Acute and Chronic Effects of Preoptic Lesions

Autor: B. Hökfelt, B. Anderson, C. C. Gale, Börje Larsson
Rok vydání: 1965
Předmět:
Zdroj: Acta Physiologica Scandinavica. 65:45-60
ISSN: 1365-201X
0001-6772
DOI: 10.1111/j.1748-1716.1965.tb04248.x
Popis: Anderson, B., C. C. Gale, B. Hokfelt and B. Larsson. Acute and chronic effects of preoptic lesions. Acta physiol. scand. 1965, 65, 45–60. — The effects of preoptic and preoptic/hypothalamic lesions were studied in unanesthetized goats. A gradual destruction of the entire preoptic region (the “heat loss center”) was induced by proton irradiation in two animals. The lesions caused a permanently raised heat-dissipation threshold, an impaired resistance to cold, a complete adipsia and a lack of thermal inhibition of food intake. A febrile response to pyrogen was obtained in spite of the destruction of the preoptic region. In contrast to the proton lesions a rapidly induced radio-frequency (RF) coagulation was fatal if restricted to the preoptic region. It caused initial strong shivering and peripheral vasoconstriction, sympathico-adrenomedullary and thyroid activation, severe hyperthermia, hyperglycemia, and death within 16 hours in three goats studied. An ability to respond to severe hyperthermia with polypnea remained in these goats. In two goats preoptic RF-lesions were extended to involve most of the anterior hypothalamus. These animals survived an initial period of hyperthermia and sympathico-adrenomedullary activation. One of them was studied for 8 months and showed similar disturbances of temperature regulation and alimentation as the proton irradiated goats. In one goat the RF lesions was extended further caudally to involve also the mid-hypothalamic region. The immediate effects were virtual disappearance of urinary excretion of noradrenaline development of marked hypothermia, and considerable hypoglycemia.
Databáze: OpenAIRE
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