Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Pyrogens”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources
PubMed1987

The development of a febrile response to pyrogen in the thyroid-deficient rabbit.

The development of the febrile response to E. coli lipopolysaccharide (1.5 micrograms/kg, i.v.) in thyroid-deficient rabbits has been studied. Twenty-eight New Zealand White rabbits weighing 2.1-2.3 kg were used. Hypothyroidism was induced by treatment with propylthiouracil (100 or 200 mg/kg body wt./15 days). Thyroid-deficient animals showed a reduction in the febrile response to lipopolysaccharide, but the effect was significantly different (p less than 0.01) from the control only for rabbits treated with 200 mg/kg of propylthiouracil. Propranolol (2 mg/kg, i.p.) given 30 min before lipopolysaccharide also reduced (p less than 0.01) the fever response in control rabbits. The results of this experiment are consistent with the hypothesis that the reduction in the febrile response of thyroid-deficient rabbits is due to the reduced number of beta-adrenergic receptors, or to a change in the availability of neurotransmitter in thermogenically active tissues, such as brown fat.

Animals↗
PubMed1988

Pyrogenicity of interferon and its inducer in rabbits.

The effects of intracerebral administration of interferon (IFN) or its inducer polyriboinosinic acid-polyribocytidylic acid (poly I:C) on thermoregulatory responses were assessed in conscious rabbits. Administration of IFN (10(2)-10(6) IU) or poly I:C (0.012-12 micrograms) into the preoptic anterior hypothalamus or the third cerebral ventricle caused a dose-dependent fever in rabbits at three ambient temperatures (Ta) tested. In the cold (Ta = 8 degrees C), the fever was due to increased metabolism, whereas in the heat (Ta = 32 degrees C) the fever was due to a reduction in respiratory evaporative heat loss and ear skin blood flow. At the moderate environmental temperature (Ta = 22 degrees C), the fever was due to increased metabolism and cutaneous vasoconstriction. Compared with the febrile responses induced by cerebroventricular route injection of IFN or poly I:C, the hypothalamic route of injection required a much lower dose of IFN or poly I:C to produce a similar fever. Furthermore, the fever induced by intrahypothalamic injection of IFN or poly I:C was reduced by pretreatment of animals with a systemic dose of indomethacin (an inhibitor of all prostaglandins formation) or cycloheximide (an inhibitor of protein synthesis). The data indicate that IFN or its inducer may act through the endogenous release of a prostaglandin or a protein factor of an unknown chemical nature in the preoptic anterior hypothalamic region to induce fever in rabbits. The fever induced by IFN or its inducer is brought about by a decrease in heat loss and/or an increase in heat production in rabbits.

Animals↗