Distinct dynamics of social motivation drive differential social behavior in laboratory rat and mouse strains

Mice and rats are widely used to explore mechanisms of mammalian social behavior in health and disease, raising the question whether they actually differ in their social behavior. Here we address this question by directly comparing social investigation behavior between two mouse and rat strains used most frequently for behavioral studies and as models of neuropathological conditions: C57BL/6 J mice and Sprague Dawley (SD) rats. Employing novel experimental systems for behavioral analysis of both subjects and stimuli during the social preference test, we reveal marked differences in behavioral dynamics between the strains, suggesting stronger and faster induction of social motivation in SD rats. These different behavioral patterns, which correlate with distinctive c-Fos expression in social motivation-related brain areas, are modified by competition with non-social rewarding stimuli, in a strain-specific manner. Thus, these two strains differ in their social behavior, which should be taken into consideration when selecting an appropriate model organism

Feasibility and preliminary efficacy of acupuncture for angina in an underserved diverse population

PurposeStable angina is ischemic chest pain on exertion or with emotional stress. Despite guideline-directed therapy, up to 30% of patients have suboptimal pain relief. The aims of this study were to: (1) determine the feasibility and acceptability of a randomized controlled trial (RCT) of acupuncture; and (2) evaluate preliminary efficacy of acupuncture with respect to reduction of pain and increased functional status and health-related quality of life (HRQoL).MethodsParticipants with stable angina for ⩾1 month received either a standardized acupuncture protocol, twice per week for 5 weeks, or an attention control protocol. Measures included the McGill Pain Questionnaire (average pain intensity (API), pain now) and the Seattle Angina Questionnaire-7 (functional status, symptoms, and HRQoL). Feasibility was defined as ⩾80% recruitment, ⩾75% retention following enrollment, and ⩾80% completion. Descriptive statistics and mixed-effects linear regression were used for analysis.ResultsThe sample (n = 24) had a mean age of 59 ± 12 years, was predominantly female (63%), and represented minority groups (8% White, 52% Black, 33% Hispanic, and 8% Other). Feasibility was supported by 79% retention and 89% completion rates. The recruitment rate (68%) was slightly lower than expected. Acceptability scores were 87.9% for the acupuncture group and 51.7% for the control group. Outcomes were significantly better for the acupuncture versus control groups (API, b = -2.1 (1.1), p = 0.047; functional status, b = 27.6 (7.2), p < 0.001; and HRQoL, b = 38.8 (11.9), p = 0.001).Conclusions and implicationsAcupuncture was feasible and acceptable in our diverse sample. We were slightly under the recruitment target of 80%, but participants who started the study had a high likelihood of completing it. Acupuncture shows promise for stable angina, but its effectiveness needs to be confirmed by a larger, adequately powered RCT.Trial registration numberNCT02914834 (ClinicalTrials.gov)

Breastfeeding, Cellular Immune Activation, and Myocardial Recovery in Peripartum Cardiomyopathy

• The impact of breastfeeding on prolactin, cellular immune activation, and myocardial recovery was analyzed in 100 women with peripartum cardiomyopathy • Cardiac function was assessed by echocardiography at presentation and at serial intervals over the first year postpartum • The levels of circulating prolactin were assessed by ELISA, and cellular immunophenotyping by flow cytometry, and compared between breastfeeding and nonbreastfeeding women • Prolactin levels were higher in breastfeeding women and correlated with significant increases in CD8+ T cells • Despite significantly higher prolactin levels and increased CD8+ cells, myocardial recovery was similar in breastfeeding and nonbreastfeeding women The etiology of peripartum cardiomyopathy remains unknown. One hypothesis is that an increase in the 16-kDa form of prolactin is pathogenic and suggests that breastfeeding may worsen peripartum cardiomyopathy by increasing prolactin, while bromocriptine, which blocks prolactin release, may be therapeutic. An autoimmune etiology has also been proposed. The authors investigated the impact of breastfeeding on cellular immunity and myocardial recovery for women with peripartum cardiomyopathy in the IPAC (Investigations in Pregnancy Associated Cardiomyopathy) study. Women who breastfed had elevated prolactin, and prolactin levels correlated with elevations in CD8 + T cells. However, despite elevated prolactin and cytotoxic T cell subsets, myocardial recovery was not impaired in breastfeeding women

Myocardial Damage Detected by Late Gadolinium Enhancement Cardiac Magnetic Resonance Is Uncommon in Peripartum Cardiomyopathy

In peripartum cardiomyopathy, the prevalence of focal myocardial damage detected by late gadolinium enhancement (LGE) cardiovascular magnetic resonance is important to elucidate mechanisms of myocardial injury and cardiac dysfunction. LGE equates irreversible myocardial injury, but LGE prevalence in peripartum cardiomyopathy is uncertain. Among 100 women enrolled within the Investigations of Pregnancy Associated Cardiomyopathy cohort, we recruited 40 women at 13 centers to undergo LGE cardiovascular magnetic resonance, enrolled within the first 13 weeks postpartum. Follow-up scans occurred at 6 months postpartum, and death/transplant rates at 12 months. Baseline characteristics did not differ significantly in the parent cohort according to cardiovascular magnetic resonance enrollment except for mechanical circulatory support. LGE was noted only in 2 women (5%) at baseline. While left ventricular dysfunction with enlargement was prevalent at baseline cardiovascular magnetic resonance scans (eg, ejection fraction 38% [Q1-Q3 31-50%], end diastolic volume index=108 mL/m [Q1-Q3 83-134 mL/m ]), most women demonstrated significant improvements at 6 months, consistent with a low prevalence of LGE. LGE was not related to baseline clinical variables, ejection fraction, New York Heart Association heart failure class, or mortality. Neither of the 2 women who died exhibited LGE. LGE was inversely associated with persistent left ventricular ejection fraction at 6 months ( =0.006). Factors other than focal myocardial damage detectable by LGE explain the initial transient depressions in baseline left ventricular ejection fraction, yet focal myocardial damage may contribute to persistent myocardial dysfunction and hinder recovery in a small minority. Most women exhibit favorable changes in ventricular function over 6 months. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01085955

Myocardial Damage Detected by Late Gadolinium Enhancement Cardiac Magnetic Resonance Is Uncommon in Peripartum Cardiomyopathy

In peripartum cardiomyopathy, the prevalence of focal myocardial damage detected by late gadolinium enhancement (LGE) cardiovascular magnetic resonance is important to elucidate mechanisms of myocardial injury and cardiac dysfunction. LGE equates irreversible myocardial injury, but LGE prevalence in peripartum cardiomyopathy is uncertain. Among 100 women enrolled within the Investigations of Pregnancy Associated Cardiomyopathy cohort, we recruited 40 women at 13 centers to undergo LGE cardiovascular magnetic resonance, enrolled within the first 13 weeks postpartum. Follow-up scans occurred at 6 months postpartum, and death/transplant rates at 12 months. Baseline characteristics did not differ significantly in the parent cohort according to cardiovascular magnetic resonance enrollment except for mechanical circulatory support. LGE was noted only in 2 women (5%) at baseline. While left ventricular dysfunction with enlargement was prevalent at baseline cardiovascular magnetic resonance scans (eg, ejection fraction 38% [Q1-Q3 31-50%], end diastolic volume index=108 mL/m [Q1-Q3 83-134 mL/m ]), most women demonstrated significant improvements at 6 months, consistent with a low prevalence of LGE. LGE was not related to baseline clinical variables, ejection fraction, New York Heart Association heart failure class, or mortality. Neither of the 2 women who died exhibited LGE. LGE was inversely associated with persistent left ventricular ejection fraction at 6 months ( =0.006). Factors other than focal myocardial damage detectable by LGE explain the initial transient depressions in baseline left ventricular ejection fraction, yet focal myocardial damage may contribute to persistent myocardial dysfunction and hinder recovery in a small minority. Most women exhibit favorable changes in ventricular function over 6 months. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01085955