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Published on: July 29, 2014
Effects of diabetes on the morphine-induced Straub tail reaction in mice
1Department of Pharmacology, Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo, Japan.
Abstract:
The effects of diabetes on the morphine-induced Straub tail reaction were examined in mice. The Straub tail reaction induced by s.c. administration of morphine was significantly less in diabetic mice than in non-diabetic mice. The morphine-induced Straub tail reaction was significantly reduced following pretreatment with beta-funaltrexamine, a selective mu-opioid receptor antagonist, in both diabetic and non-diabetic mice. Furthermore, the morphine-induced Straub tail reaction was also significantly reduced in both diabetic and non-diabetic mice following pretreatment with naloxonazine, a selective mu1-opioid receptor antagonist. These results suggest that mice with diabetes are hypo-responsive to mu1-opioid receptor-mediated Straub tail reaction.
Insights
Diabetic mice show a reduced response to morphine, specifically in the Straub tail reaction. This suggests diabetes impairs the mu1-opioid receptor pathway involved in this morphine effect.
Area of Science:
- Pharmacology
- Neuroscience
- Diabetes Research
Background:
- The Straub tail reaction is a common model for studying opioid receptor activity.
- Diabetes mellitus is known to affect various physiological systems, including the nervous system.
Purpose of the Study:
- To investigate the impact of diabetes on the morphine-induced Straub tail reaction in mice.
- To determine the role of specific opioid receptor subtypes in this altered response.
Main Methods:
- Induction of diabetes in a mouse model.
- Administration of morphine to induce the Straub tail reaction.
- Pretreatment with selective mu-opioid receptor antagonists (beta-funaltrexamine and naloxonazine).
- Quantification and comparison of the Straub tail reaction in diabetic and non-diabetic mice.
Main Results:
- Diabetic mice exhibited a significantly diminished Straub tail reaction compared to non-diabetic controls.
- Pretreatment with beta-funaltrexamine (mu-opioid antagonist) reduced the reaction in both groups.
- Pretreatment with naloxonazine (mu1-opioid antagonist) also significantly reduced the reaction in both diabetic and non-diabetic mice.
Conclusions:
- Diabetes induces hypo-responsiveness to morphine's effect on the Straub tail reaction.
- The mu1-opioid receptor pathway is implicated in the reduced response observed in diabetic mice.
- These findings highlight potential alterations in opioid signaling in diabetes.
