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R S Surwit

Publications and source records attributed to R S Surwit.

86 records · Page 5Linked to original sources
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Type A behavior pattern and blood glucose control in diabetic children.

We studied the relationship between presence of Type A behavior pattern and glycemic response to stress in children with insulin dependent diabetes mellitus (IDDM). Twelve male (six Type A and six Type B) and nine female (four Type A and five Type B) insulin-dependent diabetic patients between the ages of 8 and 16 years received a standard meal and blood glucose values were assessed two hours later. All subjects then played a competitive videogame for 10 minutes following which blood glucose was assessed again. Preprandial and postprandial blood glucose values did not differ between the groups. However, only Type A subjects showed a hyperglycemic response to the videogame stress. Type A subjects also demonstrated significantly higher glycohemoglobin values. In order to assure that this effect was due to a differential response to stress and not simply a difference in metabolic response to a meal, a second study was conducted in which blood glucose values were assessed at one, two and three hours following a standard meal. No significant differences in postprandial blood glucose values were observed between Type A and Type B subjects. These data support previous research which has suggested that some but not all patients with IDDM show a hyperglycemic response to stress.

Adolescent↗
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Opioid dysfunction and risk for hypertension: naloxone and blood pressure responses during different types of stress.

Opioidergic inhibition of sympathetic nervous system responses may be deficient in persons at risk for essential hypertension (McCubbin et al: Hypertension 7:808, 1985). The opiate antagonist naloxone increases blood pressure responses during psychological stress in young adults with low causal blood pressure, but has no pressor effect in subjects with high casual blood pressure. The purpose of the present study was to determine the role of altered baroreflex function in the abnormal pressor effect of naloxone in persons at risk for hypertension development. We tested this by comparison of the effects of naloxone on responses to psychological stress with responses to orthostatic stress in persons with high and low casual blood pressure. The results suggest that abnormal opioidergic control of systolic blood pressure responses to psychological stress is not likely a result of altered baroreflex function. Persons at risk for hypertension show evidence of an opioid peptide lesion that can probably be localized either at the adrenal medullae or at levels of central autonomic control that are parallel with or rostral to baroreflex circuits.

Adolescent↗
PubMedDate not supplied

Classically conditioned enhancement of hyperinsulinemia in the ob/ob mouse.

The obese (C57BL/6J ob/ob) mouse is a commonly used animal model of non-insulin-dependent diabetes mellitus. Recent experiments have shown that stress hyperglycemia can be classically conditioned in the obese but not in the lean mouse. In the present study, classical conditioning of insulin secretion was attempted in C57BL/6J obese and lean animals. For 21 days, obese and lean mice were exposed to a conditioned olfactory stimulus prior to and during eating. On the 22nd day, blood was sampled for all animals following presentation of the conditioned stimulus; testing was repeated 2 weeks later following an additional 4 days of conditioning. Results indicated an effect of conditioning, with significantly greater plasma insulin for trained than for untrained obese mice. That insulin secretion can be more easily conditioned in the obese mouse suggests that a cholinergic mechanism may be involved in the hyperinsulinemia characteristic of this animal.

Animals↗
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Naltrexone potentiates glycemic responses during stress and epinephrine challenge in genetically obese mice.

The genetically obese mouse (C57BL/6J ob/ob) is a commonly used animal model of non-insulin-dependent diabetes mellitus. These mice show exaggerated glycemic responses during behavioral stress and adrenergic stimulation, but the precise glucoregulatory mechanisms are not well characterized. The ob/ob mice have multiple endocrine abnormalities, including elevated pituitary and circulating beta-endorphin levels; and a relationship between hyperglycemia and altered opioid function has been suspected. We now report that opiate antagonism with naltrexone potentiates hyperglycemic responses during stress and epinephrine challenge in obese mice. This effect of opioid blockade suggests that endogenous opioids inhibit stress- and epinephrine-induced hyperglycemia in the genetically obese mouse.

Animals↗
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Role of stress in the etiology and treatment of diabetes mellitus.

Stress has long been suspected as having major effects on metabolic activity. The effects of stress on glucose metabolism are mediated by a variety of "counter-regulatory" hormones that are released in response to stress and that result in elevated blood glucose levels and decreased insulin action. This energy mobilizing effect is of adaptive importance in a healthy organism. However, in diabetes, because of a relative or absolute lack of insulin, stress-induced increases in blood glucose cannot be adequately metabolized. Thus, stress is a potential contributor to chronic hyperglycemia in diabetes, although its exact role is unclear. Although there is some suggestion from retrospective human studies that stress can precipitate type I diabetes, animal studies are contradictory with different stressors either having facilitatory or inhibitory effects upon the development of the disease. Human investigations in patients with established diabetes are equally confusing with some showing that stress can stimulate hyperglycemia, hypoglycemia or have no effect at all on glycemic status. There is more consistent evidence supporting the role of stress in animal models of type II diabetes. However, human studies on the role of stress on the course of established type II diabetes are few. Intervention studies suggest that behavioral or pharmacologic intervention to manage stress may contribute significantly to diabetes treatment, but more long-term research is needed. It is concluded that further research is needed to establish the importance of behavioral factors in the etiology and management of diabetes, and several areas of methodologic improvement are suggested.

Animals↗
PubMedDate not supplied

Animal models provide insight into psychosomatic factors in diabetes.

OBJECTIVE: To review the literature regarding the use of animal models in research addressing psychosomatic aspects of diabetes. METHOD: We examine the key findings in animal model vs. human research in the area of stress and diabetes. Previous research has suggested that stress is a potential contributor to chronic hyperglycemia in diabetes. Stress affects metabolic activity via the stimulation of a variety of hormones that can result in elevated blood glucose levels. In patients with diabetes, due to a relative or absolute lack of insulin, stress-induced increases in glucose cannot be properly metabolized. Additionally, regulation of these stress hormones may be abnormal in diabetes. RESULTS: Human studies on the role of stress in the onset and course of type II diabetes are few and are limited by the constraints and logistics of examining life stress in humans. However, animal research allows for tight experimental control and the manipulation of factors that may contribute to the development and/or course of diabetes, such as stress, eating behavior, the nutrient content of food, and physical activity. Disease processes can be examined at a mechanistic level in animals which is typically limited in human research. CONCLUSIONS: There is a large body of animal work to support the notion that stress reliably produces hyperglycemia in type II diabetes. Furthermore, there is evidence that the autonomic nervous system plays a role in the pathophysiology of this condition in both animals and humans. Examination of eating behavior and nutrient content of food in animal models of diabetes has shed light on the role of these factors in the development of diabetes, as well as obesity. Finally, genetic research using animal models of diabetes will provide new directions for research in humans to delineate the genetic contribution to the development of diabetes.

Animals↗
PubMedDate not supplied

Depressed mood is a factor in glycemic control in type 1 diabetes.

OBJECTIVE: The diabetes literature contains conflicting evidence on the relationship between depression and glycemic control. This may be due, in part, to the fact that past studies failed to distinguish between patients with type 1 and type 2 diabetes. Because these are actually completely different diseases that are often treated differently and consequently make different demands on patients, the relationship between glycemic control and depressed mood in type 1 and type 2 diabetes was examined separately. METHODS: The relationship between Beck Depression Inventory (BDI) scores and HbA1c, as an index of long-term glycemic control, was measured in samples of 30 patients with type 1 and 34 patients with type 2 diabetes. RESULTS: Groups of patients with type 1 and type 2 diabetes did not differ in mean BDI score or HbA1c level. Correlation analysis revealed a significant positive relationship between BDI scores and HbA1c in the type 1 group (r = .44, p < .02) but not in the type 2 group (r = -0.06, p > .05). This relationship was evident throughout the entire range of BDI scores and was not restricted to scores indicative of clinical depression. Patients with type 1 diabetes who had higher HbA1c and BDI scores reported a lower frequency of home blood glucose monitoring. CONCLUSIONS: Variations in depressive mood, below the level of clinical depression, are associated with meaningful differences in glycemic control in type 1 but not type 2 diabetes. Preliminary data analysis suggests that this effect may be mediated, at least in part, by decreased self-care behaviors in patients with more depressed mood.

Adult↗
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Endogenous opiate peptides, stress reactivity, and risk for hypertension.

Endogenous opiate peptides can regulate neuroendocrine and circulatory responses to behavioral stress and may be important in the pathogenic effects of sympathoadrenal reactivity. We tested this hypothesis by examining the effect of the opiate antagonist naloxone on blood pressure responses to behavioral stress in young adults with high, medium, or low casual blood pressures. Naloxone increased mean arterial pressure responses to stress in subjects with low casual pressure, but had no significant effect on responses in subjects with high casual pressure. These results suggest opioidergic inhibition of sympathetic nervous system responses may be deficient in persons at risk for essential hypertension.

Adolescent↗
PubMedDate not supplied

Effects of relaxation therapy on patients with type I diabetes mellitus.

We investigated the effect of treatment with biofeedback-associated progressive muscle relaxation on 10 patients with poorly controlled type I diabetes mellitus compared with 10 equivalent untreated patients. In contrast to previous studies of patients with type II diabetes, no improvement occurred in glucose tolerance after 1 wk of intensive in-hospital relaxation training or in glycohemoglobin and total daily insulin dose after 6 wk of practicing relaxation techniques at home. This and other studies suggest that this type and amount relaxation therapy may not be as useful for enhancing blood glucose control in patients with type I diabetes as in those with type II diabetes. However, subpopulations of type I diabetic patients who have demonstrated stress-induced hyperglycemia should be further investigated.

Adult↗
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The role of behavior in diabetes care.

The treatment of people with diabetes mellitus almost always involves an effort on the part of the health-care team to impose new patterns of behavior on their patients. Too often this behavior modification is undertaken without any specific attention to factors in the treatment regimen that may enhance or detract from patient compliance. If, however, the treatment of disease is viewed in terms of changes in both physiology and behavior, the importance of intervention aimed at either direct behavioral manipulation of physiology, or alterations of secondary behavior related to the disease and its therapy, becomes apparent. We have reviewed in this paper the current "state of the art" of both direct behavioral treatment of diabetes and techniques to enhance compliance with treatment program.

Autonomic Nervous System↗
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The effects of relaxations on glucose tolerance in non-insulin-dependent diabetes.

Twelve patients with non-insulin-dependent diabetes mellitus were hospitalized on a clinical research ward under identical conditions. A 3-h glucose tolerance test and an intravenous insulin tolerance test were performed on each patient. Half of the patients were then given 5 days of progressive relaxation training after which all patients were retested while treated patients practiced relaxation. Relaxation was found to significantly improve glucose tolerance without affecting insulin sensitivity or glucose-stimulated insulin secretory activity.

Adult↗