a significant excess of silent substitutions, while divergence in other regions is constrained by biased base composition or selection. The presence, in antigenically important regions of the protein, of significant variation among strains, as well as evidence for recombination among strains, should be considered in attempts to develop vaccines against this disease.      

Characterisation of a 34 kD protein from potato cyst nematodes, using monoclonal antibodies with potential for species diagnosis

Two monoclonal antibodies, which differentially recognise the two species of potato cyst nematodes (PCN), Globodera pallida and G. rostochiensis, are described. They have been shown to have potential for quantification of these two species, recognising proteins of the same molecular weight (34 kD) in both species. Further investigation showed these proteins to have isoelectric points at pH values of 5.7 in G. pallida and 5.9 in G. rostochiensis, in common with the proteins used by Fleming & Marks (1983) to differentiate the species of PCN. They are likely to be structurally very similar, with the same physiological function (and therefore similar concentrations) in the two species. In cross-reactivity tests with a wide range of soil nematode species, the antibodies reacted strongly only with species of the genus Globodera, and thereby confirmed their potential as the basis of a quantitative immunoassay likely to be useful in management of PCN populations.     

Gap junction structures: Analysis of the x-ray diffraction data

Models for the spatial distribution of protein, lipid and water in gap junction structures have been constructed from the results of the analysis of X-ray diffraction data described here and the electron microscope and chemical data presented in the preceding paper (Caspar, D. L. D., D. A. Goodenough, L. Makowski, and W.C. Phillips. 1977. 74:605-628). The continuous intensity distribution on the meridian of the X-ray diffraction pattern was measured, and corrected for the effects of the partially ordered stacking and partial orientation of the junctions in the X-ray specimens. The electron density distribution in the direction perpendicular to the plane of the junction was calculated from the meridional intensity data. Determination of the interference function for the stacking of the junctions improved the accuracy of the electron density profile. The pair-correlation function, which provides information about the packing of junctions in the specimen, was calculated from the interference function. The intensities of the hexagonal lattice reflections on the equator of the X-ray pattern were used in coordination with the electron microscope data to calculate to the two-dimensional electron density projection onto the plane of the membrane. Differences in the structure of the connexons as seen in the meridional profile and equatorial projections were shown to be correlated to changes in lattice constant. The parts of the junction structure which are variable have been distinguished from the invariant parts by comparison of the X-ray data from different specimens. The combination of these results with electron microscope and chemical data provides low resolution three- dimensional representations of the structures of gap junctions.     

Diurnal patterns of testosterone, dihydrotestosterone, estradiol, and cortisol in serum of rhesus males: Relationship to sexual behavior in aging males

This study was carried out to determine differences between old and young rhesus males in levels and diurnal patterns of testosterone, dihydrotestosterone, cortisol, and estradiol, and to determine correlations between these hormones and sexual behavior of the old males. Blood was drawn from old (n = 9) and young (n = 9) rhesus males over 5 consecutive days at 0900, 1300, and 2100 hr. The two groups of males did not differ in mean serum levels of testosterone, dihydrotestosterone, or estradiol at any time. Although the old and young did not differ in cortisol levels at 0900 and 1300 hr, the cortisol levels at 2100 hr were lower in the old males. Diurnal variations in testosterone, dihydrotestosterone, and cortisol were comparable in old and young males. Mean serum levels of estradiol were significantly higher at 0900 hr than at 1300 hr in the old males, whereas in the young males estradiol levels did not differ with time of day. There was a significant positive correlation between testosterone and yawning rate, and cortisol levels were correlated positively with rate of contacting, rate of mounting, and percentage of tests with erections. The decline in sexual performance of old rhesus males cannot be attributed to changes in the levels or diurnal patterns of testosterone, dihydrotestosterone, or estradiol, but lower cortisol levels in old males may contribute to the decline in sexual behavior.     

Sexual behavior of laboratory- and wild-born male Rhesus monkeys.

Rearing method has an important influence on the sexual performance of adult male rhesus monkeys. Testosterone levels and sexual behavior of laboratory-born and -reared adult males were compared with those of males born in the wild and brought to the laboratory as adults. The mean sexual performance level of colony-reared animals was significantly below that of males born in the wild but testosterone levels in the two groups did not differ significantly. Not all laboratory-reared males were sexually inadequate but less than 30% ejaculated in tests of sexual behavior. The sexual behavior and testosterone levels of adult males treated prenatally with testosterone propionate were found not to differ from those of untreated males reared in the same way. Conclusions about sexual adequacy based on 10-mm tests of sexual behavior differed very little from those based on 1-hr tests.     

甘肃省被子植物分布新记录

报道了甘肃省分布的玄参科(Scrophulariaceae)水茫草属(Limosella Linn.)1个新记录属,以及玄参科(Scrophulariaceae)、木兰科(Magnoliaceae)、蓼科(Polygonaceae)、胡颓子科(Elaeagnaceae)、百合科(Liliaceae)5个新记录种——水茫草(Limosella aquatica Linn.)、峨眉含笑(Michelia wilsonii Finet et Gagnep.)、叉分蓼(Polygonum divaricatum L.)、棱果沙棘(Hippophae goniocarpa Y.S.Lian et al.ex SwensonBartish)、青海黄精(Polygontum qinghaiense Z.L.Wu et Y.C.Yang)。其中,峨眉含笑是国家二级重点保护野生植物。