Evidence for separate mechanisms of induction of biphasic fever inside and outside the blood-brain barrier in rabbits.

AUTOR(ES)

Morimoto, A

RESUMO

1. Intravenous bacterial endotoxin, or endogenous pyrogen, in high concentration both caused biphasic fever in rabbits. In low concentration they produced only the first phase of fever. 2. Subcutaneous indomethacin suppressed the first phase of fever produced by high concentration of intravenous endotoxin or endogenous pyrogen, but not the second phase. 3. Intraventricular cerebral injection of indomethacin reduced the second phase of fever produced by high concentration of intravenous endotoxin or endogenous pyrogen, but not the first phase. 4. Intraventricular cerebral injection of endotoxin or of endogenous pyrogen caused slow monophasic fever. This was suppressed by intraventricular, but not by subcutaneous, indomethacin. 5. It is concluded that the first phase of biphasic fever is caused by pyrogen acting via structures outside the blood-brain barrier, presumably peripheral nerves, and the second phase by pyrogen acting via structures within the blood-brain barrier, presumably hypothalamic neurones.

Documentos Relacionados

• Separate mechanisms inside and outside the blood—brain barrier inducing metabolic changes in febrile rabbits
• Blood—Brain Barrier
• Blood—Brain Barrier
• The Blood-Brain Barrier and Neurotherapeutics
• Effect of osmotic blood-brain barrier disruption on gentamicin penetration into the cerebrospinal fluid and brains of normal rabbits.