Multiparametric Monitoring of Dose-Dependent Medetomidine Effects on Metabolic Homeostasis and Physiological Responses in Rattus norvegicus: A Study on Anesthesia Protocol Optimization

Document Type : Original Article

Authors
Seyedeh Ommolbanin Ghasemian 1
Behnam Pedram 2
Sara Afsharnejhad 2
1 Department of Veterinary, Behbahan Branch, Islamic Azad University, Behbahan, Iran
2 1. Department of Veterinary Medicine, Sho.C., Islamic Azad University, Shoushtar, Iran.
10.22034/ijvcs.2026.15100.1106
Abstract
The development of safe sedation and anesthesia methods in laboratory models serves as a cornerstone of modern biological research. Medetomidine, as a highly selective α2 adrenergic receptor agonist, is widely utilized in veterinary medicine; however, the use of optimal doses that minimize organ toxicity in the rat model requires precise investigation. This study aimed to systematically evaluate the dose-dependent effects of medetomidine on the physiological and biochemical profile of laboratory rats. In this experimental study, 24 adult male rats were randomly divided into four groups (Control, and those receiving 30, 60, and 100 μg/kg of medetomidine). Forty-eight hours post-intervention, physiological parameters (heart rate and body temperature) and serum biochemical markers (BUN, creatinine, AST, ALT, ALP, calcium, and phosphorus) were measured. The results indicated a dose-dependent decrease in heart rate (P≤0.05), whereas body temperature showed no significant change (P>0.05). Furthermore, the dose of 100 μg/kg led to a significant increase in liver enzymes, BUN, and creatinine levels, alongside a disruption in calcium and phosphorus homeostasis (P≤0.05). These findings suggest that although medetomidine provides favorable sedative effects, high doses in rats can be associated with hepatorenal toxicity. Therefore, to optimize anesthesia protocols and reduce confounding variables, the use of the minimum effective dose and rigorous monitoring of organ function are strongly recommended in future studies.
Keywords
Medetomidine
Rat Model
Hepatorenal Toxicity
Physiological Responses
Anesthesia Optimization
Subjects
1.     Akbar M, Khan A, Ali S. Effects of different doses of medetomidine in dogs. J Vet Sci. 2014;15(2):234-240.
2.     Ambrisko TD, Hikasa Y, Sato K. Influence of medetomidine on stress-related neurohormonal and metabolic effects caused by butorphanol, fentanyl, and ketamine administration in dogs. Am J Vet Res. 2005;66(3):406-412.
3.     Bishit B, Sharma A, Kumar S. Physiological and hemato-biochemical effects of dexmedetomidine in dogs. Vet Clin Pathol. 2016;45(3):412-420.
4.     Colman A, Lonnell C, Hultgren J. Effects of xylazine, romifidine or detomidine on haematological, biochemical and splenic parameters. J Vet Pharmacol Ther. 2014;37(4):380-388.
5.     Fahlman A, Arnemo JM, Swenson JE, Pringle J, Brunberg S, Nyman G. Physiologic evaluation of capture and anesthesia with medetomidine–zolazepam–tiletamine in brown bears (Ursus arctos). J Zoo Wildl Med. 2011;42(1):1-11.
6.     Gaidin SG, Petrova EA, Ivanov IV. Activation of alpha-2 adrenergic receptors stimulates GABA release by astrocytes. Glia. 2020;68(6):1114-1130.
7.     Girard A, Desmonts C, Rault D. Sedative effects of intravenous medetomidine in healthy dogs. Vet Anaesth Analg. 2010;37(2):150-158.
8.     Grimm KA, Lamont LA, Tranquilli WJ, Greene SA, Robertson SA. Veterinary Anesthesia and Analgesia. Wiley-Blackwell; 2015.
9.     Grymsrud L, Amundsen E, Olsen T. Evaluation of the effects of medetomidine in horses. J Equine Vet Sci. 2012;32(5):280-286.
10.  Kanda T, Hikasa Y. Neurohormonal and metabolic effects of medetomidine compared with xylazine in healthy cats. Can J Vet Res. 2008;72(3):278.
11.  Kirihara Y, Hamada M, Nakajima T. Effects of an anesthetic mixture of medetomidine, midazolam, and butorphanol and antagonism by atipamezole in rabbits. Exp Anim. 2019;68(3):329-336.
12.  Kullmann A, Grandy J, Holland M. Effects of xylazine, romifidine, or detomidine on hematology, biochemistry, and splenic thickness in healthy horses. Can Vet J. 2014;55(4):334.
13.  Mosallanejad B, Ghadiri A, Avizeh R. Comparative study of medetomidine, dexmedetomidine and acepromazine in dogs. J Vet Res. 2020;75(2):145-155.
14.  Murahata Y, Hikasa Y. Comparative diuretic effects of medetomidine and xylazine in cats. J Vet Med Sci. 2012;74(8):980-985.
15.  Musavi SM, Nabipour A, Jafari H. Comparative study of Xylazine and Tramadol on biochemical factors in rabbits. J Vet Res. 2019;74(3):301-309.
16.  Pleyers T, Niel L, Gouttefangeas C. Investigation of selected respiratory effects of (dex)medetomidine in healthy Beagles. Vet Anaesth Analg. 2020;47(5):667-671.
17.  Siegenthaler J, Bieri R, Spadavecchia C. Effect of medetomidine, dexmedetomidine, and their reversal with atipamezole on the nociceptive withdrawal reflex in Beagles. Animals. 2020;10(7):1240.
18.  Sinclair MD. A review of the physiological effects of alpha2-agonists. Can Vet J. 2003;44(11):885-897.
19.  Virtanen R, Savola JM, Saano V, Nyman L. Characterization of the selectivity, specificity and potency of medetomidine. Eur J Pharmacol. 1988;150(1-2):9-14.
20.  Yaygingül R, Belge A. The comparison of clinical and cardiopulmonary effects of xylazine, medetomidine and detomidine in dogs. Ankara Üniv Vet Fak Derg. 2018;65(3):313-322.
21.  Yusuf ZB, Adamu S, Abdulkadir I. Effects of medetomidine and thiopentone anaesthesia on the haematological and some serum biochemical changes in donkeys (Equus asinus) in Maiduguri, Nigeria. Niger Vet J. 2018;39(1):51-56.
Iranian Journal of Veterinary Clinical Sciences
Volume 20, Issue 1 - Serial Number 34
Spring &Summer 2026
September 2026
Pages 93-101