OBJECTIVE: To study the influence of sex on the responses of microvessels to vasoactive agents in experimental diabetes. MATERIALS: Diabetes was induced by alloxan (40 mg/kg, iv) in male and female Wistar rats (8-10-week-old). METHODS: Using an image splitter television microscope, mesenteric arteriolar and venular diameter changes induced by topically applied vasoactive agents (histamine, bradykinin, platelet activating factor-PAF, acetylcholine, sodium nitroprusside, noradrenaline and angiotensin II) were examined. RESULTS: Whereas the vasoconstrictor response to noradrenaline was equivalent in normal and diabetic animals, either female or male rats, an increased vasoconstrictor response to angiotensin II was observed in male but not in female diabetic rats in comparison with respective controls. Similarly to that observed in males, the dilator response of microvessels to topically applied bradykinin, histamine and PAF was impaired in female diabetic rats. Whereas reversal of the impaired responses to these agents was obtained by acute treatment of diabetic animals with insulin the altered responses to angiotensin II observed in male diabetic rats were not corrected. Differently from that observed in males, impaired response of microvessels to acetylcholine but not to sodium nitroprusside was observed in female diestrous diabetic rats; acute insulin treatment corrected it. CONCLUSIONS: We conclude that not all the alterations of the microvascular reactivity and the correction by insulin are gender dependent in diabetes.
OBJECTIVE: To study the influence of sex on the responses of microvessels to vasoactive agents in experimental diabetes. MATERIALS: Diabetes was induced by alloxan (40 mg/kg, iv) in male and female Wistar rats (8-10-week-old). METHODS: Using an image splitter television microscope, mesenteric arteriolar and venular diameter changes induced by topically applied vasoactive agents (histamine, bradykinin, platelet activating factor-PAF, acetylcholine, sodium nitroprusside, noradrenaline and angiotensin II) were examined. RESULTS: Whereas the vasoconstrictor response to noradrenaline was equivalent in normal and diabetic animals, either female or male rats, an increased vasoconstrictor response to angiotensin II was observed in male but not in female diabeticrats in comparison with respective controls. Similarly to that observed in males, the dilator response of microvessels to topically applied bradykinin, histamine and PAF was impaired in female diabeticrats. Whereas reversal of the impaired responses to these agents was obtained by acute treatment of diabetic animals with insulin the altered responses to angiotensin II observed in male diabeticrats were not corrected. Differently from that observed in males, impaired response of microvessels to acetylcholine but not to sodium nitroprusside was observed in female diestrous diabeticrats; acute insulin treatment corrected it. CONCLUSIONS: We conclude that not all the alterations of the microvascular reactivity and the correction by insulin are gender dependent in diabetes.
Authors: Nathanne S Ferreira; Stêfany B A Cau; Marcondes A B Silva; Carla P Manzato; Fabíola L A C Mestriner; Takayuki Matsumoto; Fernando S Carneiro; Rita C Tostes Journal: Front Pharmacol Date: 2015-03-02 Impact factor: 5.810
Authors: Lucas Giglio Colli; Larissa Berloffa Belardin; Cinthya Echem; Eliana Hiromi Akamine; Mariana Pereira Antoniassi; Rhayza Roberta Andretta; Lucas Solla Mathias; Stephen Fernandes de Paula Rodrigues; Ricardo Pimenta Bertolla; Maria Helena Catelli de Carvalho Journal: Sci Rep Date: 2019-07-30 Impact factor: 4.379