Turkish Journal of Medical Sciences
Abstract
Background/aim: Menopause is associated with increased vascular risk. This study investigated the effects of 3 centrally acting muscle relaxants—tizanidine (TZ), thiocolchicoside (TCC), and cyclobenzaprine (CBZ)—on vascular reactivity in ovariectomized (OVX) rats as a model of menopause.
Materials and methods: Body weight, blood glucose, blood pressure, and heart rate were recorded, and the rats underwent oophorectomy surgery. Eight weeks after the operation, the rats were divided into 5 groups: sham operated rats, OVX rats, OVX rats treated with TZ (OVX + TZ), OVX rats treated with TCC (OVX + TCC), and OVX rats treated with CBZ (OVX + CBZ). All drug treatments were at a dosage of 2 mg/kg/day for 2 weeks. Isolated rat aortas were suspended in a tissue chamber. Vascular reactivity was assessed using increasing concentrations of phenylephrine, acetylcholine, and sodium nitroprusside, as well as potassium chloride at a concentration of 40 mM.
Results: Body weight, phenylephrine sensitivity, and potassium chloride responses significantly increased with OVX. TZ and CBZ decreased body weight gain and ameliorated receptor-dependent contractile sensitivity. TZ and CBZ had calcium antagonistic effects on vascular smooth muscle. TZ deteriorated endothelial function.
Conclusion: TZ cannot be considered a safe medication for patients with endothelial dysfunction. In high doses and for longer periods, TCC and CBZ might also have deleterious effects on vascular reactivity. These findings are noteworthy from the perspective of rational drug therapy.
Author ORCID Identifier
SÜMEYYE NUR GÜRSOY: 0000-0001-6295-5759
TOLGA ESMERLİGİL: 0000-0001-9824-3673
UĞUR BERKAY İNCE: 0009-0009-4024-6359
TURHAN DOST: 0000-0001-7547-3310
BUKET DEMİRCİ: 0000-0002-3442-5061
DOI
10.55730/1300-0144.6115
Keywords
Endothelium, Menopause, muscle relaxant, pain control, rational drug therapy
First Page
1569
Last Page
1575
Publisher
The Scientific and Technological Research Council of Türkiye (TÜBİTAK)
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
GÜRSOY, S, ESMERLİGİL, T, İNCE, U, DOST, T, & DEMİRCİ, B (2025). The impact of tizanidine, thiocolchicoside, and cyclobenzaprine on vascular function in ovariectomized rats. Turkish Journal of Medical Sciences 55 (6): 1569-1575. https://doi.org/10.55730/1300-0144.6115
