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71.
Interstrain Variation in Amylase Gene Copy Number and mRNA Abundance in Three Mouse Tissues 总被引:2,自引:0,他引:2
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Miriam H. Meisler Tammy K. Antonucci Laurelee O. Treisman Deborah L. Gumucio Linda C. Samuelson 《Genetics》1986,113(3):713-722
Amylase expression in strain YBR differs in several respects from the standard mouse phenotype. The synthesis of salivary amylase is elevated twofold in YBR mice and the synthesis of pancreatic amylase is reduced to one-half the normal rate. We have compared the concentrations of amylase mRNA in the parotid, liver and pancreas of YBR mice with those in strains A/J and C3H. We observed differences in amylase mRNA abundance which can account for the levels of amylase protein synthesis in the parotid and pancreas of these strains. Unexpectedly, the concentration of amylase mRNA in the liver of YBR mice was also higher than in the other strains. Since liver amylase is transcribed from the same gene as parotid amylase, duplication of the Amy-1 locus could account for the elevated mRNA concentration in both tissues. Quantitative analysis of genomic DNA by Southern blotting provided direct evidence for duplication of Amy-1 in strain YBR. 相似文献
72.
Seasonal variations in levels of serum testosterone, dihydrotestosterone (DHT), reproductive behavior, and social behavior were investigated in 12 adult males (5 to 20 + years of age) of the Oregon troop of Japanese macaques (Macaca fuscata). Blood samples were collected at 2- to 4-month intervals, and behaviors were monitored twice weekly over a 15-month period. Significant seasonal variations in levels of testosterone and DHT, and in frequencies of mount series, ejaculations, number of female partners, displays, courtship, and aggression were observed. Seasonal variations in reproductive and social behaviors did not correlate with seasonal variations in androgen levels because seasonal increases in these behaviors followed seasonal increases in the androgens with a 1- to 2-month delay. However, significant correlations between increased androgen levels and the onset of mating activity occur when mean monthly frequencies of mount series are shifted 1 to 2 months earlier to coincide with the rise in serum androgen levels. The frequency of adult male play and male-male mounting increased significantly when androgen levels were low. We suggest that photoperiod changes may function as a proximate cue in male Japanese macaques which induces a state of biological readiness for mating, and the behavioral consequences (i.e., mating) are then dependent upon the presence of receptive females. 相似文献
73.
k-Binding and Degradation of [3 H]Dynorphin A (1–8) and [3 H]Dynorphin A (1–9) in Suspensions of Guinea Pig Brain Membranes 总被引:3,自引:0,他引:3
Maureen G. C. Gillan Linda E. Robson Alexander T. McKnight Hans W. Kosterlitz 《Journal of neurochemistry》1985,45(4):1034-1042
Following incubation of [3H]dynorphin A (1-8) and [3H]dynorphin A (1-9) with suspensions of guinea pig brain membranes, analysis of the supernatants by HPLC has shown that both peptides are degraded at 25 degrees C and at 0 degrees C. Bestatin and captopril reduce degradation at 0 degrees C but for a similar degree of protection at 25 degrees C arginine-containing dipeptides are also required. The effects of these peptidase inhibitors on the degradation profiles indicate that [3H]dynorphin A (1-8) has three main sites of cleavage: the Tyr1-Gly2, Arg6-Arg7, and Leu5-Arg6 bonds. With [3H]dynorphin A (1-9) as substrate the Arg7-Ile8 and Ile8-Arg9 bonds are also liable to cleavage. In binding assays, in contrast to the effects of peptidase inhibitors on the degradation of unbound [3H]dynorphin A (1-8) and [3H]dynorphin A (1-9), bestatin and captopril have little effect on the binding characteristics of the tritiated dynorphin A fragments at the kappa-site at 0 degrees C. However, at 25 degrees C binding is low in the absence of peptidase inhibitors. When binding at mu- and delta-sites is prevented, the maximal binding capacities of [3H]dynorphin A (1-8), [3H]dynorphin A (1-9), and [3H](-)-bremazocine at the kappa-site are similar; [3H]dynorphin A (1-9) has 5-10 times higher affinity for the kappa-site than [3H]dynorphin A (1-8). Comparison of the effects of peptidase inhibitors on unbound dynorphin A fragments with their effects in binding assays suggests that the bound peptides are protected from the action of peptidases. 相似文献
74.
Linda Strause Jack Hegenauer Daniel Burstein Paul Saltman 《Biological trace element research》1985,7(2):75-81
The metabolism of orally administered radiomanganese was studied in mice. Assimilation of absorbed manganese (Mn) was determined using whole body counting techniques. When54MnCl2 was administered, 2.7% of the dose was retained after 10 d compared with 1.2% from the54Mn-nitrilotriacetate (NTA) complex. However, this difference was accounted for by the rapid and persistent adsorption of the Mn onto the teeth of the lower jaw when fed as the ionic salt at pH 2.0 compared with the NTA-chelate fed at pH 9.0. Once corrected for the amount adsorbed onto the teeth, the biodistribution and relative specific activity of the assimilated radiomanganese into a variety of tissues were similar for both forms of the metal. 相似文献
75.
76.
A method is described for the extraction of enkephalin-like peptides from peripheral nerve using chloroform and acidic methanol to facilitate a differential extraction of peptides and lipid. Porcine splanchnic nerve contains enkephalin-like peptides in low amounts compared to porcine adrenal medulla and striatum. Gel filtration chromatography reveals the presence of enkephalin-like peptides in both processed and cryptic forms. This is the first reported isolation and partial characterization of these peptides in splanchnic nerve. The presence of these peptides in this nerve provides support for the contention that the splanchnic nerve can modulate catecholamine release from the adrenal medulla through an effect on opiate receptors located on chromaffin cells. 相似文献
77.
G. Gray Eaton Deanne F. Johnson Barbara B. Glick Julie M. Worlein 《Primates; journal of primatology》1986,27(2):141-150
We have quantitatively documented the development of sex differences in the behavior of juvenile Japanese macaques (1 to 2
years of age). Mothers treated their offspring differently by sex, i.e., mothers of males broke contact with them more frequently
than did mothers of females. Juvenile males played more, and mounted other macaques more frequently; juvenile females groomed
their mothers more and were also punished by other group members more frequently than were males. Males showed a pattern of
decreasing interactions with their mothers, but females increased the frequency of their maternal interactions. These patterns
appear to presage the life histories of the sexes. However, comparisons with other species of nonhuman primates indicate that
although sex differences in behavior are common, the variability among species severely limits cross-specific generalizations. 相似文献
78.
79.
Barbara Beckerman Glide G. Gray Eaton Deanne F. Johnson Julie Worlein 《International journal of primatology》1986,7(2):139-155
The behavioral interactions of 22 infant and mother Japanese macaques with other group members were studied. Focal-animal
observations were made from the time of each infant’s birth until 1 year of age. Infants and mothers both displayed exceedingly
strong preferences for associating with matrilineal kin and, specifically, for female kin. The degree of genetic relatedness
was positively correlated with levels of spatial proximity, contact, grooming, aggression, and play. Overall frequencies of
interactions with nonkin were very low, and partner sex was not an important factor in interactions with nonkin. There were
no significant differences between male and female infants in interactions with kin versus nonkin. There was only one significant
difference between male and female infants in interactions with males versus females: female infants showed stronger preferences
for initiating proximity with females over males than did male infants. Because mothers provide the focal point for infant
interactions during the first year of life, we compared the behavior of infants and mothers. Mothers were the recipients of
more social interactions than were infants, mothers engaged in more grooming than did infants, and infants engaged in more
social play than did mothers. These findings are only partially consistent with kin-selection theory, and the inadequacies
of studying matrilineal kin discrimination to test kin selection are reviewed. The near-absence of infant sex differences
in associations with social partners suggests that although maternal kin other than the mother are important to infant socialization,
they probably do not contribute to the development of behavioral sex differences until after the first year of life. 相似文献
80.
Glick Barbara Beckerman Eaton G. Gray Johnson Deanne F. Worlein Julie M. 《International journal of primatology》1986,7(5):467-479
Quantitative data are presented on the effects of subject sex, partner sex,and kinship on the social interactions of 18 juveniles of the Oregon troop of Japanese macaques (Macaca fuscata).Data on these subjects as infants were also used to detail maturational changes in partner sex preferences. Nine males and
nine females, whose multiparous mothers represented a cross section of dominance ranks, were observed using a focal-animal
technique. Juveniles of both sexes engaged in more proximity, contact, grooming, mounting, aggression, and social play with
kin than with nonkin partners. They initiated less contact with females and more contact with males during their second year.
They initiated more grooming and aggression during their second year than their first year, with females displaying a strong
preference for grooming females and males specifically aggressing males more during the second year. Aggression was higher
between same-sexed partners than between opposite-sexed partners. Males engaged in more social interactions with males during
the second year than the first year of life. Males played more than females during both years. Males played more with males
during the second year than the first year, and males played with males more than did females during the second year. We conclude
that sex differences in behavioral frequencies become evident during the first year of life, and sex differences in partner
preferences emerge during the second year of life. 相似文献