Decreased Ca2+ influx into the endothelium contributes to the decrease in endothelium-dependent relaxation in the aorta of streptozotocin-induced diabetic mice.

K Kamata; M Sugiura; Y Kasuya

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PubMed · 8581350

Decreased Ca2+ influx into the endothelium contributes to the decrease in endothelium-dependent relaxation in the aorta of streptozotocin-induced diabetic mice.

K Kamata·M Sugiura·Y Kasuya

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Abstract

Experiments were designed to investigate the role of Ca2+ influx into the endothelium in the relaxation of mouse aorta caused by acetylcholine (ACh) in streptozotocin (STZ)-induced diabetic and age-matched control mice. When Ca2+ was added to the bath, Ca2+ caused a transient contraction followed by relaxation in Ca(2+)-free medium containing 2 x 10(-6) M prostaglandin F2 alpha (PGF2 alpha) and 10(-5) M ACh in the control experiments. On the other hand, Ca2+ showed a long lasting contraction in STZ-induced diabetic rats. These results suggest that influx of Ca2+ into the endothelium is significantly attenuated in the diabetic vessels, and production or release of relaxing factor is markedly decreased.

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Acetylcholine Animals Aorta, Thoracic Calcium Diabetes Mellitus, Experimental Dinoprost Endothelium, Vascular In Vitro Techniques Male Mice Mice, Inbred ICR Muscle Relaxation Muscle, Smooth, Vascular Rats Journal Article Research Support, Non-U.S. Gov't

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K Kamata, M Sugiura, Y Kasuya. 1995. Decreased Ca2+ influx into the endothelium contributes to the decrease in endothelium-dependent relaxation in the aorta of streptozotocin-induced diabetic mice.. https://pubmed.ncbi.nlm.nih.gov/8581350/

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