ascorbic-acid and Adrenocortical-Hyperfunction

In neurosurgery practice glucocorticoids are commonly used. Steroids may have central nervous system side effects affecting whole body, including steroid-induced mental agitation and psychosis. In experimental and clinical studies conducted by using dexamethasone (DEX), it has been reported that DEX adversely affects learning and memory skills. Unfortunately, there are yet no clinically accepted clinical approaches to prevent DEX-induced cognitive dysfunction. In this experimental study it was aimed to investigate the effect of chronic DEX administration on learning-memory and locomotor behaviors in adult male Sprague Dawley rats. In addition, it was also aimed to explore the potential favorable contribution of melatonin (MEL) and vitamin C (Vit C) having antioxidant and neuroprotective properties to the effects of DEX on learning-memory and locomotor behaviors. For this purpose, rats were injected 10mg/kg DEX intraperitoneally, both alone and in combination with MEL (40 mg/kg) and Vit C (100mg/kg), for 9 days, and the animals were tested using the radial arm maze and open field apparatus. The test results revealed that DEX caused a significant decrease in spatial memory and locomotor activities and MEL and Vit C failed to reverse losses in these activities. Furthermore, DEX led to a gradual weight loss that reached 30% of the initial weight at 9th day of the injection. DEX administration causes a generalized loss of behavioral activity of rats. Experimental studies devised to investigate effects of DEX should take into account this DEX-induced generalized behavioral loss when assessing the effects of DEX on learning and memory skills. This article is part of a Special Issue entitled SI: Brain and Memory.

Topics: Adrenocortical Hyperfunction; Animals; Antioxidants; Ascorbic Acid; Cholinergic Antagonists; Dexamethasone; Disease Models, Animal; Dose-Response Relationship, Drug; Exploratory Behavior; Glucocorticoids; Male; Maze Learning; Melatonin; Memory Disorders; Motor Activity; Rats; Rats, Sprague-Dawley; Scopolamine; Statistics, Nonparametric; Time Factors

The effect of hypoxia, exercise, and thermal stress on myocardial metabolism have been widely investigated, but little attention has been paid to studying the effects of a combination of these stress. The influence of hypoxia as modified by physical exertion (swimming) and cold stress was therefore studied. The parameters investigated included myocardial glycogen and noradrenaline, serum free fatty acid, adrenal ascorbic acid, and adrenal weight. It was observed that maximal stress was produced when hypoxia was combined with physical exertion. No suppression of cold-induced lipolysis by hypoxia was observed, in contrast to previously reported observations. Maximal depletion of cardiac blycogen and cardiac noradrenaline was noted in hypoxic exercise. Adrenal overactivity was not found to be related to any particular stress but was seen to be proportional to the severity of the stress applied.

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Cold Temperature; Fatty Acids, Nonesterified; Glycogen; Hypoxia; Lipid Metabolism; Male; Myocardium; Norepinephrine; Organ Size; Physical Exertion; Rats; Stress, Physiological

Topics: Acidosis; Adrenocortical Hyperfunction; Ascorbic Acid; Ascorbic Acid Deficiency; Peptic Ulcer; Postoperative Care; Postoperative Complications; Preoperative Care

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Animals, Newborn; Ascorbic Acid; Corticosterone; Female; Organ Size; Pituitary-Adrenal Function Tests; Pregnancy; Rats; Stress, Physiological

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Cholesterol; Dexamethasone; Hydrocortisone; Hypertrophy; Hypothalamo-Hypophyseal System; Hypothalamus; Male; Organ Size; Pituitary Gland; Pituitary-Adrenal System; Rats

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Body Weight; Carbon Tetrachloride Poisoning; Female; Hypertrophy; Organ Size; Rats

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Fasting; Protein Deficiency; Rats

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Atrophy; Diet; Drug Antagonism; Hypertrophy; Male; Rats; Testis; Tyrosine

Topics: Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Blood Chemical Analysis; Cortisone; Diabetes Mellitus, Experimental; Female; Rats

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Cholesterol; Lipid Metabolism; Rats; Reserpine

Topics: Adrenal Cortex; Adrenocortical Hyperfunction; Ascorbic Acid; Cholesterol; Ethionamide; Isoniazid; Pharmacology; Pyridoxine; Rats; Research; Toxicology

Topics: Adrenal Glands; Adrenocortical Hyperfunction; Animals; Ascorbic Acid; Cholesterol; Diabetes Mellitus, Experimental; Histocytochemistry; Hypertrophy; Lipids; Rats

Topics: Adrenal Glands; Adrenal Insufficiency; Adrenocortical Hyperfunction; Adrenocorticotropic Hormone; Animals; Ascorbic Acid; Corticosterone; Dogs; Humans; Hydrocortisone; Hypophysectomy; Rats; Steroids