Nonenzymatic fibrinolytic reaction to the intravenous administration of small doses of Salmonella endotoxin to rabbits

Intravenous injection of a low dose of Salmonella endotoxin (10 micrograms/kg bw) into rabbits results in an increase in the non-enzymatic fibrinolytic activity of blood at early stages of a pathological process followed by depression of this response at later stages of the pathology. At higher degrees of non-enzymatic fibrinolysis activation the morphological and ultrastructural changes in renal tissues caused by endotoxin injection are the least pronounced. Intravenous injection of heparin after injection of a lethal dose of Salmonella endotoxin (100-200 micrograms/kg) enhances non-enzymatic fibrinolysis activation and decreases the morphological and ultrastructural lesions in renal tissues.     

Effect of pharmacological doses of oxytocin on insulin response to glucose in normal man

In this study we have examined the effect of the administration of oxytocin on basal blood concentrations of insulin, glucagon, cortisol, growth hormone, and on the dynamic secretory response of these hormones to intravenous glucose administration (0.33 g/kg) in basal condition and after the injection of 3 IU (1 plus 2 IU/1 h) or 6 IU (2 plus 4 IU/1 h) of oxytocin (6 subjects for each group). The highest dose of oxytocin (6 IU) used significantly increased insulin secretion in response to intravenously administered glucose. No significant change of insulin secretion was observed with 3 IU of oxytocin. Glucagon, cortisol, and growth hormone response to intravenous injection of glucose was not affected by oxytocin (3 or 6 IU) administration. These results suggest that high doses of oxytocin affect beta-cell function in normal man.     

Adrenal modulation of the inhibitory effect of corticotropin releasing factor on feeding

Corticotropin releasing factor (CRF) reduces food intake in rats after central administration. In these studies we examined whether the adrenal gland and the vagus were involved in CRF suppression of intake. One hour intake was reduced by a 5 μg (ICV) injection of CRF in sham but not adrenalectomized rats maintained on 0.9% NaCl. In a separate experiment on rats maintained on tap water, the inhibitory effect of CRF (5 μg) lasted at least 4 hours in sham rats whereas adrenalectomized rats did not significantly differ from controls. These experiments suggest that the adrenal gland modulates the feeding response to CRF. As replacement with corticosterone (0.75 mg/kg) in total adrenalectomized rats did not restore responsiveness to 5 or 10 μg of CRF, we next studied whether the adrenal medulla was responsible for the decreased responsiveness to CRF. In rats lacking the adrenal medulla only, food intake was reduced by a 5 μg injection of CRF; in sham rats, intake was significantly reduced by doses as low as 0.1 μg of CRF. An additional experiment examined the effect of gastric vagotomy on the CRF feeding response. Vagotomized rats were as responsive to 5 and 10 μg injections of CRF as sham rats, which suggests that the effect is not dependent on the vagus nerve. These findings indicate that the adrenal gland, primarily the medulla, plays an intermediate role in the reduction of food intake caused by central injections of CRF. This conclusion is consistent with the known effect of CRF on adrenomedullary discharge.     

Prolactin response to beta-endorphin in man

Beta endorphin was administered intravenously to six medication-free schizophrenic patients under placebo-controlled conditions. Serum prolactin (PRL) and growth hormone (GH) concentrations were measured for 90 minutes after infusion. Prolactin was significantly increased following beta-endorphin infusion compared to placebo infusions. Growth hormone levels were not affected by beta-endorphin. The implications of the PRL response in schizophrenic patients await further study.