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J Fray

Publications and source records attributed to J Fray.

4 recordsLinked to original sources
PubMed2001

Spontaneous pregnancy-induced hypertension and intrauterine growth restriction in rats.

The SHHF/Mcc-fa(cp) (spontaneous hypertension and heart failure) rat is advanced as a novel and suitable non-primate model of pregnancy-associated hypertension and fetal growth restriction because it simultaneously has spontaneous pregnancy-associated hypertension, small for gestational age (SGA) offsprings, and altered placental gene expression. Pregnancy-associated hypertension is a major contributor to maternal and fetal morbidity and mortality with the potential to result in maternal death and the need for iatrogenic preterm delivery. It has been reported to develop spontaneously in humans, but not in animals; consequently, progress in identifying the cause and pathogenesis of this disorder has been hampered. Spontaneous hypertension and heart failure rats develop hypertension spontaneously as they age, therefore we sought to determine whether these rats developed hypertension and SGA offsprings during pregnancy. Our results show that systolic blood pressure (BP) increased >40 mm Hg by the end of the first trimester and remained at this elevated level for the remainder of pregnancy, but decreased after parturition. Placenta weights of SHHF rats (0.60 +/- 0.02 g, n = 36) were significantly higher than Wistar-Kyoto (WKY) rats (0.42 +/- 0.01 g, n = 22, P < .05), but pup weights were significantly lower (2.68 +/- 0.06 g for SHHF rats compared to 3.24 +/- 0.06 g for WKY controls, P < .05). Histologic examination revealed pathologic lesions in neither heart, liver, placenta, nor kidney. L-Arginine administered in drinking water prevented the elevation of BP, particularly during the third trimester. Placentas from SHHF rats displayed altered expression of several genes whose protein products have been implicated in preeclampsia, including serotonin receptor, sodium channel, carbonic anhydrase, estrogen receptor regulator, major histocompatibility complex proteins, superoxide dismutase, and angiotensiogen. In addition, gene expression profiling showed alteration of a number of subcellular putative myristoylproteins not previously associated with preeclampsia, particularly those engaged in post-translational modifications in the placenta. Thus, SHHF rats may be a valuable tool, because it simultaneously has spontaneous pregnancy-associated hypertension, SGA offsprings, and altered placental gene expression.

Angiotensinogen↗
PubMed2000

Hypertension and insulin resistant models have divergent propensities to learned helpless behavior in rodents.

The induction of learned helpless (LH) behavior in rats is a widely used model of unipolar depression. Recent studies have linked depression with hypertension and insulin resistance as observed in obesity, but the propensity of these disorders to manifest depression has not been reported. In this study, the LH behavioral paradigm was exploited in a model of hypertension (Dahl rat) and of insulin resistance (Zucker rat) to determine the propensity of these models to develop depression and to examine the profile of markers for the propensity of the cardiovascular system (plasma renin activity) and of the hypothalamus-pituitary-adrenal axis (corticosterone) in the display of propensity to depression. Results show that Zucker rats displayed the lowest propensity to the development of LH behavior (12%), followed by the control Sprague-Dawley rats (27%), and then Dahl rats (66%). In contrast, congenital learned helpless (cLH) rats, a genetically bred strain for animal depression, had the highest propensity (>90%). A gender effect was observed in the Zucker and cLH rats, with females showing an increased propensity to develop LH behavior. Plasma renin activity in the Dahl and Sprague-Dawley rats after the LH stress paradigm was not significantly different from baseline. In contrast, Zucker rats, with the lowest propensity to LH behavior, demonstrated a threefold increase in plasma renin activity after stress. Congenital LH rats, with the highest propensity to LH behavior, exhibited a significantly lower increase (43%) in plasma renin activity after stress. Hyporesponsive hypothalamus-pituitary-adrenal (HPA) axis functioning correlated with propensity of LH behavior. Stress-induced corticosterone levels increased under twofold in cLH rats, whereas they increased more than sevenfold in Zucker rats. Taken together, these studies suggest that whereas genetically prone hypertensive rats have a very high propensity to depression, insulin-resistant rats have a profound resistance to depression. Moreover, a hyporesponsive HPA axis may be a marker for disorders that are comorbid with depression, whereas a hyperresponsive renin-angiotensin system may be indicative of resilience.

Animals↗
PubMed1994

A mental health capitation program: I. Patient outcomes.

OBJECTIVE: The Monroe-Livingston demonstration project's capitation payment system (CPS) was evaluated to determine whether capitated funding of mental health care, compared with fee-for-service funding, could reduce hospitalization rates and improve functioning and symptoms for severely and persistently mentally ill adults without increasing the total cost of care. METHODS: The experiment was a communitywide prerandomized clinical trial involving 422 patients. Patients who were randomized into the experimental group were eligible for enrollment in a capitated funding program administered by one of five community mental health centers. Those randomized into the control group received standard fee-based services. Follow-up interviews with patients one and two years after enrollment in the study assessed changes in symptoms and functioning. Data files of the membership corporation that coordinated community mental health services for the CPS provided measures of study patients' use of inpatient mental health services. RESULTS: During the two-year follow-up period, patients in the experimental group had significantly fewer hospital inpatient days than patients in the control group, but the two groups had no significant differences in functioning or level of symptoms. CONCLUSIONS: The CPS successfully maintained severely ill patients in the community but did not improve their functioning or level of symptoms.

Adult↗