Predator-induced opioid and non-opioid mediated analgesia in young meadow voles: sex differences and developmental changes

BackgroundTwin and family studies using Western samples have established that child and adolescent anxiety and depression are under substantial genetic, modest shared environmental, and substantial non-shared environmental influences. Generalizability of these findings to non-Western societies remains largely unknown, particularly regarding the changes of genetic and environmental influences with age. The current study examined changes in genetic and environmental influences on self-reported anxiety and depression from late childhood to mid-adolescence among a Chinese twin sample. Sex differences were also examined.MethodSelf-reported anxiety and depression were collected from 712 10- to 12-year-old Chinese twins (mean = 10.88 years, 49% males) and again 3 years later. Quantitative genetic modeling was used to examine developmental changes in genetic and environmental influences on anxiety and depression, and sex differences.ResultsHeritability of anxiety and depression in late childhood (23 and 20%) decreased to negligible in mid-adolescence, while shared environmental influences increased (20 and 27% to 57 and 60%). Shared environmental factors explained most of the continuity of anxiety and depression (75 and 77%). Non-shared environmental factors were largely time-specific. No sex differences were observed.ConclusionsShared environmental influences might be more pronounced during the transition period of adolescence in non-Western societies such as China. Future research should examine similarities and differences in the genetic and environmental etiologies of child and adolescent internalizing and other psychopathology in development between Western and non-Western societies.

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Sex differences in spontaneous locomotor activity and rotational behavior in meadow voles

Physiology & Behavior ◽

10.1016/s0031-9384(98)00111-5 ◽

1998 ◽

Vol 65 (2) ◽

pp. 387-391 ◽

Cited By ~ 5

Author(s):

C Marczinski ◽

T.S Perrot-Sinal ◽

M Kavaliers ◽

K.-P Ossenkopp

Keyword(s):

Sex Differences ◽

Locomotor Activity ◽

Spontaneous Locomotor Activity ◽

Rotational Behavior ◽

Meadow Voles

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Sex differences in estimated brain metabolism in relation to body growth through adolescence

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x17737692 ◽

2017 ◽

Vol 39 (3) ◽

pp. 524-535 ◽

Cited By ~ 3

Author(s):

Simon N Vandekar ◽

Haochang Shou ◽

Theodore D Satterthwaite ◽

Russell T Shinohara ◽

Alison K Merikangas ◽

...

Keyword(s):

Sex Differences ◽

Brain Metabolism ◽

Nonlinear Models ◽

Body Growth ◽

Developmental Changes ◽

Cross Sectional ◽

Age Related ◽

Positron Emission ◽

Developmental Age ◽

Maximum Body

The human brain consumes a disproportionate amount of the body’s overall metabolic resources, and evidence suggests that brain and body may compete for substrate during development. Using perfusion MRI from a large cross-sectional cohort, we examined developmental changes of MRI-derived estimates of brain metabolism, in relation to weight change. Nonlinear models demonstrated that, in childhood, changes in body weight were inversely related to developmental age-related changes in brain metabolism. This inverse relationship persisted through early adolescence, after which body and brain metabolism began to decline. Females achieved maximum body growth approximately two years earlier than males, with a correspondingly earlier stabilization of brain metabolism to adult levels. These findings confirm prior findings with positron emission tomography performed in a much smaller cohort, demonstrate that relative brain metabolism can be inferred from noninvasive MRI data, and extend observations on the associations between body growth and brain metabolism to sex differences through adolescence.

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Male and female meadow voles Microtus pennsylvanicus respond differently to scent marks from the top- middle-, and bottom-scent donors of an over-mark

Current Zoology ◽

10.1093/czoolo/57.4.441 ◽

2011 ◽

Vol 57 (4) ◽

pp. 441-448 ◽

Cited By ~ 6

Author(s):

Michael H. Ferkin ◽

Nicholas J. Hobbs ◽

Benjamin D. Ferkin ◽

Adam C. Ferkin ◽

Daniel A. Ferkin

Keyword(s):

Sex Differences ◽

Microtus Pennsylvanicus ◽

Receptive Female ◽

Scent Mark ◽

Same Sex ◽

Scent Marks ◽

Meadow Voles ◽

Male And Female ◽

Terrestrial Mammals

Abstract Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bottom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bottom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks.

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Developmental Changes in Self-Perceptions of Intelligence and Self-Confidence

Psychology of Women Quarterly ◽

10.1111/j.1471-6402.1980.tb00959.x ◽

1980 ◽

Vol 5 (2) ◽

pp. 231-239 ◽

Cited By ~ 11

Author(s):

Alice Ross Gold ◽

Lorelei R. Brush ◽

Eve R. Sprotzer

Keyword(s):

Sex Differences ◽

Eighth Graders ◽

Developmental Changes ◽

Third Grade ◽

Fifth Grade ◽

Eighth Grade ◽

Self Perceptions ◽

Self Confidence ◽

Sex Stereotypes

Sex differences in self-perceptions of intelligence and self-confidence were examined among third through eighth graders. In third grade, differences between the sexes were small and, in the case of perceptions of intelligence, favored the females. By fifth grade, males were more likely to describe themselves as smart and self-confident than were females. These differences persisted into the eighth grade. Further analyses indicated that the sex differences could not be adequately explained by the process of internalizing sex-stereotypes.

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Role of steroid hormones in Trichinella spiralis infection among voles

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1999.277.5.r1362 ◽

1999 ◽

Vol 277 (5) ◽

pp. R1362-R1367 ◽

Cited By ~ 8

Author(s):

Sabra L. Klein ◽

H. Ray Gamble ◽

Randy J. Nelson

Keyword(s):

Sex Differences ◽

Immune Function ◽

Steroid Hormones ◽

Trichinella Spiralis ◽

Parasite Burden ◽

Parasite Infection ◽

Prairie Voles ◽

Meadow Voles ◽

Functional Explanations

Males are generally more susceptible to parasite infection than females. This sex difference may reflect the suppressive effects of testosterone and enhancing effects of estradiol on immune function. This study characterized the role of circulating steroid hormones in sex differences after infection with the nematode Trichinella spiralis. Because testosterone suppresses immune function and because polygynous males have higher circulating testosterone concentrations than monogamous males, sex differences in parasite burden were hypothesized to be exaggerated among polygynous meadow voles compared with monogamous prairie voles. As predicted, sex differences in response to T. spiralis infection were increased among meadow voles; males had higher worm numbers than females. Male and female prairie voles had equivalent parasite burden. Overall, prairie voles had higher worm numbers than meadow voles. Contrary to our initial prediction, differences in circulating estradiol concentrations in females, testosterone concentrations in males, and corticosterone concentrations in both sexes were not related to the observed variation in T. spiralisinfection. Taken together, these data suggest that not all sex differences in parasite infection are mediated by circulating steroid hormones and that adaptive-functional explanations may provide new insight into the causes of variation in parasite infection.

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