Food access modifies GnIH, but not CRH, cell number in the hypothalamus in a female songbird

Food deprivation or restriction causes animals to mount a stereotypical behavioral and physiological response that involves overall increases in activity, elevated glucocorticoid production, and (often) inhibition of the reproductive system. Although there is increasing evidence that these responses can differ in their degree or covariation between the sexes, most studies to-date on food restriction/deprivation have focused on male songbirds. We therefore aimed to characterize the behavioral, physiological, and neuroendocrine response to acute food deprivation in a female songbird using a nomadic species, the zebra finch. We quantified behavior during a 6.5 h food deprivation and then measured physiological and neuroendocrine responses of female birds at the 6.5 h timepoint. Within 1 h of acute food deprivation, female zebra finches increased foraging behaviors, and after 6.5 h of food deprivation, females lost 5% of their body mass, on average. Change in body mass was positively associated with elevated corticosterone and (contrary to findings in male zebra finches) negatively related to the number of gonadotropin inhibitory hormone-immunoreactive cells in the hypothalamus. However, there was no effect of food deprivation on corticotropin releasing hormone-immunoreactive cells in the hypothalamus. There was also no relationship between corticotropin releasing hormone-immunoreactive cell number and circulating corticosterone. Our results are consistent with the hypothesis that neuroendocrine responses to food deprivation differ between male and female songbirds. Future studies should work to incorporate sex comparisons to evaluate sex-specific neuroendocrine responses to acute stress.

Volunteer advocates: differing role expectations of long-term care facility administrators and volunteers

Volunteers and volunteer advocates are becoming important members of the long-term care team. A much needed improvement in volunteer advocacy programs is the development of mutual consensus between volunteers and facility administrators.

Axons containing the growth associated protein GAP-43 specifically target rat corticotrophs following adrenalectomy

An extensive network of nerve fibers immunoreactive for the neuronal growth associated protein GAP-43 (GAP-43-IR) is present within the anterior pituitary (AP) of the rat, and the density of these fibers has been reported to increase 4 days after adrenalectomy (ADX). In the present study, we employed confocal dual-label immunofluorescence microscopy to determine whether GAP-43-IR fibers are specifically associated with corticotrophs at various intervals after ADX. A dramatic increase in the density of GAP-43-IR was apparent 4 days after ADX, and this increase was sustained at 7 and 14 days post-ADX. The percentage of corticotrophs in apparent contact with GAP-43-IR axons was 87% at 4 days after ADX and 92% at 14 days. In addition, fewer than 15% of GAP-43-IR terminals were associated with cells other than corticotrophs in either group. This highly specific targeting of corticotrophs during a period in which these cells are undergoing both hypertrophy and hyperplasia indicates that axonal sprouting is occurring in response to ADX. While the less intense GAP-43-IR in the AP of intact rats precluded precise quantitative analysis, the majority of corticotrophs also appeared to be selectively innervated in these animals. The observations that GAP-43-IR axons selectively contact corticotrophs, and that both the specificity and thoroughness of innervation are maintained by targeted growth of GAP-43-IR axons following ADX, strongly suggest that these fibers are of functional significance.

Social interaction and life satisfaction: an empirical assessment of late-life patterns

Problems of social and psychological adjustment in later life have been examined by numerous investigators. Some have found positive relationships between social interaction and personal adjustment, while others have found interaction and adjustment to be unrelated. The purpose of the research reported here was to examine how different ways of measuring interaction may affect its relationship with personal adjustment. Data were obtained in interviews with 218 noninstitutionalized persons aged 70 and older. Findings indicate that both the number of persons interacted with, and the frequency of this interaction, are of little importance for the adjustment of older people. We suggest that the quality, rather than quantity, of social interaction is crucial to understanding adaptations to old age.

Structural effects and life satisfaction among the aged

This study investigates whether adjustment, or life satisfaction, is a function of the structural effect of community age density, the behavioral varaibles of total social interaction and age-graded interaction, or both. The sample contains one hundred eight-five persons seventy years of age and older in a midwestern state who have resided in their community at least five years. Thus, the study examines the influence of community structure on life satisfaction, age-graded interaction, and total interaction in a "real world" setting by using a relatively non-mobile sample. The findings suggest that no significant relationship exists between community structure and either total or age-graded interaction. Age-graded interaction, however, is significantly correlated with life satisfaction in large communities.