Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats
Abstract Nitric oxide (NO) contributes to blood pressure (BP) regulation via its vasodilatory and anti‐inflammatory properties. We and others previously reported sex differences in BP in normotensive and hypertensive rat models where females have lower BP than age‐matched males. As females are known...
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| Format: | Article |
| Language: | English |
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Wiley
2023-08-01
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| Series: | Physiological Reports |
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| Online Access: | https://doi.org/10.14814/phy2.15771 |
| _version_ | 1797397542702415872 |
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| author | Ahmed A. Elmarakby Karim M. Saad G. Ryan Crislip Jennifer C. Sullivan |
| author_facet | Ahmed A. Elmarakby Karim M. Saad G. Ryan Crislip Jennifer C. Sullivan |
| author_sort | Ahmed A. Elmarakby |
| collection | DOAJ |
| description | Abstract Nitric oxide (NO) contributes to blood pressure (BP) regulation via its vasodilatory and anti‐inflammatory properties. We and others previously reported sex differences in BP in normotensive and hypertensive rat models where females have lower BP than age‐matched males. As females are known to have greater NO bioavailability than age‐matched males, the current study was designed to test the hypothesis that anesthetized female normotensive Wistar Kyoto rats (WKY) are more responsive to acute NOS inhibition‐induced increases in BP compared to male WKY. Twelve‐week‐old male and female WKY were randomized to infusion of the nonspecific NOS inhibitor NG‐nitro‐L‐arginine methyl ester (L‐NAME, 1 mg/kg/min) or selective NOS1 inhibition with vinyl‐L‐NIO (VNIO, 0.5 mg/kg/min) for 60 min. Mean arterial BP, glomerular filtration rate (GFR), urine volume, and electrolyte excretion were assessed before, and during L‐NAME or VNIO infusion. L‐NAME and VNIO significantly increased BP in both sexes; however, the increase in BP with L‐NAME infusion was greater in females versus males compared to baseline BP values. Acute infusion of neither L‐NAME nor VNIO for 60 min altered GFR in either sex. However, urine volume, sodium, chloride and potassium excretion levels increased comparably in male and female WKY with L‐NAME and VNIO infusion. Our findings suggest sex differences in BP responses to acute non‐isoform‐specific NOS inhibition in WKY, with females being more responsive to L‐NAME‐induced elevations in BP relative to male WKY. However, sex differences in the BP response did not coincide with sex differences in renal hemodynamic responses to acute NOS inhibition. |
| first_indexed | 2024-03-09T01:12:33Z |
| format | Article |
| id | doaj.art-52370cb3a48942ad92c9c1b5f1cdec7b |
| institution | Directory Open Access Journal |
| issn | 2051-817X |
| language | English |
| last_indexed | 2024-03-09T01:12:33Z |
| publishDate | 2023-08-01 |
| publisher | Wiley |
| record_format | Article |
| series | Physiological Reports |
| spelling | doaj.art-52370cb3a48942ad92c9c1b5f1cdec7b2023-12-11T03:55:35ZengWileyPhysiological Reports2051-817X2023-08-011115n/an/a10.14814/phy2.15771Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto ratsAhmed A. Elmarakby0Karim M. Saad1G. Ryan Crislip2Jennifer C. Sullivan3Departments of Oral Biology & Diagnostic Sciences Augusta University Augusta Georgia USADepartments of Oral Biology & Diagnostic Sciences Augusta University Augusta Georgia USADepartments of Physiology Augusta University Augusta Georgia USADepartments of Physiology Augusta University Augusta Georgia USAAbstract Nitric oxide (NO) contributes to blood pressure (BP) regulation via its vasodilatory and anti‐inflammatory properties. We and others previously reported sex differences in BP in normotensive and hypertensive rat models where females have lower BP than age‐matched males. As females are known to have greater NO bioavailability than age‐matched males, the current study was designed to test the hypothesis that anesthetized female normotensive Wistar Kyoto rats (WKY) are more responsive to acute NOS inhibition‐induced increases in BP compared to male WKY. Twelve‐week‐old male and female WKY were randomized to infusion of the nonspecific NOS inhibitor NG‐nitro‐L‐arginine methyl ester (L‐NAME, 1 mg/kg/min) or selective NOS1 inhibition with vinyl‐L‐NIO (VNIO, 0.5 mg/kg/min) for 60 min. Mean arterial BP, glomerular filtration rate (GFR), urine volume, and electrolyte excretion were assessed before, and during L‐NAME or VNIO infusion. L‐NAME and VNIO significantly increased BP in both sexes; however, the increase in BP with L‐NAME infusion was greater in females versus males compared to baseline BP values. Acute infusion of neither L‐NAME nor VNIO for 60 min altered GFR in either sex. However, urine volume, sodium, chloride and potassium excretion levels increased comparably in male and female WKY with L‐NAME and VNIO infusion. Our findings suggest sex differences in BP responses to acute non‐isoform‐specific NOS inhibition in WKY, with females being more responsive to L‐NAME‐induced elevations in BP relative to male WKY. However, sex differences in the BP response did not coincide with sex differences in renal hemodynamic responses to acute NOS inhibition.https://doi.org/10.14814/phy2.15771blood pressureL‐NAMErenal hemodynamicssexVNIOWKY |
| spellingShingle | Ahmed A. Elmarakby Karim M. Saad G. Ryan Crislip Jennifer C. Sullivan Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats Physiological Reports blood pressure L‐NAME renal hemodynamics sex VNIO WKY |
| title | Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats |
| title_full | Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats |
| title_fullStr | Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats |
| title_full_unstemmed | Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats |
| title_short | Acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male Wistar Kyoto rats |
| title_sort | acute nitric oxide synthase inhibition induces greater increases in blood pressure in female versus male wistar kyoto rats |
| topic | blood pressure L‐NAME renal hemodynamics sex VNIO WKY |
| url | https://doi.org/10.14814/phy2.15771 |
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