Sexual dimorphism in vasopressin-induced contraction of rat aorta.

Title

Sexual dimorphism in vasopressin-induced contraction of rat aorta.

Creator

Stallone J N; Crofton J T; Share L

Publisher

The American journal of physiology

Date

1991
1991-02

Description

Previously, we reported that, in the rat, pressor responsiveness to vasopressin (VP) is higher in males than in females during most phases of the estrous cycle. To explore the role of the vasculature in this phenomenon, we examined vascular reactivity to VP in thoracic aortas of male rats and female rats during each phase of the estrous cycle. Aortic rings were prepared from age-matched male and female Sprague-Dawley rats and mounted for isometric tension recording. Maximal response of female aortas to VP (4,246 +/- 163 mg/mg ring dry wt) was more than twice (P less than 0.001) that of male aortas (1,877 +/- 215 mg/mg ring wt). Sensitivity of female aortas to VP was substantially higher (P less than 0.001) than that of male aortas (EC50: 10.9 +/- 0.7 vs. 19.0 +/- 1.6 nM, respectively). Maximal rate of tension development (dT/dtmax) during contraction with VP was nearly twofold higher (P less than 0.01) in female aortas (536 +/- 23 mg/min) than in male aortas (300 +/- 19 mg/min). Maximal response, sensitivity, and dT/dtmax of female aortas did not vary significantly during the estrous cycle. Maximal response of female aortas to phenylephrine (PE; 1,251 +/- 93 mg/mg ring wt) was half that (P less than 0.001) of male aortas (2,546 +/- 194 mg/mg ring wt); sensitivity to PE did not differ significantly (EC50: 0.33 +/- 0.02 vs. 0.38 +/- 0.06 microM, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Subject

*Sex Characteristics; *Vasoconstriction; Animals; Aorta/*drug effects; Arginine Vasopressin/*pharmacology; Dose-Response Relationship; Drug; Female; Male; Osmolar Concentration; Phenylephrine/pharmacology; Rats

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

H453–458

Issue

2

Volume

260

Citation

Stallone J N; Crofton J T; Share L, “Sexual dimorphism in vasopressin-induced contraction of rat aorta.,” NEOMED Bibliography Database, accessed August 4, 2021, https://neomed.omeka.net/items/show/4608.

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