Premium
Inhibition by atropine of the increased turnover of noradrenaline in the hypothalamus of rats exposed to cold
Author(s) -
SIMMONDS M. A.
Publication year - 1971
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1971.tb07103.x
Subject(s) - atropine , hypothalamus , chemistry , endocrinology , endogeny , medicine , hyperthermia , turnover , biology , management , economics
Summary1 Small doses of (—)‐[ 3 H] noradrenaline were injected into the lateral cerebral ventricles in rats to label radioactively the endogenous noradrenaline (NA) stores. 2 Intraventricular injection of 25 μg atropine methonitrate at the same time inhibited the increased rate of disappearance of [ 3 H] NA from the hypothalamus at an environmental temperature of 9° C, when compared with the values at 24° C, without impairing temperature regulation. 3 At 32° C, 25 μg atropine methonitrate caused a lethal hyperthermia. A dose of 5 μg was not lethal and did not inhibit the increased rate of disappearance of [ 3 H] NA from the hypothalamus. 4 It is concluded that the pathway which stimulates an increased turnover of NA in the cold contains an atropine sensitive synapse but is not the principal pathway of heat production. The increased turnover of NA in the heat probably does not involve an atropine sensitive synapse.