{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T01:41:20Z","timestamp":1771378880568,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,19]],"date-time":"2023-04-19T00:00:00Z","timestamp":1681862400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Vicore Pharma AB"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Substantial evidence supports the involvement of the renin-angiotensin system in pulmonary hypertension (PH), and the angiotensin II type 2 receptor (AT2R) is known to exert tissue protective actions. The effect of the selective AT2R agonist C21 (also known as Compound 21 or buloxibutid) was evaluated in the rat Sugen-hypoxia PH model. After a single injection of Sugen 5416 and hypoxia for 21 days, C21 (2 or 20 mg\/kg) or vehicle was administered perorally twice daily from Day 21 to Day 55. On Day 56, hemodynamic assessments were performed, and lung and heart tissue were prepared for quantification of cardiac and vascular remodeling and fibrosis. Treatment with C21 20 mg\/kg improved cardiac output and stroke volume and decreased right ventricular hypertrophy (all p &lt; 0.05). Treatment with C21 2 mg\/kg significantly decreased vessel wall and muscular layer thickness and increased the luminal opening in vessels &gt;100 \u03bcm (all p &lt; 0.05). There were no significant differences between the two C21 doses on any parameter, and post hoc analyses comparing the merged C21 groups with the vehicle group showed that C21 treatment reduced vascular remodeling (reduced endothelial proliferation and thickening of the vascular wall) in vessels of all sizes; moreover, the diastolic pulmonary artery pressure and right ventricular pressure were reduced along with reduction of right ventricular hypertrophy. Sugen 5416 and hypoxia increased pulmonary collagen deposition, which was counteracted by C21 20 mg\/kg. In conclusion, the effects of C21 on vascular remodeling, hemodynamic alterations, and fibrosis suggest that AT2R agonists may have a role in Group 1 and 3 PH treatment.<\/jats:p>","DOI":"10.3390\/ijms24087478","type":"journal-article","created":{"date-parts":[[2023,4,19]],"date-time":"2023-04-19T03:20:39Z","timestamp":1681874439000},"page":"7478","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Effects of the Oral Angiotensin II Type 2 Receptor Agonist C21 in Sugen-Hypoxia Induced Pulmonary Hypertension in Rats"],"prefix":"10.3390","volume":"24","author":[{"given":"G\u00f6ran","family":"Tornling","sequence":"first","affiliation":[{"name":"Respiratory Medicine Division, Department of Medicine Solna, Karolinska Institutet, 17177 Stockholm, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rohit","family":"Batta","sequence":"additional","affiliation":[{"name":"Vicore Pharma AB, 11127 Stockholm, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4577-8110","authenticated-orcid":false,"given":"Dan","family":"Salvail","sequence":"additional","affiliation":[{"name":"IPS Therapeutique Inc., Sherbrooke, QC J1L 2T9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Johan","family":"Raud","sequence":"additional","affiliation":[{"name":"Vicore Pharma AB, 11127 Stockholm, Sweden"},{"name":"Institute of Environmental Medicine, Karolinska Institutet, 17177 Stockholm, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christopher P.","family":"Denton","sequence":"additional","affiliation":[{"name":"Centre for Rheumatology, Royal Free Hospital, University College Medical School, London NW3 2PS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"306","DOI":"10.1016\/S2213-2600(15)00543-3","article-title":"A global view of pulmonary hypertension","volume":"4","author":"Hoeper","year":"2016","journal-title":"Lancet Respir. 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