Faculty Collaboration Database

Diabetes attenuates the minimum anaesthetic concentration (MAC) and MAC-blocking adrenergic response reducing actions of clonidine in rats. Acta Anaesthesiol Scand 2001 Nov;45(10):1230-4

Date

12/12/2001

Pubmed ID

11736675

DOI

10.1034/j.1399-6576.2001.451010.x

Scopus ID

2-s2.0-0035167848 (requires institutional sign-in at Scopus site)   4 Citations

Abstract

BACKGROUND: It is well known that clonidine, an alpha2 agonist, reduces anaesthetic requirement and attenuates haemodynamic responses against noxious stimuli. However, the diabetic state is known to affect several functions of alpha2 adrenoceptors. We investigated the effects of streptozotocin (STZ)-induced diabetes mellitus (DM) on these beneficial actions of clonidine in halothane-anaesthetized rats.

METHODS: The rats were randomly assigned to one of three groups: diabetes (n=24, induced by 50 mg x kg(-1) IV STZ), diabetes treated with insulin (n=24), or control (n=24). We evaluated the effects of clonidine on minimum anaesthetic concentration (MAC) and minimum concentration of halothane needed to suppress cardiovascular responses evoked by a noxious stimulus (MAC-blocking adrenergic responses: MAC-BAR) in each group. MAC and MAC-BAR of halothane were determined by the tail clamp method. MAC-BAR was defined as the MAC which attenuated haemodynamic responses within 10% following the tail clamp.

RESULTS: The diabetic state decreased MAC of halothane by approximately 10%, while MAC-BAR of halothane had been little affected. In the diabetes group, MAC reducing action of clonidine (30 and 100 microg x kg(-1), IV) was completely abolished and MAC-BAR reducing action of clonidine was partially reduced (30 but not 100 microg x kg(-1), IV). Insulin treatment preserved these actions of clonidine.

CONCLUSION: It is suggested that the diabetic state attenuates the beneficial actions of clonidine and that insulin treatment of diabetes preserves these actions of clonidine.

Author List

Kita T, Kagawa K, Mammoto T, Takada K, Hayashi Y, Mashimo T, Kishi Y

Author

Tadanori Mammoto MD, PhD Associate Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adrenergic alpha-Agonists
Anesthesia, Inhalation
Anesthetics, Inhalation
Animals
Clonidine
Diabetes Mellitus, Experimental
Halothane
Hemodynamics
Insulin
Male
Pain Threshold
Rats
Rats, Sprague-Dawley