Excessive Body Weight Gain Research Articles

Anterior ischemic optic neuropathy after open heart operations

The overall incidence of anterior ischemic optic neuropathy after open heart operations at the Lahey Clinic is less than 0.5%. However, during the 2-year period, March 1, 1990, to March 1, 1992, an increased incidence (8 of 602 patients or 1.3%) of this complication was observed. A rigorous analysis was conducted of all 602 patients who underwent operation during this period. No preoperative risk factors were identified. The development of anterior ischemic optic neuropathy was associated with prolonged cardiopulmonary bypass time, low hematocrit levels, excessive perioperative body weight gain, and the use of epinephrine and amrinone. Other hypothetical risk factors include systemic hypothermia, anemia, increased intraocular pressure, and microembolization. Treatment options include the use of corticosteroid medications, reduction of intraocular pressure, and optic nerve fenestration, although recent evidence and our experience indicate that the fenestration procedure is of no benefit. Because all methods of treatment have had limited success, efforts to prevent this complication are of paramount importance.

Effect of Cilazapril on Hyperdipsia in Hemodialyzed Patients

To investigate whether angiotensin-converting enzyme inhibitor (ACE-I) potentially alleviates hyperdipsia, the effect of cilazapril on dialysis-associated excessive thirst was studied by evaluating various dipsogenic parameters in patients undergoing chronic hemodialysis (HD) who manifest an excessive interdialysis body weight gain of more than 5%, and show simultaneous severe-to-moderate hyperdipsia. An initial single dose of 1 mg of cilazapril given at the end of the HD session produced a marked improvement in the interdialysis thirst scores and a simultaneous reduction in plasma angiotensin II (AII) concentration due to the inhibition of ACE activity. The interdialysis body weight gain in the cilazapril treatment period was significantly smaller than that in the nontreatment period. None of the other parameters including blood pressure, plasma osmolarity, and serum Na and K concentration were different in the treatment vs. the nontreatment period. The present data help to explain the potential pharmacological action of AII in the physiology of thirst and suggest that cilazapril may effectively alleviate dialysis-associated hyperdipsia at least on some occasions. The mechanism by which ACE-I exerts an antidipsogenic action may, in part, be accounted for by the reduction in plasma concentration of AII, as a result of the ACE inhibition.

Effects of chronic amitriptyline and desipramine on food intake and body weight in rats

Long-term treatment with tricyclic antidepressant drugs (TCAs) can induce excessive body weight gain in a significant proportion of patients. Such weight gains, which appear to be largely independent of clinical improvement, are in many cases severe enough to interfere with continuation of treatment. In efforts to model this effect in experimental animals, seven experiments were performed in which two commonly used TCAs, amitriptyline and desipramine, were administered chronically to rats. Despite manipulations of drug dosages (2.5 mg−17 mg/kg), route of administration (intraperitoneal, subcutaneous, oral; daily injections vs. continuous release from osmotic pumps), diet composition and palatability (regular Purina Chow pellets or powder with or without added high fat and high carbohydrate sources; high vs. low protein diets) and animal sex and housing conditions (single vs. group housing), chronic TCA treatment was never observed to increase daily food intake or rates of body weight gain. Desipramine treatment invariably caused decreased food intake and weight loss. Amitriptyline treatment either caused no change in food intake and body weight or slightly reduced levels in comparison to vehicle-treated controls. However, both amitriptyline- and desipramine-treated rats showed a potentiation of acute caloric intake after a single systemic injection of the glucoprivic agent 2-deoxy-D-glucose. These results are considered against the background of human clinical observations. Possible reasons for the differences between human and animal data are discussed.

Stimulation Lighting of Meat-Type Pullets

Meat-type pullets of two strains, housed in windowless floor pens, were subjected to two stimulation lighting treatments beginning at 140 days of age. The treatments provided increases in photoperiod from 6 to 16 hr/day by either 1) 5 increases of 2 hr/day each week or 2) increases each of 2 and 1 hr/day followed by 14 increases of .5 hr/day each week.Overall, there was no significant difference due to lighting treatment in number of hatching eggs per hen housed. However, age at 50% production was 6.3 days less; percentage hen day egg production was higher, 56.2 vs. 54.2; and egg weight was .8 g lower for hens of Treatment 1 vs. Treatment 2. For the strain with lower egg size, the number of additional eggs obtained for Treatment 1 was no greater than losses due to undersized eggs. For the strain with higher egg size, Treatment 1 prevented excess body weight gain and permitted earlier egg production.The merits of using rapid vs. slow stimulator lighting procedures for meat-type birds depend on the egg; and body weight characteristics of the strain of hen.

A simpler retractable wire knife

A detailed description is presented for the construction of a simple and inexpensive retractable wire knife and holder/adjuster for stereotaxically placed transections of neural pathways. The accuracy and reliability of the knife are supported by experimental data demonstrating the ability of bilateral parasagittal hypothalamic knife cuts to induce excessive food intake and body weight gain in female rats.

Plasma Growth Hormone and Insulin During Early Lactation in Cows Fed Silage Based Diets

Peripheral plasma insulin, growth hormone, and blood glucose were determined in 24 dairy cows during early lactation. Blood samples were obtained at 4-day intervals during the first 56 days of experimental lactations 1 and 3 of a 3-lactation experiment. The cows were divided equally among three groups and fed one of the following forage rations for three consecutive lactations: corn silage (18.2kg/day) plus alfalfa-timothy hay ad libitum; corn silage (18.2kg/day) plus alfalfa-timothy silage ad libitum; or corn silage ad libitum. These diets were continued throughout the intervening dry periods except in the latter group where corn silage intake was limited if individual animals exhibited excessive body weight gain. Four animals in each group received prepartum supplemental concentrates. The remaining four animals received no prepartum concentrate supplementation. Following parturition, concentrates were fed in increasing amounts to a maximum of 14.6 kg/day during the first 56 days of lactation. Plasma insulin, growth hormone, and blood glucose were not affected by forage diet or prepartum supplemental concentrate feeding. Plasma insulin and blood glucose increased and plasma growth hormone decreased with time after parturition. These changes were correlated with nutrient intake which increased during the experiment. Changes in plasma insulin and growth hormone are related to metabolic adjustments during early lactation.