Adrenal cortical response to circumcision in the neonate

A study was designed to document the responsiveness of the hypothalamic-pituitary-adrenal axis to the stress of circumcision during the first 6 hours of life. There was a rise in both serum cortisol and cortisone levels in all infants studied. The rise in cortisol was greater than the rise in cortisone in all infants.     

Increased epinephrine-induced cAMP response in severely diabetic BB/W rat liver

The effect of prolonged diabetes on epinephrine-induced adenosine 3',5'-monophosphate (cAMP) response in the liver was examined in diabetes-prone BB/W rats. Basal and 1 microM epinephrine-induced cAMP release from isolated perfused liver was similar in non-diabetic and diabetic BB/W rats with preserved adipose tissue. In adipose tissue-absent diabetic rats losing intra- and retro-peritoneal adipose tissue completely, both basal and 1 microM epinephrine-induced cAMP release from the liver were enhanced (P<0.01, each case). Plasma epinephrine and norepinephrine were similar in non-diabetic, adipose tissue-preserved and -absent diabetic BB/W rats. The plasma free thyroxine level was similar in non-diabetic and adipose tissue-preserved diabetic BB/W rats, but was lower in adipose tissue-absent diabetic BB/W rats than in non-diabetic rats (P<0.01), but the frequency of lymphocytic thyroiditis was similar in these three groups, although plasma corticosterone was lower in adipose tissue-preserved diabetic BB/W rats (P<0.05) and the lowest in adipose tissue-absent diabetic BB/W rats (P<0.01). Lymphocytic infiltration was not observed in the adrenal or pituitary glands in any group. Plasma total protein and albumin were low in adipose tissue-absent diabetic BB/W rats (P<0.01, each case). In adipose tissue-absent diabetic BB/W rats, liver dysfunction and hepatomegaly, but no apparent histological change in the liver, were observed. Plasma glucose was higher (P<0.01) and plasma insulin lower (P<0.05) in adipose tissue-absent diabetic BB/W rats than in adipose tissue-preserved diabetic BB/W rats. In conclusion, epinephrine-induced cAMP response in the liver was enhanced only in adipose tissue-absent diabetic BB/W rats. Denervation supersensitivity was not likely to be responsible for the enhanced beta-adrenergic response. The observed reductions in plasma thyroxine and corticosterone seemed to result from severe diabetes. Although the severity of diabetes can vary continuously, severe diabetes with loss of adipose tissue appeared to cause significant changes in the metabolism and enhanced beta-adrenergic response in the liver.     

Adrenal function in the diabetic mutant mouse (gene symbol dbm)

The adrenal function in diabetes mutant mice with misty coat colour (dbm) was investigated by measurements of serum corticosteroids, adrenal weights and adrenal corticosteroid content. Furthermore, the adrenal corticosteroid content was studied in obese-hyperglycemic mice (ob). In the dbm-mice the serum corticosteroid levels were elevated at the age of 5 and 12 months although the adrenal weight only was significantly elevated at the age of 5 months. The adrenal corticosteroid content was significantly lower in the 12 months old dbm-mice. In the ob-mice the adrenal corticosteroid content was elevated at the age of 5 weeks, 5 and 12 months. It is concluded that in both the dbm-mouse and the ob-mouse there is an increased functional activity of the adrenal cortex which may reflect a pituitary hypersection of ACTH, perhaps as a manifestation of a common hypothalamic disorder.     

Rats and mice together: The predatory nature of the rat's mouse-killing response.

Distinguishes between predatory behavior and other types of behavior typically called aggressive (e.g., territorial fighting). Predatory behaviors are (a) usually interspecific, (b) related to eating, and (c) topographically distinct from other fighting behaviors. It is suggested that differences in response patterns offer a relatively simple way to distinguish predatory behaviors from other fighting behaviors. Studies of the rat's mouse-killing response are reviewed and compared with those of predatory animals according to the criteria listed above. It is concluded that the rat's mouse-killing response is predatory (i.e., a link in a behavioral chain that typically ends in eating). This definition is important for the consideration of future conditioning studies concerned with the modification of such behavior. (52 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adrenal cortex response to adrenocorticotropic hormone in dairy cattle

Adult dairy cows were treated with a range of doses (0.0125mg to 0.4mg) of synthetic ACTH1-24 and the plasma cortisol response was measured. Peak response was independent of dose. Higher doses of ACTH had a more prolonged effect such that the integrated response was dose dependent. Dose response curves were examined by regression analyses. Individual cows had a significant effect on y-axis intercept but not on the slope of the regression lines examined. A dose rate of 0.05mg ACTH iv was identified as a suitable dose rate for use in clinical assessment of adrenal cortex function, with 0, 50 and 120 min following ACTH being critical sampling times to identify the response.     

Heterologous antibodies in human and rat's glioblastoma

IgG from immunized rabbits was labelled with Fluorescein Isothiocyanate, and conjugated in vitro with human and with rat glioblastoma. After absorption of the antisera with normal brain and liver, a heavy concentration of antibody was found in the rat tumour cells. A great amount of antibody was also found in the human neoplastic cells. The incorporation of this antibody in glioma cells of different rats developing new tumours indicates that transplantation antigens of the H-2 type are not the only ones capable of inducing specific antibody attachment.     

In vivo response of the rat's retinal pigment epithelium to azide: changes induced by light damage

Functional changes in retinal pigment epithelium (RPE) associated with light-induced retinal damage were studied by measuring transocular potential changes evoked by injections of azide and thiocyanate (SCN-). The retinal damage by light in the rat is classified into two types: Type 1, rod cell death associated with RPE deterioration; Type 2, the loss of rod cells without RPE deterioration. To study the type 1 damage, littermate pairs of long-term dark-adapted adult albino rats were tested at 1 h and 10 d after the exposure to green light of 1,200 lx for 1/2 to 24 h. Time course of the damage progress was also followed for 12 h. We found that 1) RPE was affected rapidly by the damaging light, 2) the exposure length determined the ultimate degree of RPE damage, 3) damaging effects on RPE proceeded slower and weaker after exposure than during continuous light, 4) progress of the damage in RPE was two-phasic; during the first phase, the SCN- response was enhanced and the azide response was reduced; both responses were decreased rapidly in the second phase. The first phase was assumed to indicate a depolarization of the basolateral membrane of RPE, and the second phase to manifest the structural deterioration of RPE. The type 2 damage was studied in young rats with exposure to weak light for 28 d. At 30 d after the exposure, a-wave of the ERG and number of rod cells were substantially reduced but azide and SCN- responses were affected slightly.     

Adrenal androgenic response to 2-hour ACTH stimulation test in women with PCOS

Breast carcinoma metastases to the eye occur more frequently than is clinically recognized. The prevalence of this lesion is not appreciated because of the dominant clinical picture of metastases occurring in other organs or because a number of eye lesions are small and asymptomatic. With the increasing length of survival, more breast cancer patients will require care for ocular metastases. A thorough ophthalmic evaluation, aided by computed tomography or magnetic resonance imaging, usually confirms the diagnosis. Rapid progression of a lesion demands emergency therapy since the dysfunction produced by progressive disease may not otherwise be corrected. Early diagnosis of ocular metastases in patients with breast cancer is important because timely treatment may improve vision and quality of life in the time remaining to patients. Experience with two cases of metastases to the eye from breast cancer are presented, with a review of the literature.     

Impaired vitamin D metabolism and response in spontaneously diabetic GK rats

Several studies of diabetes mellitus patients have demonstrated abnormalities in calcium, phosphate and vitamin D metabolism. In an earlier study, the authors reported impaired renal processing of phosphate in spontaneously diabetic GK rats, an animal model of type II diabetes mellitus. In the present study, which represents an extension of the earlier study, vitamin D metabolism and response are examined in 20-week-old GK rats. Serum 1,25-dihydroxyvitamin D [1,25-(OH)2D] was found to be lower in GK rats than in Wistar rats. After intraperitoneal administration of 0.5 micrograms/kg 1,25-(OH)2D, serum calcium increased in GK rats, but not in Wistar rats, while serum phosphate remained unchanged in GK rats, but increased in Wistar rats. Although serum 1,25-(OH)2D rose abruptly in 3 h and decreased thereafter in both GK and Wistar rats, the decrease in serum 1,25-(OH)2D at 6 h was more marked in GK rats than in Wistar rats. Serum 24,25-dihydroxyvitamin D was consistently higher in GK rats than in Wistar rats. Northern blotting and dot blotting with use of a cDNA probe for the 24-hydroxylase gene showed an increased expression of the gene in the kidney of GK rats. These results demonstrate impaired vitamin D metabolism in GK rats. Increased activity of 24-hydroxylase, in addition to impaired phosphate metabolism, may play a role in impaired vitamin D metabolism in GK rats.     

Stress and ulceration in the glandular and nonglandular portions of the rat's stomach.

Previous studies indicate that conditioned fear and conflict produce ulceration in the nonglandular portion of the rat's stomach (rumen), while immobilization produces ulceration in the glandular portion (corpus). The present 3 experiments were conducted with Maudsley Reactive, Maudsley Nonreactive, and male Sprague-Dawley rats (N = 66). Exp I and II tested the course of ulceration in the corpus and rumen under stress conditions. Ulceration was induced in the corpus by partial restraint. Ulcerated Ss were then exposed to conditioned fear for 72 hrs (Exp I) and 48 hrs (Exp II) and were compared with controls. Exp I showed that glandular lesions healed while nonglandular lesions developed in food-deprived Ss. Nonglandular ulcers did not appear during the 48 hrs of Exp II. Exp III showed a positive relationship between rumenal ulceration and food deprivation. Rumenal ulceration induced by conflict and conditioned fear procedures mainly seems to reflect the suppression of food intake by these procedures. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lipolytic response during spontaneous hypoglycaemia in insulin-dependent diabetic subjects

OBJECTIVE: To gather qualitative data regarding HIV/AIDS patients' perspectives about HIV-1 protease inhibitors (PIs), and about their experiences taking and adhering to regimens containing PIs. DESIGN: Six focus groups of persons under care for HIV were conducted between September and November 1996 regarding participants' knowledge, awareness, experiences when taking, and adherence to antiretroviral regimens containing PIs. An identical discussion guide was used to facilitate all six groups. Focus group proceedings were audiotaped, transcribed, coded for themes, and analyzed qualitatively. SETTING: HIV/AIDS practices of three teaching hospitals and two community health centers. PATIENTS/PARTICIPANTS: Fifty-six patients with HIV disease: 28 men and 28 women. MEASUREMENTS AND MAIN RESULTS: Knowledge and positive impressions of PIs were prevalent among this diverse group of persons with HIV, and did not differ by race/ethnicity or gender. Most knew that these were new, potent medications for treating HIV/AIDS. Networks of persons with HIV and medical providers were the most important information sources. Those taking PIs were aware that adherence to the regimen is important, and most were using special strategies to maximize their own adherence, but expressed considerable frustration about the central role these medication regimens had assumed in their life. A subset who did not believe they would adhere to these regimens had declined treatment with them. Motivating factors for taking and adhering to these complex regimens were improving CD4 counts and viral loads and the patient-provider relationship. CONCLUSIONS: Among those with HIV/AIDS, awareness of PIs and their effectiveness is substantial, owing to the impact of informal networks and medical providers. This early positive "reputation" of PIs may enhance motivation for adherence. Those who are taking PIs invest substantial effort adhering to these complex regimens, but resent the need to make medications the focus of their lives.     

Decrease of vascular response to iloprost in diabetic rats

The current advances in molecular genetics and gene transfer are introduced together with the existing international research programs on these technologies. The opportunities for exploitation are discussed and how they could be incorporated into current breeding programs. Finally, issues of public concern and acceptability are raised and put into the context of existing breeding schemes and regulations.     

Mental and physical stress as moderators of the postural response in insulin-dependent diabetic patients.

In 14 insulin-dependent diabetic patients (mean age 31.3 yrs) and in 15 normal controls (mean age 30.9 yrs), continuous measures were taken of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and skin conductance (SC) during postural change under baseline and stressor conditions. Diabetic Ss without symptoms of neuropathy and healthy controls showed generally similar responses to postural change and to stressor conditions (mental arithmetic and isometric handgrip). SBP and DBP were more responsive to mental and physical stressors than were HR or SC, especially after standing. Two diabetics with postural hypotension showed significant increases in overall BP levels and less of a fall in BP during postural change under the stressor conditions, despite minimal HR or SC responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changes in electrophysiological properties and noradrenaline response in vas deferens of diabetic rats

The purpose of this study was to study changes in the sympathetic nerves of the vas deferens in 10-week-old streptozotocin-induced diabetic rats. To assess the activity of autonomic neurons, we recorded the amplitude and frequency of spontaneous junction potentials in vasa deferentia from age-matched controls and streptozotocin-induced diabetic rats. No change in the resting membrane potential of the smooth muscle of the vas deferens was found in streptozotocin-induced diabetic rats. The frequency of spontaneous junction potentials was significantly increased in the streptozotocin-induced diabetic rats and their amplitude was also markedly increased. The dose-response curve for the contractile response of the vas deferens to noradrenaline was significantly shifted to the right and the apparent affinity (pD2 value) was significantly decreased in streptozotocin-induced diabetic rats. These results suggest that degeneration of sympathetic neurons may occur in the vas deferens of 10-week streptozotocin-induced diabetic rats and that the greater amplitude of the spontaneous junction potentials may be related to an increase in Ca2+ mobilization, though the increase in Ca2+ mobilization does not lead to an enhanced contractile response.     

Osmosensitive neurons in the rat's preoptic area: Medial-lateral comparison.

Conducted an experiment with 17 Charles River Long-Evans hooded rats in which, for the 1st time, brain-recording data were brought to bear directly on the question of a critical osmosensitive zone in the lateral preoptic area as specifically delimited in the rat by E. M. Blass and A. N. Epstein (see record 1972-02252-001) and in the rabbit by J. W. Peck and D. Novin (see record 1971-07490-001). The present data clearly show that this critical zone in the lateral preoptic area of the rat contains cells that are osmosensitive. Simultaneous recording from cell populations (a) inside the critical zone and (b) in a zone medial to it showed that the net acceleratory response to challenge for the former was much greater than it was for the latter. Findings constitute new evidence for the critical importance of the lateral preoptic area in cellular dehydration thirst. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does the presence of diabetic nephropathy in parents influence the metabolic response in the offspring?

Non-insulin dependent (Type 2) diabetes mellitus (NIDDM) and long-term complications such as nephropathy have a strong genetic predisposition. Insulin resistance is thought to be a pathogenetic factor, predisposing genetically prone individuals to develop the microvascular complications of diabetes. To test these hypotheses, two groups of young individuals were studied: 28 offspring of parents having NIDDM and diabetic nephropathy (group 1) aged 29.5 +/- 6.1 years, BMI 25.2 +/- 4.7 kg m(-2) and 31 offspring of diabetic parents with no history of nephropathy, aged 31.6 +/- 4.1 years and BMI 26.3 +/- 4.9 kg m(-2) (group 2). All underwent a standard oral glucose tolerance test with measurement of serum insulin levels and serum lipid profile. Urine albumin:creatinine ratio (A/C ratio) and blood pressure were also recorded. Diabetes was detected in 2/28 (7.1%) and 3/31 (9.7%) and IGT was detected in 5/28 (25%) and 8/31 (25%) of groups 1 and 2, respectively. These differences were not statistically significant, but were higher than in a group of non-diabetic controls with healthy parents. Comparison of the normoglycaemic subjects (19 and 20 in group 1 and 2, respectively) showed no significant differences between blood pressure readings, fasting and 2 h plasma glucose, and lipid profiles. Plasma insulin values, fasting and 2 h, and the area under the graph were also similar in both groups, indicating an absence of higher insulin response in group 1 in comparison with group 2. These values were also not different from those in the non-diabetic controls. A delay in insulin response to glucose was noted in many of the offspring as indicated by a low deltaI/deltaG at 30'. We conclude that offspring of diabetic parents with nephropathy do not show higher risk of glucose intolerance or insulin resistance compared to those with diabetic parents without nephropathy. The relatively high plasma glucose values in the presence of normal insulin secretion in both groups of offspring of diabetic parents suggest the presence of insulin resistance.     

How attendance and quality of participation affect treatment response to parent management training.

This study examined whether attendance and quality of participation in parent management training predicted treatment response. Data were from 445 parents (55% minority, 62% single; almost all of low socioeconomic status) who had 1st-grade children with severe conduct problems. Quality of participation in weekly parent groups was based on group leader ratings. Parent outcomes were based on interviewer ratings, behavioral observations, parent reports, and teacher ratings. Results of hierarchical linear models suggested that few family characteristics predicted attendance in this efficacy trial and that attendance was not related to changes in parenting over the year. However, several family characteristics predicted quality of participation in parent management training, and this in turn predicted changes in parental perceptions, warmth, physical punishment, and school involvement. From a clinical perspective, these findings suggest that it is not enough to get parents to attend sessions; it is also necessary to facilitate their active engagement in the therapeutic process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Primacy of liver glucosensors in the sympathetic response to progressive hypoglycemia

The impact of hepatic glucose concentration on the sympathetic response to progressive hypoglycemia was examined in chronically cannulated conscious male dogs (n = 6). Graded hypoglycemia was induced via peripheral insulin infusion (30 pmol.kg-1.min-1) with either peripheral (PER) or portal (POR) glucose infusion. Over the 260-min experimental period, arterial glycemia was adjusted from 5.2 +/- 0.1 to 2.5 +/- 0.1 mM in decrements of approximately 0.5 mM every 40 min. Arterial glycemias were not significantly different between PER and POR at any measured level. However, hepatic glycemia was significantly elevated at all times during POR (8.4 +/- 0.8 to 3.4 +/- 0.2 mM) when compared to PER (5.2 +/- 0.2 to 2.5 +/- 0.1 mM). Plasma epinephrine values were significantly greater during PER vs. POR at all arterial glycemias below 4.0 mM. At the lowest level of arterial glycemia studied (2.5 +/- 0.2 mM) the epinephrine response above basal was 3-fold greater for PER (8.7 +/- 1.7 nM) when compared to POR (2.6 +/- 0.6 nM) (P < 0.01). Plasma norepinephrine results were similar for the two protocols, with PER demonstrating a 3-fold greater response above basal when compared to POR at 2.5 mM arterial glycemia (P < 0.05). While the sympathetic response was markedly different between protocols when expressed as a function of arterial glycemia, when expressed as a function of hepatic glycemia this discrepancy was largely eliminated. This latter observation supports the liver as the primary locus for glycemic detection relevant to the sympathoadrenal response when hypoglycemia develops slowly--i.e., over a period of 2-3 h. A comparison of the current findings with our previous observations suggests that the hepatic glucosensors may play a greater role in hypoglycemic counterregulation as the rate of fall in glycemia is less.