beta-endorphin and Vomiting

The purpose of this study was to determine the effects of normal human aging on the hypothalamic-pituitary-adrenocortical (HPA) axis response to the centrally active cholinesterase inhibitor physostigmine. This drug stimulates the HPA axis at a suprapituitary level by increasing central nervous system (CNS) cholinergic activity.. Plasma ACTH, beta-endorphin (beta E) and cortisol responses to a 10-minute infusion of physostigmine (.0125 mg/kg) were compared between groups of 10 normal older subjects (71 +/- 2 years [mean +/- SEM]) and 9 normal young subjects (27 +/- 2 years). Plasma physostigmine concentrations were measured to assess the comparability of the pharmacologic stimulus between groups.. Endocrine responses were substantially greater in older subjects than young subjects for ACTH (p < .01), beta E (p < .01) and cortisol (p < .01). Plasma physostigmine concentrations did not differ between older and young subjects.. This study demonstrated increased HPA axis responsivity to a CNS cholinergic stimulus in normal human aging.

Topics: Adrenocorticotropic Hormone; Adult; Aged; Aging; beta-Endorphin; Blood Pressure; Female; Heart Rate; Humans; Hydrocortisone; Hypothalamo-Hypophyseal System; Male; Nausea; Physostigmine; Pituitary-Adrenal System; Sex Factors; Vomiting

Topics: Animals; beta-Endorphin; Digestive System; Dogs; Macaca mulatta; Prostaglandins; Radiation Injuries, Experimental; Vomiting

The prodromal syndrome of radiation sickness is characterized by nausea and vomiting but the pathophysiology and the treatment of this entity is largely unknown. We investigated this problem by determining the effects of ionizing radiation on gastric function with and without administration of the dopamine antagonist domperidone. We measured gastric electrical control activity (waves per minute), fractional emptying rate (percent per minute), acid output (microequivalents per minute), and plasma levels of immunoreactive beta-endorphin. Twelve conscious, chair-adapted rhesus monkeys were studied twice before, once immediately after, and once 2 days after a single 800-cGy (800 rads) 60Co total body irradiation. In addition to causing vomiting, total body irradiation transiently suppressed gastric electrical control activity, gastric emptying and gastric secretion, while increasing plasma levels of immunoreactive beta-endorphin. Domperidone had no effect on vomiting or gastric function either before or after irradiation, but it significantly increased plasma immunoreactive beta-endorphin.

Topics: Animals; beta-Endorphin; Domperidone; Electrophysiology; Endorphins; Fasting; Gastric Emptying; Gastric Juice; Gastrointestinal Motility; Macaca mulatta; Radiation Injuries, Experimental; Vomiting; Whole-Body Irradiation

The endogenous opiate-like peptides, beta-endorphin, methionine- and leucine-enkephalin have been investigated in unanaesthetized cats after intracerebroventricular injection. beta-Endorphin produced marked and prolonged psychomotor stimulation (restlessness, apprehension, looking around, vacant stare and impelling locomotion), accompanied by pupillary dilation and tremor which was prevented by nalorphine. In contrast to beta-endorphin, the enkephalins did not cause affective behavioural phenomena. However, the enkephalins evoked transient and inconsistent vomiting which was also prevented by nalorphine. It is apparent, therefore, that morphinomimetic brain peptides are involved in at least two functions in the central nervous system: beta-endorphin subserves the mediation of a long-lasting psychomotor stimulation, while the enkephalins mediate vomiting of a transient character.

Topics: Akathisia, Drug-Induced; Animals; beta-Endorphin; Cats; Endorphins; Enkephalin, Leucine; Enkephalin, Methionine; Enkephalins; Female; Humans; Male; Nalorphine; Receptors, Opioid; Vomiting